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#1
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Using laminated veneer?
Hello -
I would like to build a dinghy or small sailboat using the cold-molded plywood method, sometimes called laminated veneer. I have looked a couple of books (Ruel Parker's and Hub Miller), but their emphasis seems to be on large yachts. Since I want to make a small boat, neither book answers the questions about ; 1. Selection of veneer, ie, wood type, appropriate thickness, number of plys (plies?), etc. 2. Mold method set-ups which are more suited to small boats. 3. The best method for making and setting up stems and transoms. 4. Adhesives - must if be epoxy? How about using the "construction" types glues? 5. General "comfort talk" to aspiring cold-molders. Can anybody help? Your specific suggegestions or references will be greatly appreciated. Thanks, Joseph |
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#2
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Using laminated veneer?
"jotis" ) writes:
Hello - I would like to build a dinghy or small sailboat using the cold-molded plywood method, sometimes called laminated veneer. 4. Adhesives - must if be epoxy? How about using the "construction" types glues? for a small boat kept under cover when not in use the construction polyurethane or the plastic resin (urea formaldehyde) are okay. the plastic resin has to be a tight fit and over 70 deg F to cure. I've used both on small plywood boats (not cold moulded). I don't have many clamps and prefer to screw-and-glue instead for gunwales, chines, etc. TF Jones wrties about a cold moulded kayak bottom made with cedar veneer and plastic resin which was still tight after 9 years. It was kept in a shed when not in use. you can test glues by buying small quantities and gluing up small pieces. I normally do that with any new building method or material. -- ------------------------------------------------------------------------------ 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 |
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#4
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Using laminated veneer?
The veneer cold-molding process is well documented in the Gougeon book.
(Western red) cedar veneer was the preferred material. Eventually, it was figured out that the addition of a light fiberglass skinn was needed to protect the soft cedar. The strip canoe folks figured out that if there was a structural glass skin on both sides, multiple layers of wood core weren't necessary and the skins gave adequate 'thwartship strength. So, for boats under thirty feet, cold-molding with veneers has been largely replaced by strip composite construction. Less labor, cheaper materials, equal product. That's why it's now hard to find cedar veneers. jotis wrote: Hello - I would like to build a dinghy or small sailboat using the cold-molded plywood method, sometimes called laminated veneer. I have looked a couple of books (Ruel Parker's and Hub Miller), but their emphasis seems to be on large yachts. Since I want to make a small boat, neither book answers the questions about ; 1. Selection of veneer, ie, wood type, appropriate thickness, number of plys (plies?), etc. 2. Mold method set-ups which are more suited to small boats. 3. The best method for making and setting up stems and transoms. 4. Adhesives - must if be epoxy? How about using the "construction" types glues? 5. General "comfort talk" to aspiring cold-molders. Can anybody help? Your specific suggegestions or references will be greatly appreciated. Thanks, Joseph |
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#5
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Using laminated veneer?
Hello Jim-
Thank you for your very interesting analysis of why it is so difficult to get much information about cold-molding; it looks like it has become obsolete. Nevertheless, the process appears to be so fascinating that I hate to discard the idea altogether. Frankly, one of the benefits that I perceived with cold-molding was that it would not require a skin of fiberglass (the very thought of which makes my skin quiver), but I am coming to realize that and education - and some experience with - fiberglass is becoming a necessity. There is a good deal of information about strip planking around, and will reconsider that mode of construction. Thanks again, Joseph "Jim Conlin" wrote in message ... The veneer cold-molding process is well documented in the Gougeon book. (Western red) cedar veneer was the preferred material. Eventually, it was figured out that the addition of a light fiberglass skinn was needed to protect the soft cedar. The strip canoe folks figured out that if there was a structural glass skin on both sides, multiple layers of wood core weren't necessary and the skins gave adequate 'thwartship strength. So, for boats under thirty feet, cold-molding with veneers has been largely replaced by strip composite construction. Less labor, cheaper materials, equal product. That's why it's now hard to find cedar veneers. |
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#6
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Using laminated veneer?
