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Tubing for bimini or dodger
I am looking for any suggestions for a material that can be used to
fill the void in a PVC or ABS tubing, if and when used as tubing for a bimini or the like. What size would you recommend? Some thoughts include: epoxy, liquid foam, (cement -concrete???)..... Also what about using braided cable as a sort of rebar in the tubing before filling tubing void? Also what about using 3/4 or 1 inch copper tubing for a bimini or dodger (plumbing supplies) with same tech. as above. Thanks in advance. |
I am not sure you exactly grasp the forces that act on boats at sea. About
the only thing that would make ABS pipe strong enough to stand up as a Bimini frame would be a stainless tube on the outside. :-) Same is true for that copper tube support on your windvane. One good quartering wave and it will collapse against the transom. Most of the failures of commercial stering vanes are in the stainless support structure. 316 Stainless has a tensile strength of about 580 Mpa while hard drawn copper tube is under 200 Mpa. Heating to assemble it will soften it even further so soldered copper tube doesn't stand a chance. Same with the Bimini. The bending forces in tubing is all in the outer fiber. Nothing you put inside (other than a steel tube) that will help much. One good blow or an accidental steadying grab and it will be headed for the recycling yard. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com "Mic" wrote in message ... I am looking for any suggestions for a material that can be used to fill the void in a PVC or ABS tubing, if and when used as tubing for a bimini or the like. What size would you recommend? Some thoughts include: epoxy, liquid foam, (cement -concrete???)..... Also what about using braided cable as a sort of rebar in the tubing before filling tubing void? Also what about using 3/4 or 1 inch copper tubing for a bimini or dodger (plumbing supplies) with same tech. as above. Thanks in advance. |
If you're in fresh water (you can) use aluminum tubing, if you're in salt
use stainless steel. "Mic" wrote in message ... I am looking for any suggestions for a material that can be used to fill the void in a PVC or ABS tubing, if and when used as tubing for a bimini or the like. What size would you recommend? Some thoughts include: epoxy, liquid foam, (cement -concrete???)..... Also what about using braided cable as a sort of rebar in the tubing before filling tubing void? Also what about using 3/4 or 1 inch copper tubing for a bimini or dodger (plumbing supplies) with same tech. as above. Thanks in advance. |
Glenn Ashmore wrote:
I am not sure you exactly grasp the forces that act on boats at sea. About the only thing that would make ABS pipe strong enough to stand up as a Bimini frame would be a stainless tube on the outside. :-) Same is true for that copper tube support on your windvane. One good quartering wave and it will collapse against the transom. Most of the failures of commercial stering vanes are in the stainless support structure. 316 Stainless has a tensile strength of about 580 Mpa while hard drawn copper tube is under 200 Mpa. Heating to assemble it will soften it even further so soldered copper tube doesn't stand a chance. Same with the Bimini. The bending forces in tubing is all in the outer fiber. Nothing you put inside (other than a steel tube) that will help much. One good blow or an accidental steadying grab and it will be headed for the recycling yard. Idle curiosity acting here. Suppose...............you filled the PVC (or copper or whatever) with urethane foam. You know, the foam they sell for filling voids around windos at Lowes and Home Depot. I think that they now actually sell it in a couple of different formulations. Anyway, the stuff is a closed cell foam. I think it is pretty tough in compression and does not add much weight. Just wondering. |
On Sun, 12 Jun 2005 15:10:40 -0400, "Glenn Ashmore"
wrote: I am not sure you exactly grasp the forces that act on boats at sea. I am aware of "the forces that (can) act on boats at sea". I readily can not give you the ref. for the following, but am willing to accept them as reasonable: It was stated that about 93% of the time the winds are between 13-17 knots and for the remaining 7% of the time - 97% of that time they are between 17-21 knots. Its not the wind (for the most part) that does damage it the waves, as you suggest. I can not reasonably recall the force of a breaking wave on the deck of a boat but I do recall I was amazed at figure of that force. I do like the "cork" theory of a boat though... About the only thing that would make ABS pipe strong enough to stand up as a Bimini frame would be a stainless tube on the outside. :-) Same is true for that copper tube support on your windvane. The copper tube support that "Walt" designed is interesting, but when compared to the commercial vanes it is rather "light". I do believe he said it survived 20 knot situations. I have researched virtually all the sailing homebrew material available: - a PVC furling rig -homemade furling -homemade gennys, wind, water, fuel -wind vanes -polytarp sails -stitch and glue techniques -seahoods -bimini's and dodgers -PVC wisker poll - all sorts of ingenius ideas and techniques, I read once that someone called sailing a "thinking mans sport"... I define intelligents as someone who see's something other than what it is...ie a round disk is a dish, is a wheel, is a pully, is a gear....a rather simple example but thats the idea. Being smart I figure means that you dont have to work hard at learning things. Me I am a limited person....."stupidity is unlimited, genius is limited" :} One good quartering wave and it will collapse against the transom. Most of the failures of commercial stering vanes are in the stainless support structure. Personally I dont have any experience of the failure of wind vanes. But from the numerous crusing logs I have read most of the failures have been the vane "sail" and the associated rudder, as well as various fasteners. Failure of the support structure has been less common from my readings. YMMV. I have seen the origin designs of wind vanes, I think one version was of a friend of the Pardeys...actually earlier... Here is the URL link: http://www.freehandsteering.com/Windvane%20Story.htm http://www.freehandsteering.com/Image.htm http://www.geocities.com/Yosemite/Fo...ist/fhist.html "World War II hero and wind-vane self-steering innovator Blondie Hasler participated in a highly modified Folkboat named Jester. " "Jester incorporated many innovations. Blondie Hasler was a pioneer in the development of pendulum servo windvane self-steering gear. Jester was steered from below decks via a whipstaff. All sail handling could be performed from a central hatch without going on deck." Other links: http://www.freehandsteering.com/ http://www.hydrovane.com/ 316 Stainless has a tensile strength of about 580 Mpa while hard drawn copper tube is under 200 Mpa. Heating to assemble it will soften it even further so soldered copper tube doesn't stand a chance. Thanks for the specs...... Actually I think the weakest points in an ABS material would be where there are fittings like 90's etc. and the point at which the rig is fastened to the boat. (1 1/4" abs) This is just an "idea" with the thought of getting opinions. Yes, stainless tubing would be the way to go...$$$ and less workable as a homebrew project. I like the ideas of these sort of boat projects...not always the best answer but possibly a starting point. I am certain that by building your own boat you know what I mean. Same with the Bimini. The bending forces in tubing is all in the outer fiber. Nothing you put inside (other than a steel tube) that will help much. One good blow or an accidental steadying grab and it will be headed for the recycling yard. Humm...I am not so certain...but anything is possible although less probable.... Fairwinds and calm seas..... -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com "Mic" wrote in message ... I am looking for any suggestions for a material that can be used to fill the void in a PVC or ABS tubing, if and when used as tubing for a bimini or the like. What size would you recommend? Some thoughts include: epoxy, liquid foam, (cement -concrete???)..... Also what about using braided cable as a sort of rebar in the tubing before filling tubing void? Also what about using 3/4 or 1 inch copper tubing for a bimini or dodger (plumbing supplies) with same tech. as above. Thanks in advance. |
Mic wrote:
I am looking for any suggestions for a material that can be used to fill the void in a PVC or ABS tubing, if and when used as tubing for a bimini or the like. What size would you recommend? Some thoughts include: epoxy, liquid foam, (cement -concrete???)..... Also what about using braided cable as a sort of rebar in the tubing before filling tubing void? Also what about using 3/4 or 1 inch copper tubing for a bimini or dodger (plumbing supplies) with same tech. as above. Thanks in advance. Quoted from www.capehorn.com. Yves Gelinas is the designer of the CapeHorn self-steering system and this is the solution he came up with for the dodger frame for his Alberg30 that he circumnavigated with. "I wanted my dodger to whitstand a knockdown or a heavy sea falling aboard. The solution I came up with was to replace the stainless steel tubes of the frame with 2 inch dia. Dacron fire hose blown with air, much like a bicycle tire : hit by a sea, it collapses and pops up again. The ends of the tubes are capped with round PVC inserted into the tube and held with 3 hose clips at each end. I purchased screw-on tire valves, punched a hole near the end of the tube and screwed the valve in place. I need to blow it up only once a season, and after 20 years, it is still airtight." |
"Howard Peer" wrote Idle curiosity acting here. Suppose...............you filled the PVC (or copper or whatever) with urethane foam. You know, the foam they sell for filling voids around windos at Lowes and Home Depot. I think that they now actually sell it in a couple of different formulations. Anyway, the stuff is a closed cell foam. I think it is pretty tough in compression and does not add much weight. Just wondering. Not to get to far into the physics of materials but bending stress is the primary force acting on a Bimini frame. As a tube is put under stress the top will go under compression and the bottom tension. The sides and anything inside will be under varying amount of tension and compression that reduces to zero at the center or "neutral axis". The ability of a beam to resist bending is determined by the strength of the material, the shape and the distance of the furthest fiber to the "neutral Axis". The strength is expressed as the "Modulus of Elasticity" or how much a material will deform (strain) for a given amount of force (stress). The shape is expressed as the "Moment of Inertia" which is more or less the amount of material and its average distance from the neutral axis. (Greatly over simplified) Some examples of Modulus of elasticity a Stainless Steel 30,000,000 Hard copper 16,000,000 ABS 331,000 (about 1/100 of stainless) Examples of Moment of Inertia: 1/16" wall 1" tube .(stainless) .0203133 1/8" wall 1" tube (ABS) .0335558 Solid rod .0490874 Given that all are 1" in diameter the maximum distance to the neutral axis is the same .5" so an ABS pipe will be about 1/50 as stiff as a stainless tube. Notice that the Moment of a solid rod is only 45% greater than a 1/8" wall pipe. Filling a tube with a material with good compressive strength will prevent the tube from crimping but will do very little to keep it from bending. Also the corners must be considered. The large radius corners of a stainless frame spread the bending load over the whole arc while a typical ABS plumbing sweep Ell will concentrate the stress at the ends of the tube. This is especially bad for copper as the ends will be annealed from the heat of soldering. Considering the number of mangled Bimini frames you will find in any marine salage yard, an ABS frame would never survive even the slightest accidental knock. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
