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American White Oak vs Cedar in clinker construction
I've just got a quote back from a company on planking stock. The
White Oak came in at around £20 cheaper (negligible) and therefore price is not a consideration. The HMSO Handbooks of Hard and Soft woods make the White Oak sound like a very good material, particularly with regard to bending with a downside of a tendency to dull tools and variability in quality dependant on the precise species and environment. It made the Cedar out to be a rather brittle material, although easy to work, although no precise mechanical properties are available in my edition (1957 reprinted '60). Appearance is a secondary consideration to strength in this application and ease of working. Which would you consider to be the better timber to use for a 9foot stem dinghy expected to last a while, given that this is my first foray into traditional construction? I would also be grateful if suggestions could be made about suitable centreline materials, again, strength and suitability being primary to appearance. Leather suggests a mixture of Mahogany (Utile is available), Iroko or Oak in his book "Clinker Boatbuilding" but I'd be interested in other's opinions. Thanks for your time and suggestions. Al |
American White Oak vs Cedar in clinker construction
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American White Oak vs Cedar in clinker construction
I know that white oak used to be used sometimes for planking in Scandanavian
clinker construction, and made for hell-for-stout but heavy hulls. It would make for a rather heavy dinghy, and the planks would likely require steam bending at least at the bow. You might consider Alaskan yellow cedar for the planking; it's light and strong, and I wouldn't call it brittle. Port Orford cedar, if available to you, tends to split lengthwise down a considerable length of the plank if something happens to it to cause it to split, but Alaskan yellow has more interlocked grain and damage remains more localized. White oak is great for the keel timbers and stem, green white oak if carefully chosen for clearness and grain runout would steam-bend quite well for the frames. Another good choice for the steam-bent frames is locust. In your dreams, you'd find a white oak natural crook for the stem and transom knees. White oak, on the other hand, doesn't like being wet all the time, and a keel of white oak might take some damage from rot if water is left in the bottom of the boat a lot. A superb keel timber is purpleheart, but it's extremely difficult to work with hand tools and even heavier than white oak. Some folks like to get out the sheer strake from Honduras mahogany, both for strength and for appearance. Mahogany is also a good choice for the transom and transom framing, the stringers for the thwarts, and the thwarts themselves. Teak floorboards, perhaps 5/16" thick in order to take the slight bend, could be left altogether unfinished so as not to be slippery when wet, but would not deteriorate from exposure to weather. If you should use mahogany for the sheer strake, you may have to steam-bend the part of the plank that takes the bend at the bow. By the way, avoid so-called Philippine mahogany - it's not a true mahogany but actually a type of tropical cedar and is a totally inferior boat building wood. As to white oak species, as I've sometimes heard said, "White oak seems to grow on a lot of different kinds of stumps." The species you're after is quercus alba. Hope this helps, Tom Dacon "Al" wrote in message om... I've just got a quote back from a company on planking stock. The White Oak came in at around £20 cheaper (negligible) and therefore price is not a consideration. The HMSO Handbooks of Hard and Soft woods make the White Oak sound like a very good material, particularly with regard to bending with a downside of a tendency to dull tools and variability in quality dependant on the precise species and environment. It made the Cedar out to be a rather brittle material, although easy to work, although no precise mechanical properties are available in my edition (1957 reprinted '60). Appearance is a secondary consideration to strength in this application and ease of working. Which would you consider to be the better timber to use for a 9foot stem dinghy expected to last a while, given that this is my first foray into traditional construction? I would also be grateful if suggestions could be made about suitable centreline materials, again, strength and suitability being primary to appearance. Leather suggests a mixture of Mahogany (Utile is available), Iroko or Oak in his book "Clinker Boatbuilding" but I'd be interested in other's opinions. Thanks for your time and suggestions. Al |
American White Oak vs Cedar in clinker construction
Nobody mentioned it, so I will. If you are using epoxy, be aware that white