Certainly the Gougeon book is essential reading if you're contemplating a
cold-molded hull. If you are still interested , the next step is finding the needed veneers. I recently bought some LOVELY honduras mahogany veneer from Edensaw in Seattle. If you want to avoid having to do a glass overlay, consider using a firmer species than cedar for the outermost ply. jotis wrote: Hello Jim- Thank you for your very interesting analysis of why it is so difficult to get much information about cold-molding; it looks like it has become obsolete. Nevertheless, the process appears to be so fascinating that I hate to discard the idea altogether. Frankly, one of the benefits that I perceived with cold-molding was that it would not require a skin of fiberglass (the very thought of which makes my skin quiver), but I am coming to realize that and education - and some experience with - fiberglass is becoming a necessity. There is a good deal of information about strip planking around, and will reconsider that mode of construction. Thanks again, Joseph "Jim Conlin" wrote in message ... The veneer cold-molding process is well documented in the Gougeon book. (Western red) cedar veneer was the preferred material. Eventually, it was figured out that the addition of a light fiberglass skinn was needed to protect the soft cedar. The strip canoe folks figured out that if there was a structural glass skin on both sides, multiple layers of wood core weren't necessary and the skins gave adequate 'thwartship strength. So, for boats under thirty feet, cold-molding with veneers has been largely replaced by strip composite construction. Less labor, cheaper materials, equal product. That's why it's now hard to find cedar veneers. |
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#7
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Using laminated veneer?
"jotis" wrote in message ... Hello - I would like to build a dinghy or small sailboat using the cold-molded plywood method, sometimes called laminated veneer. I have looked a couple of books (Ruel Parker's and Hub Miller), but their emphasis seems to be on large yachts. Since I want to make a small boat, neither book answers the questions about ; 1. Selection of veneer, ie, wood type, appropriate thickness, number of plys (plies?), etc. 2. Mold method set-ups which are more suited to small boats. 3. The best method for making and setting up stems and transoms. 4. Adhesives - must if be epoxy? How about using the "construction" types glues? 5. General "comfort talk" to aspiring cold-molders. Can anybody help? Your specific suggegestions or references will be greatly appreciated. Thanks, Joseph The Mirror sailing/rowing/small outboard design uses 1/8" plywood and very basic cold moulding. hard Chines, etc. Plenty of websites and plans available. Its not a multi laminate with cross plys. I've been experimenting with three western red cedar strips of 1/8" thick by 1" wide interlaced with carbon fibre and epoxy. A 3' length will support me at 100kgs and is very rigid. -- www.bribieisland4x4hire.com VW Kombi Camper Buy Backs Landcruiser Troopy - Toyota Hilux Crew Cab Mitsubishi Pajero - Landrover V8 Swag Camper |
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#8
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Using laminated veneer?
"jotis" ) writes:
What I wanted to know was the suitability of smearing the construction glue between layers of each veneer ply as is applied to the layer underneath. I don't know how to evaluate that. I've laminated doorskin lauan ("mahogony") plywood with PL Premium. There is a photo on my website under "Boats", "folding cabin". You squeeze a bead on with the caulking gun and then spread it with a putty knife or similar. I've never made a cold moulded hull. If you are cold moulding there would likely not be enough stiffness in the first layer of veneer to spread it on the hull so you would spread the adhesive on the second layer strip instead. I laminated the transom of the Dogskiff on my website with plastic resin glue. Only photos of the finished boat on the website for that one. The boat was launched spring of1999 and the transom is fine. A guy named Steve Ladd built a 12 ft cold moulded cedar and fibreglass boat called "Squeak" for $2000 in 1990 and spent 3 years sailing it in the USA and South America. The boat was decked over with a cockpit and weighed 250 pounds. There are some photos on the Intenet. His book is called "Three Years in a Twelve Foot Boat". the book does not describe building the boat. BTW the specially cut cedar strips for "stripper" construction are pretty expensive compared to cutting your own strips of plywood veneer for cold moulding. You also need moulds 12-14 inches apart because the strips are so flexible. They have little strength of their own. That comes from the fibreglass that goes over them. You can compare prices. I think you can find stripper prices at www.bearmountianboats.com. -- ------------------------------------------------------------------------------ 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 |
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#9
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Using laminated veneer?