On Mon, 13 Jun 2005 08:34:20 -0400, "Glenn Ashmore"
wrote: "Howard Peer" wrote Idle curiosity acting here. Suppose...............you filled the PVC (or copper or whatever) with urethane foam. You know, the foam they sell for filling voids around windos at Lowes and Home Depot. I think that they now actually sell it in a couple of different formulations. Anyway, the stuff is a closed cell foam. I think it is pretty tough in compression and does not add much weight. Just wondering. Not to get to far into the physics of materials but bending stress is the primary force acting on a Bimini frame. As a tube is put under stress the top will go under compression and the bottom tension. The sides and anything inside will be under varying amount of tension and compression that reduces to zero at the center or "neutral axis". The ability of a beam to resist bending is determined by the strength of the material, the shape and the distance of the furthest fiber to the "neutral Axis". The strength is expressed as the "Modulus of Elasticity" or how much a material will deform (strain) for a given amount of force (stress). The shape is expressed as the "Moment of Inertia" which is more or less the amount of material and its average distance from the neutral axis. (Greatly over simplified) Some examples of Modulus of elasticity a Stainless Steel 30,000,000 Hard copper 16,000,000 ABS 331,000 (about 1/100 of stainless) Examples of Moment of Inertia: 1/16" wall 1" tube .(stainless) .0203133 1/8" wall 1" tube (ABS) .0335558 Solid rod .0490874 Given that all are 1" in diameter the maximum distance to the neutral axis is the same .5" so an ABS pipe will be about 1/50 as stiff as a stainless tube. Notice that the Moment of a solid rod is only 45% greater than a 1/8" wall pipe. Filling a tube with a material with good compressive strength will prevent the tube from crimping but will do very little to keep it from bending. Also the corners must be considered. The large radius corners of a stainless frame spread the bending load over the whole arc while a typical ABS plumbing sweep Ell will concentrate the stress at the ends of the tube. This is especially bad for copper as the ends will be annealed from the heat of soldering. Considering the number of mangled Bimini frames you will find in any marine salage yard, an ABS frame would never survive even the slightest accidental knock. -- Glenn Ashmore Glenn I checked out you boatbuilding page, and I do remember reading it a while ago, I liked it, it had personality. I have done some futher consideration. You know all the cloth dodgers I have seen, once they are setup they are never taken down (winter storage may be an exception), which I also know from my own experience. The cruising logs I have read many have opted for a "hard dodger" or commented that they might have prefered one. I have seen a few web pages about building one...and well they can look OK or not visually pleasing. Glenn are you planning on a hard dodger or a dog house on your construction or?????? I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
1088 wrote:
I saw something different at a fiberglass store. Kind of a composite of rolled up mat and resin that was sold in 8 foot pieces. It looks like dark red pvc pipe except solid. about 1inch diameter round rod. They tell me fiberglass is 5 times stronger than steel but who knows. The problem was they didn't sell any elbows or angles, so there wasn't any equally strong way to connect the runs together. I thought about pouring ortho resin with some mat scraps into a pvc pipe and making something that your life wouldn't have to depend on. Post what you find out, I think it's a great idea. On Sun, 12 Jun 2005 15:38:01 GMT, (Mic) wrote: I am looking for any suggestions for a material that can be used to fill the void in a PVC or ABS tubing, if and when used as tubing for a bimini or the like. What size would you recommend? Some thoughts include: epoxy, liquid foam, (cement -concrete???)..... Also what about using braided cable as a sort of rebar in the tubing before filling tubing void? Also what about using 3/4 or 1 inch copper tubing for a bimini or dodger (plumbing supplies) with same tech. as above. Thanks in advance. I used chimney rods to construct my "conestoga" style dodger frame. The wife sewed up the canopy, and a bug screen for the after end. a topper and side curtains are still in the clouds. I made end brackets out of 1/2" copper pipe squeezed in a vice. Cheap, flexible, indestructible. Still solid enought to grab when going foreward, flexible enough to avoid being crushed, should you be standing up going under a low bridge;-) Terry K |
Mic wrote:
On Sun, 12 Jun 2005 15:10:40 -0400, "Glenn Ashmore" wrote: I am not sure you exactly grasp the forces that act on boats at sea. I am aware of "the forces that (can) act on boats at sea". I readily can not give you the ref. for the following, but am willing to accept them as reasonable: It was stated that about 93% of the time the winds are between 13-17 knots and for the remaining 7% of the time - 97% of that time they are between 17-21 knots. Its not the wind (for the most part) that does damage it the waves, as you suggest. I can not reasonably recall the force of a breaking wave on the deck of a boat but I do recall I was amazed at figure of that force. I do like the "cork" theory of a boat though... Forget the wind and the waves. The problem with biminis and like structures is they're inevitably used as handholds, to support 200 LB people being tossed about in a seaway. This takes a toll even on the sturdy stainless steel ones. Matt O. |
Mic wrote:
I am aware of "the forces that (can) act on boats at sea". I readily can not give you the ref. for the following, but am willing to accept them as reasonable: It would seem that you aren't really aware ... It was stated that about 93% of the time the winds are between 13-17 knots and for the remaining 7% of the time - 97% of that time they are between 17-21 knots. It may have been "stated" but that doesn't make it true or meaningful. First of all, the "average" wind varies a fair amount by location and season, so any statistical claim such as that is just nonsense. In Boston, for example, these numbers hold for July, the calmest month. But in May and September there are numerous "average wind" observations over 25 knots. Boston is somewhat windier than most cities, but it is fairly representative of the New England coast. The trades can be even windier. And the "average wind" is meaningless when evaluating stresses on a dodger or other accessories; it is the gusts that are significant. Here the "93% point" in May and Sept is up around 23 knots, and 2% of the gusts are over 30 knots. In fact, if you just look at the record gusts, you'll find that most cities in the US have had high gusts (over 40 knots) in almost every month of the year. Thus, any permanently rigged dodger has to be able handle that. My standard is 50 knots - that is, when I leave the boat unattended, I assume that it can withstand gusts up to about 50 knots. Above that point, I might consider adding docklines or removing canvas. Designing something to "average winds" is silly. Its not the wind (for the most part) that does damage it the waves, as you suggest. Actually, for the case of a dodger, its probably your brother-in-law falling into it that you have to worry about. The frame should be at least strong enough to hold a person; ideally it should be able to withstand a person falling heavily against it. I can not reasonably recall the force of a breaking wave on the deck of a boat but I do recall I was amazed at figure of that force. If you are on the wrong side of a "plunging breaker" your dodger is the least of your worries ... .... The copper tube support that "Walt" designed is interesting, but when compared to the commercial vanes it is rather "light". I do believe he said it survived 20 knot situations. 20 knots? What's the point? Self steering should be bulletproof, not good enough for a daysail. I have researched virtually all the sailing homebrew material available: .... The common aspect of of most of the "home brew" techniques is that they have been proven worthless. For example, how many home built ferro-cement boats are still sailing? Home many blue poly sails do you see? There are a few notable exceptions, but most of the home brew building materials are junk. Why don't you see blue poly dodgers? Because most people understand that the materials are only about 20% of the value of the project. Most of the value is in the craft of assembly and finish. Why would anyone use third rate materials for something that takes a lot of manual labor? My oldest sailing friends have cruised aboard for many years on a low budget. Their current boat has probably tripled in value under their careful restoration. They've done all their own canvas (and much of mine), much of their rigging, replaced the engine and most mechanicals, added wind and solar power, many, many, coats of varnish. And one thing that stands out is that most of their work looks like it was done by a professional shipyard, or better. All of the materials are exactly what they should be, whether its stainless, teak, or Sunbrella. I think they did use pvc for one project - supports for solar panels that are only deployed at anchor - but I'm guessing that was just a prototype that will soon be replaced by stainless. |
If you want to avoid working with stainless tube a hard dodger or bimini
might be a good alternative. You can make the form with masonite over some shaped 2x6s. Just paint and wax the masonite and lay the glass over it. You would need to provide for additional thickness at the edges and possibly a ridge across the center to add some stiffness. As I get older a nice warm hard dodger extending back over the cockpit sounds more and more attractive but Rutu was not designed for that. We will have a split Bimini hung fore and aft of the traveler arch and possibly a soft dodger if the boat stays here on the Georgia so I can extend my sailing season. In the Leewards where we hope to be when we reach the "post-tuition" stage of life we will just use the Bimini. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com Glenn I checked out you boatbuilding page, and I do remember reading it a while ago, I liked it, it had personality. I have done some futher consideration. You know all the cloth dodgers I have seen, once they are setup they are never taken down (winter storage may be an exception), which I also know from my own experience. The cruising logs I have read many have opted for a "hard dodger" or commented that they might have prefered one. I have seen a few web pages about building one...and well they can look OK or not visually pleasing. Glenn are you planning on a hard dodger or a dog house on your construction or?????? I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
On Mon, 13 Jun 2005 14:43:30 -0400, Jeff wrote:
Mic wrote: I am aware of "the forces that (can) act on boats at sea". I readily can not give you the ref. for the following, but am willing to accept them as reasonable: It would seem that you aren't really aware ... It was stated that about 93% of the time the winds are between 13-17 knots and for the remaining 7% of the time - 97% of that time they are between 17-21 knots. It may have been "stated" but that doesn't make it true or meaningful. The above statement can be said about anthing. But If you take your own experience and that of others from their logs then come to your own conclusion on its relative truth or meaningfulness. First of all, the "average" wind varies a fair amount by location and season, so any statistical claim such as that is just nonsense. Yep. The reputation of the tasman sea is an example or the north atlantic. But the trade winds are different and the pacific "milk run"... In Boston, for example, these numbers hold for July, the calmest month. But in May and September there are numerous "average wind" observations over 25 knots. Boston is somewhat windier than most cities, but it is fairly representative of the New England coast. The trades can be even windier. And the "average wind" is meaningless when evaluating stresses on a dodger or other accessories; it is the gusts that are significant. Here the "93% point" in May and Sept is up around 23 knots, and 2% of the gusts are over 30 knots. Interesting link http://web.usna.navy.mil/~phmiller/usna1.html In fact, if you just look at the record gusts, you'll find that most cities in the US have had high gusts (over 40 knots) in almost every month of the year. Thus, any permanently rigged dodger has to be able handle that. Yep, although I have never seen a claim by any maker of tests to and of their dodgers., why? My standard is 50 knots - that is, when I leave the boat unattended, I assume that it can withstand gusts up to about 50 knots. Above that point, I might consider adding docklines or removing canvas. Designing something to "average winds" is silly. Yep, but designed to force 5 huricanes, it that practical or common. Its not the wind (for the most part) that does damage it the waves, as you suggest. Actually, for the case of a dodger, its probably your brother-in-law falling into it that you have to worry about. The frame should be at least strong enough to hold a person; ideally it should be able to withstand a person falling heavily against it. Probably, but I doubt any standard commercial dodger would survive a 200lbs person in all situations without damage. I can not reasonably recall the force of a breaking wave on the deck of a boat but I do recall I was amazed at figure of that force. If you are on the wrong side of a "plunging breaker" your dodger is the least of your worries ... Yep.... ... The copper tube support that "Walt" designed is interesting, but when compared to the commercial vanes it is rather "light". I do believe he said it survived 20 knot situations. 20 knots? What's the point? Self steering should be bulletproof, not good enough for a daysail. I doubt that any of the initial prototype designs qualify the ones used to cross oceans, and even some of the current ones in an all bulletproof design. How many boats have the ready provision for emerg. steering? I only know of one production boat as such. Why dont they have that, is almost common sense, (common sense isnt so common:{} ) Most are of a homebrew design. either as foresights or as required. I have researched virtually all the sailing homebrew material available: ... The common aspect of of most of the "home brew" techniques is that they have been proven worthless. For example, how many home built ferro-cement boats are still sailing? That is an exception example. I figure the best construction tech. is the one Glen Ashmore is using, and relative to quality control will be better than just about any production boat. Homebrew maybe worthless to some but an inspiration to others, like Hugh Piggots brake disc wind generator, etc, etc...... Stitch and glue is a homebrew tech. and is accepted as a commonly acceptable tech. etc. Home many blue poly sails do you see? Well, not many. But they are mostly on 18footer or less. Ususally the stitch and glue dingys.... but the knowledge and tech. could be applied in certain situations... an those that have used them would have spent more on sails than in the construction of their boat. There are a few notable exceptions, but most of the home brew building materials are junk. Why don't you see blue poly dodgers? Because most people understand that the materials are only about 20% of the value of the project. Most of the value is in the craft of assembly and finish. Why would anyone use third rate materials for something that takes a lot of manual labor? Yep. This can be applied to production boats. Refer to Bob Pascoe website. My oldest sailing friends have cruised aboard for many years on a low budget. Their current boat has probably tripled in value under their careful restoration. They've done all their own canvas (and much of mine), much of their rigging, replaced the engine and most mechanicals, added wind and solar power, many, many, coats of varnish. And one thing that stands out is that most of their work looks like it was done by a professional shipyard, or better. All of the materials are exactly what they should be, whether its stainless, teak, or Sunbrella. I think they did use pvc for one project - supports for solar panels that are only deployed at anchor - but I'm guessing that was just a prototype that will soon be replaced by stainless. I have heard and seen many boaters using PVC and blue poly tarps for their winter covers. Now the tarps may only last a season or two, but no one, that I know of has had an issue with the PVC supports other than the tech. they used to secure them to the boat. Some tent poles are made of fiberglass and it is amazing how much they bend, I haven seen or heard of one breaking but thats not to say they dont. Look at the condition on Everest, and the material that are used, sort of like a fixed sail on land. |
Mic wrote:
.... The cruising logs I have read many have opted for a "hard dodger" or commented that they might have prefered one. I have seen a few web pages about building one...and well they can look OK or not visually pleasing. My boat has a "hardtop" which is really a 'glass platform supported by heavy steel tubes. Its strong enough to walk on, large enough for three solar panels, and ridged enough for the main traveler. Its surrounded by canvas, with large windows and flys screens. The way our cockpit is laid out, this has become an extra room. With the full canvas surround, its possible to sail in freezing weather; when the Sun hits the windows, it becomes a greenhouse. The downside is that we tend to leave too much canvas up. Those who sail these boats down south often remove all of the canvas for full ventilation. Its construction is far beyond my capabilities, especially since windows and gutters are molded in, and carbon fibre is used to stiffen it. If I had to do something like this myself, I would have someone fabricate a strong frame in stainless, and then sew my own canvas around it. Here's a picture taken late in October, when the average gust in 18 knots: http://www.sv-loki.com/Along_the_Way/surround.jpg |
Mic wrote:
.... It was stated that about 93% of the time the winds are between 13-17 knots and for the remaining 7% of the time - 97% of that time they are between 17-21 knots. It may have been "stated" but that doesn't make it true or meaningful. The above statement can be said about anthing. But If you take your own experience and that of others from their logs then come to your own conclusion on its relative truth or meaningfulness. I think just about all of the readers here would think the the maximum gust strength in more significant than the average wind strength. In many locations, the average summer wind could be offered as proof that sailing is physically impossible! First of all, the "average" wind varies a fair amount by location and season, so any statistical claim such as that is just nonsense. Yep. The reputation of the tasman sea is an example or the north atlantic. But the trade winds are different and the pacific "milk run"... In all of those cases you'll encounter winds stronger than your implied average. .... Interesting link http://web.usna.navy.mil/~phmiller/usna1.html lots of neat stuff there ... anything in particular? In fact, if you just look at the record gusts, you'll find that most cities in the US have had high gusts (over 40 knots) in almost every month of the year. Thus, any permanently rigged dodger has to be able handle that. Yep, although I have never seen a claim by any maker of tests to and of their dodgers., why? Its a little hard - there are too many variables. And if no one does it, there's no reason for anyone to do it. Actually, I expect the various components of the dodger are warrantied for manufacturing flaws, such as stitching coming out, but there are very few products covered for hurricane damage. My standard is 50 knots - that is, when I leave the boat unattended, I assume that it can withstand gusts up to about 50 knots. Above that point, I might consider adding docklines or removing canvas. Designing something to "average winds" is silly. Yep, but designed to force 5 huricanes, it that practical or common. No, obviously at some point it is prudent to remove the canvas. However, you made comments that seemed to imply that wind over 21 knots is so uncommon as to be not worth considering. The one time my boat was in the the direct path of a hurricane (Bob, '91, but diminished to marginal hurricane strength) I stripped all sail and canvas. However, of the 350 boats on my marina, few stripped everything and there was only minor damage. Clearly, most of the dodgers were built to at least minimal hurricane strength. My cousin's boat was carried a mile inland and had to be lifted out by helicopter, but the dodger survived. Actually, for the case of a dodger, its probably your brother-in-law falling into it that you have to worry about. The frame should be at least strong enough to hold a person; ideally it should be able to withstand a person falling heavily against it. Probably, but I doubt any standard commercial dodger would survive a 200lbs person in all situations without damage. Many are built to hold the weight of a full sized person hanging from it as they go down the companionway. I doubt a pvc frame would hold that. Actually, this situation is probably the key issue of this discussion. .... How many boats have the ready provision for emerg. steering? I only know of one production boat as such. Why dont they have that, is almost common sense, (common sense isnt so common:{} ) Most are of a homebrew design. either as foresights or as required. My boat has two (potentially) independent rudder systems, with provision for an emergency tiller on either. My previous boat, and many quality boats with wheel steering, has provision for an emergency tiller. Beyond that, I'm not sure what the value of true emergency steering is, given that 99% of boats almost never leave SeaTow range. Would a Catalina 30 buyer pay a few thousand extra for this capability? Wind vane self steering is useful for long distance passage makers, and for them, a fully redundant backup rudder is handy, but this is an after market issue. Frankly, if I were building a boat specifically for long distance passages, I'd want to minimize the chance of damage, with a heavy duty rudder mounted on skeg. I have researched virtually all the sailing homebrew material available: ... The common aspect of of most of the "home brew" techniques is that they have been proven worthless. For example, how many home built ferro-cement boats are still sailing? That is an exception example. No, that's right up there with poly sails and pvc davits. And don't forget pepper in bottom paint. .... Stitch and glue is a homebrew tech. and is accepted as a commonly acceptable tech. etc. This is one exception I was thinking of. However, its only useful for small boats. Home many blue poly sails do you see? Well, not many. But they are mostly on 18footer or less. Ususally the stitch and glue dingys.... but the knowledge and tech. could be applied in certain situations... an those that have used them would have spent more on sails than in the construction of their boat. If your goal is to prove that that you can make a mediocre (at best) boat for pocket change, fine. And I'll even admit that the first boat I built had a sail made from an old bedsheet. However, sailcloth is about a buck a square foot. Spinnaker cloth is even less. So what do you save? 50 bucks? If I'm going to sit at the sewing machine for a few hours, plus put in a mess of grommets, I'd rather spend the $50 and have something I'm proud of. There are a few notable exceptions, but most of the home brew building materials are junk. Why don't you see blue poly dodgers? Because most people understand that the materials are only about 20% of the value of the project. Most of the value is in the craft of assembly and finish. Why would anyone use third rate materials for something that takes a lot of manual labor? Yep. This can be applied to production boats. Refer to Bob Pascoe website. Actually, I'd say that most of Pascoe's horrible examples are a big step up from poly dodgers. I will admit that I chartered an Irwin for a season (that was the Hurricane Bob boat) and it was such a POS that my subsequent two boats were from high quality manufacturers. .... I have heard and seen many boaters using PVC and blue poly tarps for their winter covers. Now the tarps may only last a season or two, but no one, that I know of has had an issue with the PVC supports other than the tech. they used to secure them to the boat. Some tent poles are made of fiberglass and it is amazing how much they bend, I haven seen or heard of one breaking but thats not to say they dont. Look at the condition on Everest, and the material that are used, sort of like a fixed sail on land. Well, of course a blue poly tarp is not a bad winter sail cover, I've even used them for a few seasons. But isn't that a case of using a material for it's actual designed purpose? Most shrink wrap frames around here are built from very cheap wood strapping. PVC, conduit, or almost anything else is a step up. |