oak can sometimes work, sometimes not. I've heard a lot of arguments as to why, but I've not seen a lot of answers for how to guarantee that epoxy will stick to white oak as well as it sticks to other types of woods. White oak is more rot resistant than red, so don't be tempted to use red oak because it glues better. Brian -- My boat project: http://www.advantagecomposites.com/tongass "Al" wrote in message om... I've just got a quote back from a company on planking stock. The White Oak came in at around £20 cheaper (negligible) and therefore price is not a consideration. The HMSO Handbooks of Hard and Soft woods make the White Oak sound like a very good material, particularly with regard to bending with a downside of a tendency to dull tools and variability in quality dependant on the precise species and environment. It made the Cedar out to be a rather brittle material, although easy to work, although no precise mechanical properties are available in my edition (1957 reprinted '60). Appearance is a secondary consideration to strength in this application and ease of working. Which would you consider to be the better timber to use for a 9foot stem dinghy expected to last a while, given that this is my first foray into traditional construction? I would also be grateful if suggestions could be made about suitable centreline materials, again, strength and suitability being primary to appearance. Leather suggests a mixture of Mahogany (Utile is available), Iroko or Oak in his book "Clinker Boatbuilding" but I'd be interested in other's opinions. Thanks for your time and suggestions. Al |
American White Oak vs Cedar in clinker construction
On Sat, 20 Sep 2003 05:19:16 GMT, "Brian D"
wrote: Nobody mentioned it, so I will. If you are using epoxy, be aware that white oak can sometimes work, sometimes not. I've heard a lot of arguments as to why, but I've not seen a lot of answers for how to guarantee that epoxy will stick to white oak as well as it sticks to other types of woods. White oak is more rot resistant than red, so don't be tempted to use red oak because it glues better. That's right. 'Course, with any luck, one needn't use epoxy at all in this kind of construction. |
American White Oak vs Cedar in clinker construction
Nobody mentioned it, so I will. If you are using epoxy, be aware that white
oak can sometimes work, sometimes not. I've heard a lot of arguments as to why, but I've not seen a lot of answers for how to guarantee that epoxy will stick to white oak as well as it sticks to other types of woods. White oak is more rot resistant than red, so don't be tempted to use red oak because it glues better. I'm using clinker construction in a bid to keep glue/resin usage to a minimum. I don't particularly enjoy working with epoxies, but I do enjoy working with mechanical fastenings and good quality wood. I may have to laminate knees however as I can't come up with any sources for grown crooks, and the stem will have to be, at least in part, a lamination. As far as the cedar goes, I only have Western Red available to me, I apologise for not specifying this earlier, does this alter your analysis? As a matter of interest, why are you recommending the cedar over the oak, is it just ease of working? Thanks Al |
American White Oak vs Cedar in clinker construction
Brian D wrote: Nobody mentioned it, so I will. If you are using epoxy, be aware that white oak can sometimes work, sometimes not. I've heard a lot of arguments as to why, but I've not seen a lot of answers for how to guarantee that epoxy will stick to white oak as well as it sticks to other types of woods. I suspect that the problem lies in the tannic acid in the wood. I've been working with green red oak lately, which discolors tool beds and cutting tools, and the wood ends up with black streaks where you cut it with steel tools or run it across an iron tool bed. Anyway, the point is that epoxy is neutralized by acids, which is why vinegar is used to clean up uncured epoxy spills. It neutralizes the epoxy so it will not cure, making it easier to remove. I suspect that the same thing is happening with the tannic acid in oak. -- Regards Brian |
American White Oak vs Cedar in clinker construction
Al ) writes:
...It made the Cedar out to be a rather brittle material, although easy to work, although no precise mechanical properties are available in my edition (1957 reprinted '60). Appearance is a secondary consideration to strength in this application and ease of working. eastern white cedar is actually durable and easy to work. that's why natives used it for the ribs and lining of birchbark canoes over all the other native woods avaiable to them. clear, staight grained cedar was split into 1/8 thick lining planks by hand. I owned a 22 year old cedar skiff from www.cedarboats.com as a boy. Whenever my grandfather wanted to whittle anything he'd pick out a piece of cedar from the wood pile. Easiest wood to split to kindle a fire. I assume western red cedar would have similar qualities. I use the red cedar in the framing on my small cheap plywood boats along with lumberyard spruce. -- ------------------------------------------------------------------------------ William R Watt National Capital FreeNet Ottawa's free community network homepage: www.ncf.ca/~ag384/top.htm warning: non-freenet email must have "notspam" in subject or it's returned |
American White Oak vs Cedar in clinker construction
Hi
"P.C. Ford" skrev i en meddelelse ... On 20 Sep 2003 04:30:27 -0700, (Al) wrote: Snip As far as the cedar goes, I only have Western Red available to me, I apologise for not specifying this earlier, does this alter your analysis? As a matter of interest, why are you recommending the cedar over the oak, is it just ease of working? In the US, as far as I know, oak was never used for small boat planking. Oak is heavy and hard to work. It is stronger of course. The strength is just not needed. The Lawley yard had a saying about their thin scantlings on their dinghies. Something to the effect that if the boat is going on the rocks, the difference between 3/8 and 7/16 is not important. Now Oak work different in thin planks. Oak and Ash have some simularity with these matters, but a thin Oak plank is a different thing than a softwood or near softwood . Oak don't like it to dry and ofcaurse you can prefere a good Larch from a bad Oak, but done right , and with top