"jotis" wrote in message ...
Hello Jim- Thank you for your very interesting analysis of why it is so difficult to get much information about cold-molding; it looks like it has become obsolete. Nevertheless, the process appears to be so fascinating that I hate to discard the idea altogether. Frankly, one of the benefits that I perceived with cold-molding was that it would not require a skin of fiberglass (the very thought of which makes my skin quiver), but I am coming to realize that and education - and some experience with - fiberglass is becoming a necessity. Here is an area I can address in this thread... Oh goody! Anyway, this should not be a point of anxiety (sp?). With the Epoxy technology and calibrated pumps, this is only a question of patience and preperation. The main thing is to prepare the surface properly first. Then cut out your fiberglass, leaving a couple of inches extra all the way around. Next roll up one side of the glass and spread a slightly thickened layer of epoxy in it's place (this can be done easily with a disposable paint roller). Next roll the glass back over the wet area, and start to wet out the glass with the same paint roller and a unthickened layer of epoxy. Next, roll up the other side of the glass, and do the same thing. Remember, it is a lot easier to draw goo up through glass than it is to drive it down in. Typically, I apply probably 75% of the goo I will use in an area, before the fabric is laid down, then draw it up through the glass. This may seem elementry to some but I always mention it as it took me close to a year to figure this out, of course when I did, I felt like a real dolt  Really, using pumps, paint rollers and proper preperation, glassing a small hull can actually be one of the easiest parts of building a boat. Did not say most fun, just easiest. Scotty from SmallBoats.com There is a good deal of information about strip planking around, and will reconsider that mode of construction. Thanks again, Joseph "Jim Conlin" wrote in message ... The veneer cold-molding process is well documented in the Gougeon book. (Western red) cedar veneer was the preferred material. Eventually, it was figured out that the addition of a light fiberglass skinn was needed to protect the soft cedar. The strip canoe folks figured out that if there was a structural glass skin on both sides, multiple layers of wood core weren't necessary and the skins gave adequate 'thwartship strength. So, for boats under thirty feet, cold-molding with veneers has been largely replaced by strip composite construction. Less labor, cheaper materials, equal product. That's why it's now hard to find cedar veneers. |
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#10
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Using laminated veneer?
Hello Scotty-
Many thanks for the clearly expressed information. I hope it really is as easy as you make it out to be. Regards, Joseph Here is an area I can address in this thread... Oh goody! Anyway, this should not be a point of anxiety (sp?). With the Epoxy technology and calibrated pumps, this is only a question of patience and preperation. The main thing is to prepare the surface properly first. Then cut out your fiberglass, leaving a couple of inches extra all the way around. Next roll up one side of the glass and spread a slightly thickened layer of epoxy in it's place (this can be done easily with a disposable paint roller). Next roll the glass back over the wet area, and start to wet out the glass with the same paint roller and a unthickened layer of epoxy. Next, roll up the other side of the glass, and do the same thing. Remember, it is a lot easier to draw goo up through glass than it is to drive it down in. Typically, I apply probably 75% of the goo I will use in an area, before the fabric is laid down, then draw it up through the glass. This may seem elementry to some but I always mention it as it took me close to a year to figure this out, of course when I did, I felt like a real dolt Really, using pumps, paint rollers and proper preperation, glassing a small hull can actually be one of the easiest parts of building a boat. Did not say most fun, just easiest. Scotty from SmallBoats.com |
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