On Mon, 13 Jun 2005 19:25:36 -0400, Jeff wrote:
Mic wrote: ... It was stated that about 93% of the time the winds are between 13-17 knots and for the remaining 7% of the time - 97% of that time they are between 17-21 knots. It may have been "stated" but that doesn't make it true or meaningful. The above statement can be said about anthing. But If you take your own experience and that of others from their logs then come to your own conclusion on its relative truth or meaningfulness. I think just about all of the readers here would think the the maximum gust strength in more significant than the average wind strength. yep..a gust is not sustained winds. In many locations, the average summer wind could be offered as proof that sailing is physically impossible! I really cant think of any, where would you suggest? First of all, the "average" wind varies a fair amount by location and season, so any statistical claim such as that is just nonsense. Yep. The reputation of the tasman sea is an example or the north atlantic. But the trade winds are different and the pacific "milk run"... In all of those cases you'll encounter winds stronger than your implied average. Yep thats why I mentioned them, and other than the "horn" and the tip of south africa, well the artics too...relative to the vastness of the ocean, I dont consider that alot. How many people do you see go out when it is 30 knots sustained. Near zero. ... Interesting link http://web.usna.navy.mil/~phmiller/usna1.html lots of neat stuff there ... anything in particular? Yes....Stiffness Reduction of Marine Composites http://web.usna.navy.mil/~phmiller/J...24fatigue.html In fact, if you just look at the record gusts, you'll find that most cities in the US have had high gusts (over 40 knots) in almost every month of the year. Thus, any permanently rigged dodger has to be able handle that. Yep, although I have never seen a claim by any maker of tests to and of their dodgers., why? Its a little hard - there are too many variables. And if no one does it, there's no reason for anyone to do it. Actually, I expect the various components of the dodger are warrantied for manufacturing flaws, such as stitching coming out, but there are very few products covered for hurricane damage. Right...so it all kind of relative and somewhat subjective. My standard is 50 knots - that is, when I leave the boat unattended, I assume that it can withstand gusts up to about 50 knots. Above that point, I might consider adding docklines or removing canvas. Designing something to "average winds" is silly. Yep, but designed to force 5 huricanes, it that practical or common. No, obviously at some point it is prudent to remove the canvas. However, you made comments that seemed to imply that wind over 21 knots is so uncommon as to be not worth considering. No actually that is what is the most worth considering, but am of the opinion that it is not a frequent stat., "sustained" winds over 21 knots, geographic exceptions noted. The one time my boat was in the the direct path of a hurricane (Bob, '91, but diminished to marginal hurricane strength) I stripped all sail and canvas. However, of the 350 boats on my marina, few stripped everything and there was only minor damage. Clearly, most of the dodgers were built to at least minimal hurricane strength. My cousin's boat was carried a mile inland and had to be lifted out by helicopter, but the dodger survived. Actually, for the case of a dodger, its probably your brother-in-law falling into it that you have to worry about. The frame should be at least strong enough to hold a person; ideally it should be able to withstand a person falling heavily against it. Probably, but I doubt any standard commercial dodger would survive a 200lbs person in all situations without damage. Many are built to hold the weight of a full sized person hanging from it as they go down the companionway. I doubt a pvc frame would hold that. Actually, this situation is probably the key issue of this discussion. Actually I prefer ABS...If I have the time and material handy,,,I might like to do some tests.. ... How many boats have the ready provision for emerg. steering? I only know of one production boat as such. Why dont they have that, is almost common sense, (common sense isnt so common:{} ) Most are of a homebrew design. either as foresights or as required. My boat has two (potentially) independent rudder systems, with provision for an emergency tiller on either. My previous boat, and many quality boats with wheel steering, has provision for an emergency tiller. Yes, but not rudder.... I have seen a "homebrew" pindel and grudeon rudder that worked like a cassette. The cassette was inserted to the grudeons and then the rudder through the cassette - very cool.....so easy and cheap to make. By using this cassette method is ingenious,,,,as trying to install a rudder in full on rough conditions might be more of a challenge. Beyond that, I'm not sure what the value of true emergency steering is, given that 99% of boats almost never leave SeaTow range. Would a Catalina 30 buyer pay a few thousand extra for this capability? Wind vane self steering is useful for long distance passage makers, and for them, a fully redundant backup rudder is handy, but this is an after market issue. Frankly, if I were building a boat specifically for long distance passages, I'd want to minimize the chance of damage, with a heavy duty rudder mounted on skeg. Would that be "balanced"? If so How? Well thats really another topic "rudders and keels". I see a lot of spade rudders out there....at least the boats I am noticing. I have researched virtually all the sailing homebrew material available: ... The common aspect of of most of the "home brew" techniques is that they have been proven worthless. For example, how many home built ferro-cement boats are still sailing? That is an exception example. No, that's right up there with poly sails and pvc davits. And don't forget pepper in bottom paint. Havent seen the pvc davits anywhere.....yet;}} ... Stitch and glue is a homebrew tech. and is accepted as a commonly acceptable tech. etc. This is one exception I was thinking of. However, its only useful for small boats. Home many blue poly sails do you see? Well, not many. But they are mostly on 18footer or less. Ususally the stitch and glue dingys.... but the knowledge and tech. could be applied in certain situations... an those that have used them would have spent more on sails than in the construction of their boat. If your goal is to prove that that you can make a mediocre (at best) boat for pocket change, fine. And I'll even admit that the first boat I built had a sail made from an old bedsheet. However, sailcloth is about a buck a square foot. Spinnaker cloth is even less. So what do you save? 50 bucks? If I'm going to sit at the sewing machine for a few hours, plus put in a mess of grommets, I'd rather spend the $50 and have something I'm proud of. Actually I dont think many of the polys are sewn,,,,and your going to like the fact that some use carpet tape. There are a few notable exceptions, but most of the home brew building materials are junk. Why don't you see blue poly dodgers? Because most people understand that the materials are only about 20% of the value of the project. Most of the value is in the craft of assembly and finish. Why would anyone use third rate materials for something that takes a lot of manual labor? Yep. This can be applied to production boats. Refer to Bob Pascoe website. Actually, I'd say that most of Pascoe's horrible examples are a big step up from poly dodgers. I would not use poly on a dodger...never said I would. The point I was making was regarding you statement "Why would anyone use third rate materials for something that takes a lot of manual labor?" Was the fact of the state of build of many production boats apply to your comment and can not just be directed at homebrew projects. I will admit that I chartered an Irwin for a season (that was the Hurricane Bob boat) and it was such a POS that my subsequent two boats were from high quality manufacturers. ... I have heard and seen many boaters using PVC and blue poly tarps for their winter covers. Now the tarps may only last a season or two, but no one, that I know of has had an issue with the PVC supports other than the tech. they used to secure them to the boat. Some tent poles are made of fiberglass and it is amazing how much they bend, I haven seen or heard of one breaking but thats not to say they dont. Look at the condition on Everest, and the material that are used, sort of like a fixed sail on land. Well, of course a blue poly tarp is not a bad winter sail cover, I've even used them for a few seasons. But isn't that a case of using a material for it's actual designed purpose? Most shrink wrap frames around here are built from very cheap wood strapping. PVC, conduit, or almost anything else is a step up. |
Mic wrote:
In many locations, the average summer wind could be offered as proof that sailing is physically impossible! I really cant think of any, where would you suggest? The average wind in Myrtle Beach in August is 4 knots. Yep. The reputation of the tasman sea is an example or the north atlantic. But the trade winds are different and the pacific "milk run"... In all of those cases you'll encounter winds stronger than your implied average. Yep thats why I mentioned them, and other than the "horn" and the tip of south africa, well the artics too...relative to the vastness of the ocean, I dont consider that alot. But do you actually have a point to this? How many people do you see go out when it is 30 knots sustained. Near zero. This is total nonsense. While I don't often leave the dock in high winds, at least once a year I find myself out in strong winds. Last year's episode had lighter wind than our normal max - it was about 30 but on the stern - it was the 10+ foot confused sea that annoyed my wife. And for a dodger, it isn't the wind while sailing that counts, the wind at the dock can be just as bad. A few days after I launched this year we had gusts to about 50. .... No, obviously at some point it is prudent to remove the canvas. However, you made comments that seemed to imply that wind over 21 knots is so uncommon as to be not worth considering. No actually that is what is the most worth considering, but am of the opinion that it is not a frequent stat., "sustained" winds over 21 knots, geographic exceptions noted. I have no idea what you're trying to say ... .... How many boats have the ready provision for emerg. steering? I only know of one production boat as such. Why dont they have that, is almost common sense, (common sense isnt so common:{} ) Most are of a homebrew design. either as foresights or as required. My boat has two (potentially) independent rudder systems, with provision for an emergency tiller on either. My previous boat, and many quality boats with wheel steering, has provision for an emergency tiller. Yes, but not rudder.... As I said, my current boat has two complete systems, including two rudders. I have seen a "homebrew" pindel and grudeon rudder that worked like a cassette. The cassette was inserted to the grudeons and then the rudder through the cassette - very cool.....so easy and cheap to make. By using this cassette method is ingenious,,,,as trying to install a rudder in full on rough conditions might be more of a challenge. Don't a number of dinghies use this arrangement? Frankly, if I were building a boat specifically for long distance passages, I'd want to minimize the chance of damage, with a heavy duty rudder mounted on skeg. Would that be "balanced"? If so How? Nope, it wouldn't be balanced. That's a nice attribute, but not necessary. If you're considering scenarios where you need to replace the rudder underway, you probably need a protected rudder more than a balanced one. Well thats really another topic "rudders and keels". I see a lot of spade rudders out there....at least the boats I am noticing. But its leads you to worrying about emergency rudders. This is not the path of simplicity. No, that's right up there with poly sails and pvc davits. And don't forget pepper in bottom paint. Havent seen the pvc davits anywhere.....yet;}} Fortunately, they haven't caught on, but I've seen a few. .... However, sailcloth is about a buck a square foot. Spinnaker cloth is even less. So what do you save? 50 bucks? If I'm going to sit at the sewing machine for a few hours, plus put in a mess of grommets, I'd rather spend the $50 and have something I'm proud of. Actually I dont think many of the polys are sewn,,,,and your going to like the fact that some use carpet tape. A real class act. But I understand. I've owned an old VW bug that was built out of parts salvaged from several bugs, a Karmann Ghia and an old Porsche. I've also owned a new Mercedes. Both had their charm, but believe me, the Mercedes was a lot more enjoyable to drive, especially if I had to drive more than walking distance from my apartment. Actually, I'd say that most of Pascoe's horrible examples are a big step up from poly dodgers. I would not use poly on a dodger...never said I would. The point I was making was regarding you statement "Why would anyone use third rate materials for something that takes a lot of manual labor?" Was the fact of the state of build of many production boats apply to your comment and can not just be directed at homebrew projects. OK. Are you claiming to because some builders use crap you're entitled to do the same? As you wish. |
On Mon, 13 Jun 2005 22:45:12 -0400, Jeff wrote:
Mic wrote: In many locations, the average summer wind could be offered as proof that sailing is physically impossible! I really cant think of any, where would you suggest? The average wind in Myrtle Beach in August is 4 knots. Yep. The reputation of the tasman sea is an example or the north atlantic. But the trade winds are different and the pacific "milk run"... In all of those cases you'll encounter winds stronger than your implied average. Yep thats why I mentioned them, and other than the "horn" and the tip of south africa, well the artics too...relative to the vastness of the ocean, I dont consider that alot. But do you actually have a point to this? yes the generalization of average winds as noted would not necessary apply to these regions. How many people do you see go out when it is 30 knots sustained. Near zero. This is total nonsense. While I don't often leave the dock in high winds, at least once a year I find myself out in strong winds. Last year's episode had lighter wind than our normal max - it was about 30 but on the stern - it was the 10+ foot confused sea that annoyed my wife. There is a big difference in being out when 30 knots of wind occur and going out when there is that much wind, it not nonsense...it is fact. As you said yourself you dont often go out in such conditions. And many in pleasure boating and even passage making dont either. And for a dodger, it isn't the wind while sailing that counts, the wind at the dock can be just as bad. yep A few days after I launched this year we had gusts to about 50. ... No, obviously at some point it is prudent to remove the canvas. However, you made comments that seemed to imply that wind over 21 knots is so uncommon as to be not worth considering. No actually that is what is the most worth considering, but am of the opinion that it is not a frequent stat., "sustained" winds over 21 knots, geographic exceptions noted. I have no idea what you're trying to say ... Simple I take the "statement" as reasonable fact based on experience and practically every cruiser log published on the net. That the average sustained winds are usually less than about 21 knots, certain geographically noted exceptions excluded. ... How many boats have the ready provision for emerg. steering? I only know of one production boat as such. Why dont they have that, is almost common sense, (common sense isnt so common:{} ) Most are of a homebrew design. either as foresights or as required. My boat has two (potentially) independent rudder systems, with provision for an emergency tiller on either. My previous boat, and many quality boats with wheel steering, has provision for an emergency tiller. Yes, but not rudder.... As I said, my current boat has two complete systems, including two rudders. How are they configured? Are they production original, is one a homebrew or off the shelf? I have seen a "homebrew" pindel and grudeon rudder that worked like a cassette. The cassette was inserted to the grudeons and then the rudder through the cassette - very cool.....so easy and cheap to make. By using this cassette method is ingenious,,,,as trying to install a rudder in full on rough conditions might be more of a challenge. Don't a number of dinghies use this arrangement? Maybe but not what I have seen? This arrangement was not on a dingy. Frankly, if I were building a boat specifically for long distance passages, I'd want to minimize the chance of damage, with a heavy duty rudder mounted on skeg. Would that be "balanced"? If so How? Nope, it wouldn't be balanced. That's a nice attribute, but not necessary. If you're considering scenarios where you need to replace the rudder underway, you probably need a protected rudder more than a balanced one. I really need to create another topic on the issue of rudder and keels. As I am looking at 2 significantly (keel and rudder) different boats. A grampian 26 and a bayfield 25 and will be looking for opinions from which to help make a decision. Well thats really another topic "rudders and keels". I see a lot of spade rudders out there....at least the boats I am noticing. But its leads you to worrying about emergency rudders. This is not the path of simplicity. Not necessarly. Alot of factors of necessary force on a tiller has to do with sail balance and rudder design, current,wind, etc/ No, that's right up there with poly sails and pvc davits. And don't forget pepper in bottom paint. Havent seen the pvc davits anywhere.....yet;}} Fortunately, they haven't caught on, but I've seen a few. ... However, sailcloth is about a buck a square foot. Spinnaker cloth is even less. So what do you save? 50 bucks? If I'm going to sit at the sewing machine for a few hours, plus put in a mess of grommets, I'd rather spend the $50 and have something I'm proud of. Actually I dont think many of the polys are sewn,,,,and your going to like the fact that some use carpet tape. A real class act. But I understand. I've owned an old VW bug that was built out of parts salvaged from several bugs, a Karmann Ghia and an old Porsche. I've also owned a new Mercedes. Both had their charm, but believe me, the Mercedes was a lot more enjoyable to drive, especially if I had to drive more than walking distance from my apartment. Actually, I'd say that most of Pascoe's horrible examples are a big step up from poly dodgers. I would not use poly on a dodger...never said I would. The point I was making was regarding you statement "Why would anyone use third rate materials for something that takes a lot of manual labor?" Was the fact of the state of build of many production boats apply to your comment and can not just be directed at homebrew projects. OK. Are you claiming to because some builders use crap you're entitled to do the same? As you wish. No. The thread was put out for opinions, a good thing. Come to think of it no one suggested any possible tests of methods or materials, I think should one proceed with such material, tests would be inorder. Design could be the determining factor in reasonable success or failure. As Glenn pointed out the strenght of a curve would be greater than a square....- not possible with abs. |
Mic wrote:
But do you actually have a point to this? yes the generalization of average winds as noted would not necessary apply to these regions. My point was the the generalization of average winds applies to very little when considering how strong something has to be. How many people do you see go out when it is 30 knots sustained. Near zero. This is total nonsense. While I don't often leave the dock in high winds, at least once a year I find myself out in strong winds. Last year's episode had lighter wind than our normal max - it was about 30 but on the stern - it was the 10+ foot confused sea that annoyed my wife. There is a big difference in being out when 30 knots of wind occur and going out when there is that much wind, it not nonsense...it is fact. As you said yourself you dont often go out in such conditions. And many in pleasure boating and even passage making dont either. There is a difference in the intent, but 30 knots is 30 knots regardless of the intent. This is a discussion about design, not intent. While daysailors have the option of never leaving the dock unless the short term forecast is perfect, passage makers have made an commitment to take whatever the sea offers. Boats must be designed to the most severe weather they might reasonably encounter. For this consideration, the "average wind" is meaningless. So what would you think is a reasonable design point? In all of the larger boats I've owned, I've been out in 40+ knots, anchored in 50+, and had 60+ at the dock. All of them have made Atlantic crossings (not by me!), including the 25 footer. There is, of course, a flip side to this. I have friends who bought heavy weather boats for the security they offer, then found its not worth raising sail until its blowing 20; others have light air boats that need to be reefed above 15. But this is a somewhat different design issue. .... Simple I take the "statement" as reasonable fact based on experience and practically every cruiser log published on the net. That the average sustained winds are usually less than about 21 knots, certain geographically noted exceptions excluded. Yes, this is true. Just not relevant to the discussion. As I said, my current boat has two complete systems, including two rudders. How are they configured? Are they production original, is one a homebrew or off the shelf? Off the shelf, standard configuration, 100 built, plus another 100 of related designs. On most boats of my design, the rudder is a balanced spade, and I've know of one case where one of the rudders got jammed and had to be disconnected. My boat, and about a third of the newer sisterships, has a skeg hung rudder. Handling under sail suffers a bit, though I'm not sure its really a downside, since I don't use it for "round the buoys" racing. BTW, many of the other boats I considered had similar setups. The sailboat next to me in the yard had twin rudders, and one of the other sailboats on my dock, of a completely different style, also has twin rudders. .... I see a lot of spade rudders out there....at least the boats I am noticing. But its leads you to worrying about emergency rudders. This is not the path of simplicity. Not necessarly. Alot of factors of necessary force on a tiller has to do with sail balance and rudder design, current,wind, etc/ Yes, you have to look at the whole package. My previous boat had a rig that was prone to being unbalanced and overpowering, so I was glad to have a balanced spade. Before that, I had a full keel that tracked "on rails" so the spade wasn't needed. |