quality wood Oak add more than just the good looks, it will drain your bank account, unless you master just a few skills, Oak is perfect for Lapstrake boats, and with Epoxy , you can lenghten any plank so you can experience a lapstrake boat without butts, in Oak , where the rule is, that this can be 2/3 thickness now it is stronger wood. Still why do you bother, Computer drawings with unfolded planks do exist with Cyber-Boat, but from my best knowleage , most unfolding is done from smothened single curved skins . You can hardly find modern designs, that is projected and the most "modern" lapstrake design, that you would reconise, is the danish folkboat . Still with materials you have a wide choice even the computer thing is fiddeling and square box in inches , ---------- Nice boats was once build in this smart building method, even it still is difficult to project in 3D ,you can chose high quality , but please read about Oak before you decide, as what you need is the true gray Oak not the "Oak" that is often used with furniture , do it carry acid and is bone hard or is it a weak specie for outdoor use even nice and without knots ; with Oak you can ask cirain qualities. BTW. --------- A Lapstrake is the one that carry less frames , acturly they are build without, and the ribs put in after, this acturly define the Lapstrake method , compared other methods. With Cyber-Boat you will find true 3D Lapstrake computer models, being the basis for the unfolded planks , but I guess no one even care that with 3D-H you can complete the Lapstrake method, with a perfect 3D-Honeycomb framework, at last one reliable, that can be cut from sheet material, Anyway the 3D-H building method, that offer you to build a new WTC without the weak trusses and hangers, proberly will produce very few true Lapstrake boats. Mahogony is what I prefered when I made boats .Only later I taken lame cheap chipwood into consideration, and acturly offer plans for a tremendures Longboat , that you can build extremely cheap , the plans are free ,the plans don't care if it is plywood or crome plated Gold , but if you realy want to make good use of thin Oak planks, why didn't you check the full-scale plans here ; http://w1.1396.telia.com/~u139600113/ Or ; http://groups.yahoo.com/group/Cyber-Boat/ O.T. you can se what 3D-H can produce , beside boat frames ; http://www.designcommunity.com/scrapbook/2806.html P.C. http://groups.yahoo.com/group/structure-testbench/ Check Foto's folder for design. |
American White Oak vs Cedar in clinker construction
Oak don't like it to dry
am I reading the correct implication that oak will tend to split when dried out, but that softwood is likely to cope better and split less? Still why do you bother, partly because I want a challenge, partly because I want to work with high quality materials and avoid resins (my day job is making resins... I see enough of them and read enough MSDS' to put me off for life), but I think mostly because there is something about a "traditionally" constructed craft that gets me excited in a way that composite boats don't. S&G definitely has it's place, and epoxy/wood composite boats are excellent for light weight, ease of construction, ease of maintenance, but _for_me_ they are not as interesting or stimulating as clinker craft. And a very small perverted part of me wants to do it just because various authorities think it'll be far too hard for me ;-) Life is for living! Al |
American White Oak vs Cedar in clinker construction
Hi
"Al" skrev i en meddelelse om... Oak don't like it to dry am I reading the correct implication that oak will tend to split when dried out, but that softwood is likely to cope better and split less? Still why do you bother, partly because I want a challenge, partly because I want to work with high quality materials and avoid resins (my day job is making resins... I see enough of them and read enough MSDS' to put me off for life), but I think mostly because there is something about a "traditionally" constructed craft that gets me excited in a way that composite boats don't. S&G definitely has it's place, and epoxy/wood composite boats are excellent for light weight, ease of construction, ease of maintenance, but _for_me_ they are not as interesting or stimulating as clinker craft. And a very small perverted part of me wants to do it just because various authorities think it'll be far too hard for me ;-) Life is for living! Al Sound you are not fanatic about it, and you shuldn't be. As with just a small quantity epoxies, you have the chance to make those small repairs, that the average person don't know is there. The Lapstrake method on the other hand, leave you the oppotunity to perform a structure that is much more advanced than most think, ------- but that the tailored planks will fit without thruout resistance is somthing important to remember, as sure you can force a plank edgevise , but you pay somhow if you are not keen about how things shuld be and could be. You are quite right about my warning about drying Oak, but as with all wood this also is about knowing the material and knowing the time needed to make sure the surface is not drying faster than the core, ----------- please let me give an example. Normaly wet wood just sawn, is still "secured" with a plank piece nailed to the end of the plank. When you ask why you get two ansvers ; first is that the nails will hold the plank from splitting , and that is silli , as when the plank dry it get more narrow while the plank piece with the nails keep the same length and by this fact, acturly help splitting the plank. Second ansver is that the plank nailed to the end of the wood, prevent the endwood piece to dry out to fast. But even this is true , then why not just do it as it shuld be done , replace the nails and plank piece with a layer of thick paint. Guess you have all chances to succes , if you find some realy old books about wooden boat building, but as you proberly know, it is better to trust your own judgement. A small quantity epoxy can save a perfect plank and I se nothing wrong, using a few grams epoxy to do so. -------- that's how I se Epoxy, not as somthing that is more than 50 pct. and where everything else shuld be depandant on that, but as a perfect glue. Not somthing to cover your missing skills but somthing that allow for perfect materials and skills. P.C. http://www.designcommunity.com/scrapbook/2806.html |
