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#1
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I would like to know more about poplar plywood.
We did build a small test boat from it (our FL11) and in the shop it looks like a great material. It is light and strong, does not split, bends well and absorbs resin quite well, a very good point for epoxy encapsulated boats. It is a renewable resource and inexpensive. The mechanical characteristics are perfect for our applications. Several professional kayak builders and WEST Systems speak favorably of poplar. I am certain that it is great plywood for small skiffs, kayaks, canoes etc. That point is granted. It may work for some of our sport fishing designs too but here comes the question: How is the resistance to rot and the moisture intake when used in a boat that stays in the water for long periods of time? I am looking at hulls that are completely epoxy saturated and fiberglassed, where the plywood is a core, not plain wooden boats. I just fiberglassed some scrap poplar plywood, will paint the samples and sink them under my dock for a few months to measure changes but I would love to hear from builders with real world experience. Does anybody have a boat build from poplar plywood and how is it doing? Serious answers only please: no flames from "know-it-all" people claiming that this a stupid idea etc. I did my research and compiled a good amount of data about it. No need to tell me that there are different types of poplar, populus and tulipifera or what the bending moment is. What I don't have is information about boats build with that material. Thank you in advance. -- Jacques http://www.bateau.com |
#2
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Not familiar with poplar plywood that actually has poplar as a veneer, but I
am familiar with poplar in "hardwood" form as well as poplar core plywoods (with other hardwood veneers). In general, poplar is one of the woods you simply do not reach for when building anything that may be exposed to water/moisture. Poplar is a popular wood as a secondary wood for the sides and backs of dresser/desk drawers, as good trim that will be painted in a house and in general, it's used anywhere there's a requirement for hardwood, good machinability and paint. While I'm sure you can encapsulate it with resin etc, if moisture does fond the actual wood (and it always does), rapid rot is not a possibility, it's a suretly. Other woods that typically don't find their way to wet uses include maple, alder, red oak etc.... Good luck Rob "Jacques Mertens" wrote in message ... I would like to know more about poplar plywood. We did build a small test boat from it (our FL11) and in the shop it looks like a great material. It is light and strong, does not split, bends well and absorbs resin quite well, a very good point for epoxy encapsulated boats. It is a renewable resource and inexpensive. The mechanical characteristics are perfect for our applications. Several professional kayak builders and WEST Systems speak favorably of poplar. I am certain that it is great plywood for small skiffs, kayaks, canoes etc. That point is granted. It may work for some of our sport fishing designs too but here comes the question: How is the resistance to rot and the moisture intake when used in a boat that stays in the water for long periods of time? I am looking at hulls that are completely epoxy saturated and fiberglassed, where the plywood is a core, not plain wooden boats. I just fiberglassed some scrap poplar plywood, will paint the samples and sink them under my dock for a few months to measure changes but I would love to hear from builders with real world experience. Does anybody have a boat build from poplar plywood and how is it doing? Serious answers only please: no flames from "know-it-all" people claiming that this a stupid idea etc. I did my research and compiled a good amount of data about it. No need to tell me that there are different types of poplar, populus and tulipifera or what the bending moment is. What I don't have is information about boats build with that material. Thank you in advance. -- Jacques http://www.bateau.com |
#3
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Let me take that a little further... Poplar will suck up water like a
sponge if it can find it and will swell and distort. I would not consider it a good wood for holding fasteners either... My advice to the pro, dump the stock, run away from this post, and hope the subject never comes up again... no disrespect intended Jaques', and remember, this is ONLY my opinion. Scotty from SmallBoats.com |
#4
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The poplar plywood I am testing is listed here as "marine" plywood:
http://www.worldpanel.com/eurolite.htm I don't expect much distortion from a 5 ply 6mm ply with melamine glue, saturated with epoxy and fiberglassed. This is plywood used as a core and hasn't much to do with wooden boats technology. I agree that poplar is not a proper material for a wooden boat hull but balsa or foam aren't either. Very large and good boats are build from balsa and foam. Poplar has better characteristics than those core materials but it absorbs moisture. I have concerns about moisture and that is why I posted the question. I have seen boats with balsa strips (not Contourcore) as a core. Balsa also absorbs moisture too and is more tender than poplar but those boats last. Why not poplar? At which point will it's moisture content stabilize in an epoxy matrix? It is already used in wood -epoxy construction, WEST systems endorse it for some applications: http://www.westsystem.com/webpages/e...8/plywood.html Poplar is used for aircraft ply and gest a MIL spec. It is tested for shear resistance after a 3 hour boil test. Not exactly a sponge. I know that this applies to poplar with an Okoume face but shear resistance is all in the core, in the poplar. I also know of some kayak builders who had great succes with poplar and if it could be used for larger boats, that would be great. Don't misunderstand: I am playing the devil's advocate here. I keep an open mind about it and I am not ready to endorse it for such applications. I may if my tests come out positive, I may not if I read about some bad experiences. Thanks for your opinions and I would like to read more. -- Jacques http://www.bateau.com "Backyard Renegade" wrote in message ... Let me take that a little further... Poplar will suck up water like a sponge if it can find it and will swell and distort. I would not consider it a good wood for holding fasteners either... My advice to the pro, dump the stock, run away from this post, and hope the subject never comes up again... no disrespect intended Jaques', and remember, this is ONLY my opinion. Scotty from SmallBoats.com |
#5
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Thanks Paolo.