On Tue, 14 Jun 2005 08:45:32 -0400, Jeff wrote:
Mic wrote: But do you actually have a point to this? yes the generalization of average winds as noted would not necessary apply to these regions. My point was the the generalization of average winds applies to very little when considering how strong something has to be. Good point, but to then figure that it has to be bullit proof is it reasonable for it to be built to withstand what max force? Where do you draw the line? That is my point. How many people do you see go out when it is 30 knots sustained. Near zero. This is total nonsense. While I don't often leave the dock in high winds, at least once a year I find myself out in strong winds. Last year's episode had lighter wind than our normal max - it was about 30 but on the stern - it was the 10+ foot confused sea that annoyed my wife. There is a big difference in being out when 30 knots of wind occur and going out when there is that much wind, it not nonsense...it is fact. As you said yourself you dont often go out in such conditions. And many in pleasure boating and even passage making dont either. There is a difference in the intent, but 30 knots is 30 knots regardless of the intent. This is a discussion about design, not intent. While daysailors have the option of never leaving the dock unless the short term forecast is perfect, passage makers have made an commitment to take whatever the sea offers. Yes if they are already out in it, but in the logs of Bumfuzzle on there way from panama to galapagoes in about 30 knots they were beating to the weather and wave, they made the decision to turn and run with the waves for the nearest port in SA. http://www.bumfuzzle.com/LogsDates.htm Also if you read bill_dietrich logs at: http://www.geocities.com/bill_dietri...agnoliaLog.txt Currently in Bahamas, you will see how many boats leave an anchorage and them shortly return... Bill has an excellent site at http://www.geocities.com/bill_dietri...boat.html#plan It is mostly a collection of thought of a huge amount of sailors collected over years from various sources.... Boats must be designed to the most severe weather they might reasonably encounter. For this consideration, the "average wind" is meaningless. Right average wind is meaningless, its the forces of the sea, as was pointed out in Glenn post. If most of the time the weather is not greater than 21 knots what do you reasonable design for? Do you design for the 7% of the time at the winds are above 21 knots? To design anthing nautical for just 21 knots would be foolish, I never suggested that, but rather reiterated a stat. I believe to be reasonable true. So what would you think is a reasonable design point? In all of the larger boats I've owned, I've been out in 40+ knots, anchored in 50+, and had 60+ at the dock. All of them have made Atlantic crossings (not by me!), including the 25 footer. I dont think I could answer that question, although in many instances builder and designers have lowered that point, when compared with earlier GRP production boats, but a much debatable subject. Some boats are designed with specific usage. But some near coastal craft have been taken on circumnavigations -blue water. There is, of course, a flip side to this. I have friends who bought heavy weather boats for the security they offer, then found its not worth raising sail until its blowing 20; others have light air boats that need to be reefed above 15. But this is a somewhat different design issue. Yep, that is somewhat of the issue I have in deciding between 2 boats. ... Simple I take the "statement" as reasonable fact based on experience and practically every cruiser log published on the net. That the average sustained winds are usually less than about 21 knots, certain geographically noted exceptions excluded. Yes, this is true. Just not relevant to the discussion. ????But this discussion always seems to focus around this issue. As I said, my current boat has two complete systems, including two rudders. How are they configured? Are they production original, is one a homebrew or off the shelf? Off the shelf, standard configuration, 100 built, plus another 100 of related designs. On most boats of my design, the rudder is a balanced spade, and I've know of one case where one of the rudders got jammed and had to be disconnected. My boat, and about a third of the newer sisterships, has a skeg hung rudder. Handling under sail suffers a bit, though I'm not sure its really a downside, since I don't use it for "round the buoys" racing. Are you a boat designer? BTW, many of the other boats I considered had similar setups. The sailboat next to me in the yard had twin rudders, and one of the other sailboats on my dock, of a completely different style, also has twin rudders. How are the twin rudders configured? What make of boat? I have seen a mono with a spade rudder and a transom hung one as well but this was an after design and more based on a emerg. 2nd rudder. ... I see a lot of spade rudders out there....at least the boats I am noticing. But its leads you to worrying about emergency rudders. This is not the path of simplicity. Not necessarly. Alot of factors of necessary force on a tiller has to do with sail balance and rudder design, current,wind, etc/ Yes, you have to look at the whole package. My previous boat had a rig that was prone to being unbalanced and overpowering, so I was glad to have a balanced spade. Before that, I had a full keel that tracked "on rails" so the spade wasn't needed. |
Mic wrote:
Good point, but to then figure that it has to be bullit proof is it reasonable for it to be built to withstand what max force? Where do you draw the line? That is my point. Somewhere above the average wind and below a Force 5 hurricane. There is a difference in the intent, but 30 knots is 30 knots regardless of the intent. This is a discussion about design, not intent. While daysailors have the option of never leaving the dock unless the short term forecast is perfect, passage makers have made an commitment to take whatever the sea offers. Yes if they are already out in it, but in the logs of Bumfuzzle on there way from panama to galapagoes in about 30 knots they were beating to the weather and wave, they made the decision to turn and run with the waves for the nearest port in SA. http://www.bumfuzzle.com/LogsDates.htm True, but they were still out in it. It just happened that in this case, they had an alternative. If they didn't have the alternative, would they have abandoned ship? Also if you read bill_dietrich logs at: http://www.geocities.com/bill_dietri...agnoliaLog.txt Currently in Bahamas, you will see how many boats leave an anchorage and them shortly return... Seen it all the time, been there myself. It doesn't change a thing. You must assume that every now and them you'll be caught in stronger winds than you normally are comfortable in. Frankly, these people are lucky that the weak link is their own nerve (or their stomachs), rather than the boat. I've never been happy on a boat that I don't have a lot of faith in - I like to think that the boat and its gear can handle any situation I'm willing to get into. .... So what would you think is a reasonable design point? In all of the larger boats I've owned, I've been out in 40+ knots, anchored in 50+, and had 60+ at the dock. All of them have made Atlantic crossings (not by me!), including the 25 footer. I dont think I could answer that question, although in many instances builder and designers have lowered that point, when compared with earlier GRP production boats, but a much debatable subject. If you plan to go out there, you had better be able to answer it. Every choice you make for gear and planning will have this in the background. One of the biggest mistakes people make is not understanding how they will really use their boat, especially cruising sailboats. It seems that some buyers equate the number of berths with blue water capability, or stainless fittings with quality construction. Other buyers are obsessed with getting the strongest, heaviest boat possible when they never leave their protected bay. It seems like every few weeks someone here asks advice on the proper boat for ocean passages, because they plan to learn to sail next year and want the right boat. Some boats are designed with specific usage. But some near coastal craft have been taken on circumnavigations -blue water. Absolutely true. However, when you hear of a boat foundering in a 40 knot gale offshore, you usually find its a lightweight coastal cruiser, or a poorly maintained older boat. And remember - you've been "surprised" that more boats don't have provisions for emergency rudders. Most of these coastal boats don't, in fact relatively few passage makers nowadays have that. There is, of course, a flip side to this. I have friends who bought heavy weather boats for the security they offer, then found its not worth raising sail until its blowing 20; others have light air boats that need to be reefed above 15. But this is a somewhat different design issue. Yep, that is somewhat of the issue I have in deciding between 2 boats. The couple that used a Westsail for an ICW trip found that using a tiller on such a heavy boat was just too much of a pain. They gave it up soon after returning. ... Simple I take the "statement" as reasonable fact based on experience and practically every cruiser log published on the net. That the average sustained winds are usually less than about 21 knots, certain geographically noted exceptions excluded. Yes, this is true. Just not relevant to the discussion. ????But this discussion always seems to focus around this issue. I can say no more. How are they configured? Are they production original, is one a homebrew or off the shelf? Off the shelf, standard configuration, 100 built, plus another 100 of related designs. On most boats of my design, the rudder is a balanced spade, and I've know of one case where one of the rudders got jammed and had to be disconnected. My boat, and about a third of the newer sisterships, has a skeg hung rudder. Handling under sail suffers a bit, though I'm not sure its really a downside, since I don't use it for "round the buoys" racing. Are you a boat designer? Nope, although that was my first major in school. I found my talents lie elsewhe I spent the last 25 years as a computer programmer. BTW, many of the other boats I considered had similar setups. The sailboat next to me in the yard had twin rudders, and one of the other sailboats on my dock, of a completely different style, also has twin rudders. How are the twin rudders configured? What make of boat? I have seen a mono with a spade rudder and a transom hung one as well but this was an after design and more based on a emerg. 2nd rudder. I suppose I have to tell eventually ... I have a catamaran, a PDQ 36. One rudder on each hull, off course, tied together with a crosslink attached to each quadrant. One is driven by a cable from the wheel; each can accept a tiller from above. Although space, speed, and stability were the primary factors in going with a cat, the safety of twin rudders, twin engines, and the flotation of twin hulls were a significant part of the decision. Jeff www.sv-loki.com |