American White Oak vs Cedar in clinker construction
Go for it. I think one of the reasons that you see resins being glopped
around so much is because it is getting so darn hard, and expensive, to find good wood anymore. At least in any length ... Brian PS: I'm an epoxy glopper, but I will most definately go the traditional route at some point and take my time with a more artistic expression of boatology... which probably means clinker construction (MHO). -- My boat project: http://www.advantagecomposites.com/tongass "Al" wrote in message om... Oak don't like it to dry am I reading the correct implication that oak will tend to split when dried out, but that softwood is likely to cope better and split less? Still why do you bother, partly because I want a challenge, partly because I want to work with high quality materials and avoid resins (my day job is making resins... I see enough of them and read enough MSDS' to put me off for life), but I think mostly because there is something about a "traditionally" constructed craft that gets me excited in a way that composite boats don't. S&G definitely has it's place, and epoxy/wood composite boats are excellent for light weight, ease of construction, ease of maintenance, but _for_me_ they are not as interesting or stimulating as clinker craft. And a very small perverted part of me wants to do it just because various authorities think it'll be far too hard for me ;-) Life is for living! Al |
American White Oak vs Cedar in clinker construction
It's like any hobby... if you look around, you can find boats cheap...
IMO, cheaper than you can build 'em, if you account for your time especially), and often cheaper than the materials. I'm building them for the experience, taxing my skills, the sense of accomplishment, etc. Ed Brian D wrote: Go for it. I think one of the reasons that you see resins being glopped around so much is because it is getting so darn hard, and expensive, to find good wood anymore. At least in any length ... Brian PS: I'm an epoxy glopper, but I will most definately go the traditional route at some point and take my time with a more artistic expression of boatology... which probably means clinker construction (MHO). |
American White Oak vs Cedar in clinker construction
(Al) wrote in message I may
have to laminate knees however as I can't come up with any sources for grown crooks, and the stem will have to be, at least in part, a lamination. Al If you are looking for grown crooks, Try: http://www.newmansknees.com/ Disclamimer, they are a client. Scotty from SmallBoats.com |
American White Oak vs Cedar in clinker construction
Sound you are not fanatic about it, and you shuldn't be.
Epoxy is a tool like any other in my book. If I hit a situation during the project in which epoxy is the sensible route to take (against my definition of sensible. Most people would say that building using the easiest, lightest weight method would be sensible... killjoys ;-p), I will make use of it. I may well use it at some point in the stem to avoid the hassles of stop waters. However, this is a boat that will shrink and swell, that will respond to the temperature, to it's environments. Copper has a little give in it whereas epoxy will tend to be pretty immobile, I suspect that there is potential over time for the epoxy to induce stress fractures in the timber. And at the end of the day, copper/timber is an old method that has stood up well to time. Epoxy hasn't had the same kind of long term (centuries) testing. Anyhow, plans are in the post. Thanks to Pat for pointing out crook supplier, I'll look into that when I've worked out my requirements. Thanks for all comments, right now I'm looking at western red cedar for planking, whatever I can get for knees etc. (probably oak from the literature). Centreline is still in question, although I'm tempted by Iroko or Utile as what I've read indicates good mechanical properties coupled with good looks. Ribs are hopefully suitable bending oak, failing that, probably ash. Foils are tricky, Leather suggesting "Mahogany" which leads me back in the Iroko/Utile direction. Any thoughts? Oars and spars are of course in Spruce. Thwarts are looking like Utile/Iroko, again for looks... I weigh a paltry 11stones so mechanical properties are not a big problem. Can anyone spot any major problems in the above list? Final question, I'm looking at getting hold of something like a 10 foot 3x6 as the backbone of my building jig. Presumably I can get away with Pine/Fir for this as long as I check it to avoid warp and plane it true? Thanks to everyone, there aren't many newsgroups I would consider as a source for valuable advice (used in conjunction with suitable literature), but I have learned over the past few years to have tremendous respect for more or less every poster here. Thanks. Al |
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