My poplar plwyood is made in Spain by Garnica, could it be the same? I would love more details. -- Jacques http://www.bateau.com "Paolo Zini" wrote in message ... "Jacques Mertens" ha scritto nel messaggio ... I would like to know more about poplar plywood. ....CUT... Here, in Italy, one poplar ply producer has produced one experimental small quantity of "marine" poplar ply.(that is phenolic glue used... maybe some wood selection) The intended use is/was for boat furniture, not for hull... But, to promote the product the factory as sponsorized one small group of amateur boatbuilders providing the ply for free if used to build one small boat with it... All this is recent and the result may or may not be useful for you... If you want more details, mail me, I will try to find more info. the mail addr. in header is valid. Paolo |
#6
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Thanks Paolo.
My poplar plwyood is made in Spain by Garnica, could it be the same? I would love more details. -- Jacques http://www.bateau.com "Paolo Zini" wrote in message ... "Jacques Mertens" ha scritto nel messaggio ... I would like to know more about poplar plywood. ....CUT... Here, in Italy, one poplar ply producer has produced one experimental small quantity of "marine" poplar ply.(that is phenolic glue used... maybe some wood selection) The intended use is/was for boat furniture, not for hull... But, to promote the product the factory as sponsorized one small group of amateur boatbuilders providing the ply for free if used to build one small boat with it... All this is recent and the result may or may not be useful for you... If you want more details, mail me, I will try to find more info. the mail addr. in header is valid. Paolo |
#7
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![]() My poplar plwyood is made in Spain by Garnica, could it be the same? I would love more details. I don't think so. If memory helps it was one Italian firm. I will collect the info and inform you. Paolo |
#8
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William R. Watt ) writes:
the poplar we have here is very soft fast growing and not used on boats. there are different varieties of poplar. out of curiosity I checked a couple of my reference books ("Native Trees of Canada (1946) Dept. Mines and Resources, "The Forest Trees of Ontario" (1986) Minstry of Natural Resources) and poplar is (was?) used for veneers plywoods, as well as matches, boxes, plywood, and some lumber on the praries where little else grows. Poplars are also called "cottonwood" as well as "aspen" and they are a close relative of willows. All the varieties are lightweight, soft, not strong, and porous. Most are described as fine textured and white in colour which would explain their use as veneer. -- ------------------------------------------------------------------------------ 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 |
#9
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We are talking about two different things.
The plywood we are testing is not a buck a truckload, it is not plain cheap wood. Anyway, I got at least one interesting response about a similar experiment (thanks Paolo) and since I am very stuborn, I will keep testing. What keeps me going is the memory of all the people who were laughing at my first boat designed for Airex. Foam for a boat hull? It will never work they said . . . -- Jacques http://www.bateau.com "Backyard Renegade" wrote in message om... "Jacques Mertens" wrote in message ... The poplar plywood I am testing is listed here as "marine" plywood: http://www.worldpanel.com/eurolite.htm I don't expect much distortion from a 5 ply 6mm ply with melamine glue, saturated with epoxy and fiberglassed. I am playing the devil's advocate here. I keep an open mind about it and I am not ready to endorse it for such applications. I may if my tests come out positive, I may not if I read about some bad experiences. Thanks for your opinions and I would like to read more. -- Jacques http://www.bateau.com Well, I still think it is a bad idea, if for no other reason than that the stuff is a buck a truckload up here in the NE and I have *never* heard of *anyone* using is locally for anything to do with boats... Scotty from SmallBoats.com |
#10
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![]() Anyway, I got at least one interesting response about a similar experiment (thanks Paolo) and since I am very stuborn, I will keep testing. Do you have received my mail? I have sent it in the middle of virus storm (i have received UNDREDS of virus mails!) and you can have lost it... Paolo |
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