On Tue, 14 Jun 2005 16:19:56 -0400, Jeff wrote:
Mic wrote: Good point, but to then figure that it has to be bullit proof is it reasonable for it to be built to withstand what max force? Where do you draw the line? That is my point. Somewhere above the average wind and below a Force 5 hurricane. Yep sounds "exactly right"...:}} There is a difference in the intent, but 30 knots is 30 knots regardless of the intent. This is a discussion about design, not intent. While daysailors have the option of never leaving the dock unless the short term forecast is perfect, passage makers have made an commitment to take whatever the sea offers. Yes if they are already out in it, but in the logs of Bumfuzzle on there way from panama to galapagoes in about 30 knots they were beating to the weather and wave, they made the decision to turn and run with the waves for the nearest port in SA. http://www.bumfuzzle.com/LogsDates.htm True, but they were still out in it. It just happened that in this case, they had an alternative. If they didn't have the alternative, would they have abandoned ship? I dont know, what do you think? But if they knew what the weather was would they have changed the time they left? Also if you read bill_dietrich logs at: http://www.geocities.com/bill_dietri...agnoliaLog.txt Currently in Bahamas, you will see how many boats leave an anchorage and them shortly return... Seen it all the time, been there myself. It doesn't change a thing. You must assume that every now and them you'll be caught in stronger winds than you normally are comfortable in. Frankly, these people are lucky that the weak link is their own nerve (or their stomachs), rather than the boat. Well if you read their logs particularly the ones in New Zealand and the issues with the SA builder of their Wild Cat, be very thankful you have a PDQ. I doubt it has to do with there nerve, rather the fact that they had issues beating to the weather and were making poor distance over ground. I've never been happy on a boat that I don't have a lot of faith in - I like to think that the boat and its gear can handle any situation I'm willing to get into. ... So what would you think is a reasonable design point? In all of the larger boats I've owned, I've been out in 40+ knots, anchored in 50+, and had 60+ at the dock. All of them have made Atlantic crossings (not by me!), including the 25 footer. I dont think I could answer that question, although in many instances builder and designers have lowered that point, when compared with earlier GRP production boats, but a much debatable subject. If you plan to go out there, you had better be able to answer it. Every choice you make for gear and planning will have this in the background. Really? I know exactly what mods I feel would be necessary and satisfied with. I dont believe anyone really knows what the necessary design point is, like you said " somewhere between average winds and Force 5 hurricane" hummm...wouldnt that be about 100 mph spread? It has been said so many times that in such situations it becomes more of an issue of sailing ability (decisions) than necessarily the boat. One of the biggest mistakes people make is not understanding how they will really use their boat, especially cruising sailboats. It seems that some buyers equate the number of berths with blue water capability, or stainless fittings with quality construction. Other buyers are obsessed with getting the strongest, heaviest boat possible when they never leave their protected bay. It seems like every few weeks someone here asks advice on the proper boat for ocean passages, because they plan to learn to sail next year and want the right boat. Some boats are designed with specific usage. But some near coastal craft have been taken on circumnavigations -blue water. Absolutely true. However, when you hear of a boat foundering in a 40 knot gale offshore, you usually find its a lightweight coastal cruiser, or a poorly maintained older boat. And remember - you've been "surprised" that more boats don't have provisions for emergency rudders. Most of these coastal boats don't, in fact relatively few passage makers nowadays have that. Any passage maker who hasnt considered or mad provision for an emerg rudder.....good luck to them they will need it. There is, of course, a flip side to this. I have friends who bought heavy weather boats for the security they offer, then found its not worth raising sail until its blowing 20; others have light air boats that need to be reefed above 15. But this is a somewhat different design issue. Yep, that is somewhat of the issue I have in deciding between 2 boats. The couple that used a Westsail for an ICW trip found that using a tiller on such a heavy boat was just too much of a pain. They gave it up soon after returning. ... Simple I take the "statement" as reasonable fact based on experience and practically every cruiser log published on the net. That the average sustained winds are usually less than about 21 knots, certain geographically noted exceptions excluded. Yes, this is true. Just not relevant to the discussion. ????But this discussion always seems to focus around this issue. I can say no more. How are they configured? Are they production original, is one a homebrew or off the shelf? Off the shelf, standard configuration, 100 built, plus another 100 of related designs. On most boats of my design, the rudder is a balanced spade, and I've know of one case where one of the rudders got jammed and had to be disconnected. My boat, and about a third of the newer sisterships, has a skeg hung rudder. Handling under sail suffers a bit, though I'm not sure its really a downside, since I don't use it for "round the buoys" racing. Are you a boat designer? Nope, although that was my first major in school. I found my talents lie elsewhe I spent the last 25 years as a computer programmer. BTW, many of the other boats I considered had similar setups. The sailboat next to me in the yard had twin rudders, and one of the other sailboats on my dock, of a completely different style, also has twin rudders. How are the twin rudders configured? What make of boat? I have seen a mono with a spade rudder and a transom hung one as well but this was an after design and more based on a emerg. 2nd rudder. I suppose I have to tell eventually ... I have a catamaran, a PDQ 36. One rudder on each hull, off course, tied together with a crosslink attached to each quadrant. One is driven by a cable from the wheel; each can accept a tiller from above. Although space, speed, and stability were the primary factors in going with a cat, the safety of twin rudders, twin engines, and the flotation of twin hulls were a significant part of the decision. Hahaha...yep that sure answers the 2 rudder question. I am familar with the PDQ, I' m sure Bumfuzzle would rather have one. There cat is about 3 years new in N. Zealand they had a delam of the cored hull. The one of the saildrive diesels overheated, etc....... Some cat owners put no-skid on the underside of the bridge deck as it makes a more comfortable platform when or if they turn turtle..... Do you know: http://www.tendervittles.net/index.html on a PDQ Tom and Amy..... Probably one of my most favorite life/sailing adventures posted on the net that I have found, Bumfuzzle is interesting to. Jeff www.sv-loki.com |
|
Mic wrote:
True, but they were still out in it. It just happened that in this case, they had an alternative. If they didn't have the alternative, would they have abandoned ship? I dont know, what do you think? But if they knew what the weather was would they have changed the time they left? Well, when they fell off to SA, they were only 100 miles off and making little progress. Turning away made sense then, but I'm not sure what the point of the hindsight is. I wouldn't bother going out against a 30 knot headwind with an adverse current, but it isn't a disaster when it happens. IIRC, when this happened last to us, we changed plans and found an alternate destination. Almost every time I've been "caught out" there was a forecast for strong winds. Usually we were trying to "thread the needle" between two weather systems. I'm sure my wife wishes a few of the episodes never happened, but I have no regrets and think we did the correct things. We never had a nasty problem, just a few hours of discomfort and perhaps a little anxiety. Also if you read bill_dietrich logs at: http://www.geocities.com/bill_dietri...agnoliaLog.txt Currently in Bahamas, you will see how many boats leave an anchorage and them shortly return... Seen it all the time, been there myself. It doesn't change a thing. You must assume that every now and them you'll be caught in stronger winds than you normally are comfortable in. Frankly, these people are lucky that the weak link is their own nerve (or their stomachs), rather than the boat. Well if you read their logs particularly the ones in New Zealand and the issues with the SA builder of their Wild Cat, be very thankful you have a PDQ. I doubt it has to do with there nerve, rather the fact that they had issues beating to the weather and were making poor distance over ground. Nothing wrong with changing course because of a headwind - that's part of sailing. If you plan to go out there, you had better be able to answer it. Every choice you make for gear and planning will have this in the background. Really? I know exactly what mods I feel would be necessary and satisfied with. I dont believe anyone really knows what the necessary design point is, like you said " somewhere between average winds and Force 5 hurricane" hummm...wouldnt that be about 100 mph spread? Nobody knows for sure, but that can't stop you from making your best guess. Here's an example: do you plan to cruise in hurricane season? If so what would you do if there was a hurricane forecast? Would you anchor? If so, that means you carry at least three anchors and rodes, hopefully one of them well oversized. Thus, if you you don't do that, you've decided that this is not an option for you. Do you have jacklines and harnesses? If not, you've decided you can't handle 10 foot seas, Reef points? Sea anchor? And so on. I tend to be conservative, but I'm also lazy and sometimes get paranoid in unfamiliar situations. But so far, its always worked out. It has been said so many times that in such situations it becomes more of an issue of sailing ability (decisions) than necessarily the boat. A good boat helps. And remember - you've been "surprised" that more boats don't have provisions for emergency rudders. Most of these coastal boats don't, in fact relatively few passage makers nowadays have that. Any passage maker who hasnt considered or mad provision for an emerg rudder.....good luck to them they will need it. True, but there are many ways to jury rig steering gear. And, very, very few boats are designed as ready to go passage makers. Why? Because although many people dream about it, very very few actually do it. I suppose I have to tell eventually ... I have a catamaran, a PDQ 36. One rudder on each hull, off course, tied together with a crosslink attached to each quadrant. One is driven by a cable from the wheel; each can accept a tiller from above. Although space, speed, and stability were the primary factors in going with a cat, the safety of twin rudders, twin engines, and the flotation of twin hulls were a significant part of the decision. Hahaha...yep that sure answers the 2 rudder question. I am familar with the PDQ, I' m sure Bumfuzzle would rather have one. There cat is about 3 years new in N. Zealand they had a delam of the cored hull. The one of the saildrive diesels overheated, etc....... The delam certainly doesn't speak well for the builder, or the surveyor. The saildrive overheated because the water pump impeller lost two vanes - not exactly the manufacturer's fault. They should have added temperature gauges so the overheat could be detected before it got critical. Last summer we saw the temp climb too fast when we left a mooring and were able to return and fix it within an hour. A faulty impeller - it only had 20 hours on it! Again - a matter of decisions. having seen an engine cook its paint off from overheating, I wouldn't go out without temp gauges. Some cat owners put no-skid on the underside of the bridge deck as it makes a more comfortable platform when or if they turn turtle..... Where did you pick up that nonsense? There's been almost no capsizes of cruising cats - less than a dozen in the last 20 years if you only count over 35 feet and actually being cruised by owners. And I've never heard of a capsize that wasn't really caused by too much sail. Do you know: http://www.tendervittles.net/index.html on a PDQ Tom and Amy..... Probably one of my most favorite life/sailing adventures posted on the net that I have found, Bumfuzzle is interesting to. Yes, I've seen their site. We've crossed paths but never actually met. |
On Tue, 14 Jun 2005 20:27:17 -0400, Jeff wrote:
Mic wrote: True, but they were still out in it. It just happened that in this case, they had an alternative. If they didn't have the alternative, would they have abandoned ship? I dont know, what do you think? But if they knew what the weather was would they have changed the time they left? Well, when they fell off to SA, they were only 100 miles off and making little progress. Turning away made sense then, but I'm not sure what the point of the hindsight is. I wouldn't bother going out against a 30 knot headwind with an adverse current, but it isn't a disaster when it happens. IIRC, when this happened last to us, we changed plans and found an alternate destination. Almost every time I've been "caught out" there was a forecast for strong winds. Usually we were trying to "thread the needle" between two weather systems. I'm sure my wife wishes a few of the episodes never happened, but I have no regrets and think we did the correct things. We never had a nasty problem, just a few hours of discomfort and perhaps a little anxiety. Also if you read bill_dietrich logs at: http://www.geocities.com/bill_dietri...agnoliaLog.txt Currently in Bahamas, you will see how many boats leave an anchorage and them shortly return... Seen it all the time, been there myself. It doesn't change a thing. You must assume that every now and them you'll be caught in stronger winds than you normally are comfortable in. Frankly, these people are lucky that the weak link is their own nerve (or their stomachs), rather than the boat. Well if you read their logs particularly the ones in New Zealand and the issues with the SA builder of their Wild Cat, be very thankful you have a PDQ. I doubt it has to do with there nerve, rather the fact that they had issues beating to the weather and were making poor distance over ground. Nothing wrong with changing course because of a headwind - that's part of sailing. I believe they made the right decision, to have done so much tacking in an uncomfortable situation. If you plan to go out there, you had better be able to answer it. Every choice you make for gear and planning will have this in the background. Really? I know exactly what mods I feel would be necessary and satisfied with. I dont believe anyone really knows what the necessary design point is, like you said " somewhere between average winds and Force 5 hurricane" hummm...wouldnt that be about 100 mph spread? Nobody knows for sure, but that can't stop you from making your best guess. Here's an example: do you plan to cruise in hurricane season? Possibly, but not necessarly make a decision on what other cruisers are doing. If so what would you do if there was a hurricane forecast? That really depends, on where you were. Would you anchor? Again depends where you are and what force it is. If so, that means you carry at least three anchors and rodes, hopefully one of them well oversized. Thus, if you you don't do that, you've decided that this is not an option for you. Do you have jacklines and harnesses? Certainly would. f not, you've decided you can't handle 10 foot seas, Reef points? Sea anchor? And so on. I tend to be conservative, but I'm also lazy and sometimes get paranoid in unfamiliar situations. But so far, its always worked out. It has been said so many times that in such situations it becomes more of an issue of sailing ability (decisions) than necessarily the boat. A good boat helps. Yep And remember - you've been "surprised" that more boats don't have provisions for emergency rudders. Most of these coastal boats don't, in fact relatively few passage makers nowadays have that. Any passage maker who hasnt considered or mad provision for an emerg rudder.....good luck to them they will need it. True, but there are many ways to jury rig steering gear. And, very, very few boats are designed as ready to go passage makers. Why? Because although many people dream about it, very very few actually do it. Yep I suppose I have to tell eventually ... I have a catamaran, a PDQ 36. One rudder on each hull, off course, tied together with a crosslink attached to each quadrant. One is driven by a cable from the wheel; each can accept a tiller from above. Although space, speed, and stability were the primary factors in going with a cat, the safety of twin rudders, twin engines, and the flotation of twin hulls were a significant part of the decision. Hahaha...yep that sure answers the 2 rudder question. I am familar with the PDQ, I' m sure Bumfuzzle would rather have one. There cat is about 3 years new in N. Zealand they had a delam of the cored hull. The one of the saildrive diesels overheated, etc....... The delam certainly doesn't speak well for the builder, or the surveyor. yep The saildrive overheated because the water pump impeller lost two vanes - not exactly the manufacturer's fault. They should have added temperature gauges so the overheat could be detected before it got critical. Last summer we saw the temp climb too fast when we left a mooring and were able to return and fix it within an hour. A faulty impeller - it only had 20 hours on it! Again - a matter of decisions. having seen an engine cook its paint off from overheating, I wouldn't go out without temp gauges. Actually as I remember it - when the heat exchanger for the water system was put in the temp warning cable was too short so it was never connected to the buzzer system - it cost them the engine. Some cat owners put no-skid on the underside of the bridge deck as it makes a more comfortable platform when or if they turn turtle..... Where did you pick up that nonsense? There's been almost no capsizes of cruising cats - less than a dozen in the last 20 years if you only count over 35 feet and actually being cruised by owners. And I've never heard of a capsize that wasn't really caused by too much sail. In New Zealand during Bumfuzzle hull repair the yard put no=skid on the bridge deck for that very reason - the underside. Cats are becoming even more popular and have significant advantages for passage making. They are more expense to buy and maintain. And I havent seen one for under 10k like alot of 26 = 28 monohulls. Do you know: http://www.tendervittles.net/index.html on a PDQ Tom and Amy..... Probably one of my most favorite life/sailing adventures posted on the net that I have found, Bumfuzzle is interesting to. Yes, I've seen their site. We've crossed paths but never actually met. I really like their writing style, they are very witty.... |
While reading rec.boats.cruising, I noticed Jeff felt
compelled to write: Mic wrote: Some cat owners put no-skid on the underside of the bridge deck as it makes a more comfortable platform when or if they turn turtle..... Where did you pick up that nonsense? There's been almost no capsizes of cruising cats - less than a dozen in the last 20 years if you only count over 35 feet and actually being cruised by owners. And I've never heard of a capsize that wasn't really caused by too much sail. Heh, another mono -v- multi fable. The fairing time and expense saved by applying non-skid to out of sight areas is the main reason to do this, of course. Nobody actually expects to ever walk on the stuff, but if the unthinkable happens, it's another form of preparation. Reefing early to gust speed and keeping enough sea-room to bear off will keep any modern, well designed multihull right-side-up. Ian |
Mic wrote:
On Wed, 15 Jun 2005 07:09:04 +0700, wrote: As far as bimini design it might be noted that when the Sumatra hit (at night) I had about 10 minutes warning during which the wind went from approximately 7 MPH to 60+. I doubt that a PVC bimini wuold have stayed with the boat -- at least in its original form. That's for sure. Maybe even any bimini... It seems less likely that a dodger will be made from ABS (abs is much better than PVC), regardless should I build any such thing I would certainly do my own tests first. Actually a standard, well-designed stainless tube and canvas bimini will survive hurricane force winds with no problem. A friend has a full cockpit cover on his 50' sailboat. The cover stays on all year. Hurricane force winds have been logged by the instruments every winter, with no damage in 20 years. Sometimes you do get what you pay for. Matt O. |
"Matt O'Toole" wrote in
: Actually a standard, well-designed stainless tube and canvas bimini will survive hurricane force winds with no problem. I've seen power boaters test this theory on their way to the boatramp. Some of those open biminis have been trailered over 70 MPH! Some don't survive, however, mostly those cheap OEM ones the boats came with....(d^:) -- Larry You know you've had a rough night when you wake up and your outlined in chalk. |
Larry W4CSC wrote:
"Matt O'Toole" wrote in : Actually a standard, well-designed stainless tube and canvas bimini will survive hurricane force winds with no problem. I've seen power boaters test this theory on their way to the boatramp. Some of those open biminis have been trailered over 70 MPH! Some don't survive, however, mostly those cheap OEM ones the boats came with....(d^:) Larry You know you've had a rough night when you wake up and your outlined in chalk. Should read: You know you've had a rough night when you wake up and you're outlined in chalk. It reflects badly to see gross elementary errors on a calling card. Please fix it. Please don't take this as criticism, I'm trying to help. Thank you, Terry K My dodger frame is made from fiberglass chimney rods. Flexible, cheap, strong. Terry K |
Terry Spragg wrote:
My dodger frame is made from fiberglass chimney rods. Flexible, cheap, strong. It would be nice if there were an economical source of this rod mat'l avail w/o hacking up cleaning rods, and it has many other great uses. My chimney rod sections are only abt 3/8" or less and I don't think I'd use that for a dodger. A set of chimney rods isn't exactly a retail giveaway, either, and one is stuck with the unusable couplings as well as the rather short lengths. 316L tubing in modest sizes is fairly easy and forgiving to bend in a conduit bender (not the Harry Homeowner type). One may even practice a little with scrap conduit to gain confidence. I'd get the right tubing & sidle up to a commercial electrician on a jobsite at lunchtime. At lot of these guys feel under-appreciated & they might even bend it all up for you for free if you've already lain it out. Remember to pickle/passivate after finished working it all up prior covering. Unless SS is not available in one's area, it seems a false economy to invest the planning, time, fabric & work for a lesser mat'l. |
|
Terry Spragg wrote in
: Please don't take this as criticism, I'm trying to help. Thanks...I was in too much of a hurry and didn't notice it. -- Larry You know you've had a rough night when you wake up and you're outlined in chalk. |
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