Composite transom...composite stringers...what about the floor?

outonbizniz	My goal is to rebuild my boat with no wood left in her. My transom and stringers will be Seacast. The floor..I'm not too sure about. Has anyone used anything other that plywood and epoxy? If so how did it turn out? I would ask how much it cost but since I'm already using Seacast I guess price isn't going to stop me (though my wallet could).	2002-05-23
suzukidave	I would stick with a wood floor deck if you are putting floatation foam under it. Otherwise if the deck or hull ever leaks you will have a heck of a time removing the floor to remove and replace the wet foam.	2002-05-23
outonbizniz	If I do have to use wood...I will be glassing it into place. I was thinking of something like masonite. I need something that comes in a sheet like plywood...but that is waterproof.	2002-05-23
blifsey	How about King Starboard? Try http://www.kingstarboard.com I think it is pretty pricey! BL...	2002-05-23
outonbizniz	BLIF...Thanks a lot!!! That's exactly what I was looking for. That does it! There will be NO WOOD in my boat! HAHA	2002-05-23
outonbizniz	In case anyone else is curious: I just called KingStarBoard. A 54"x96"x3/4" sheet of the AS (anti slip patern in the top) weighs 135 LBS and costs US$420 - US$450. The price is a bit steep and sound like it will weigh more that wood.	2002-05-23
outonbizniz	BLIF...Thanks a lot!!! That's exactly what I was looking for. That does it! There will be NO WOOD in my boat! HAHA	2002-05-23
djohns19	Ouonbizniz, I knew that stuff was expensive. Have you thought about FRP (Fiberglass Reinforced Plywood)? That's the stuff that truck body sidewalls are made of along with semi trailers. It's tough, and is completely waterproof as long as you epoxy the ends where you have cut. You should be able to buy it at truck/trailer repair centers. They should at least be able to tell you where they get it.	2002-05-23
outonbizniz	Another great idea. I knew there had to be a ton of alternative materials. I'll be carpeting over whatever I use so looks aren't very important. BTW...the kingstarboard won't accept glue to hold down carpet (although for that price I wouldn't want to cover it). Thanks Again	2002-05-24
tmcalavy	If/when I ever get around to doing the same project, I'm going to use polyboard...a plastic plywood. It's fairly expensive, about 2X that of regular marine grade plywood, but it's completely impervious to water and handles just like wood. You may have to call around to find it in retail places, but it's getting more and more common.	2002-05-24
outonbizniz	Here's a link to the Polyboard you mentioned. It's MUCH CHEAPER than KingStarBoard and you can do anything to it that you can do to plywood. 4'x8'x1/2" = US$41.00	2002-05-24
outonbizniz	I forgot the link...here you go. Sorry. http://www.renewresources.com/polyboard.html	2002-05-24
outonbizniz	I forgot the link...here you go. Sorry. http://www.renewresources.com/polyboard.html	2002-05-24
SCO	After looking at the polyboard site, I wonder whether polyboard will hold its shape. It looks like the skateboard ramp frame is made of plywood. also: may have to be mechanically fastened only. I bet epoxy/polyester won't stick to it. 12 times tougher, ok I'll buy that it is difficult to destroy with a hammer, but toughness is not the same as strength. If you suspend a sheet between 2 beams, will it bow more than the same thickness and weight of plywood? How will a hot day in the sun treat it? There is a reason that plywood is the standard building material. I bet you could design for this material in a boat, but caution if you are trying to replace plywood in an application designed for plywood. Maybe you can get some test strips to check it out.	2002-05-28
crab bait	Sound wisdom ,,,SCO	2002-05-28
outonbizniz	SCO...Since it is not extremely expensive and I can get it locally I will be performing a couple of tests before I buy into it. Thanks for the advice.	2002-05-28
Hawkeye1	What ever you use you need to be able to glass it into the boat to make sure you don't get water down below. This plactic stuff and especially starboard might not glue or seal well. I would use 2 layers of ext 1/4" luan. Epoxy coat the bottom, epoxy the the 2nd sheet on top of the 1st one, overlaping the seams, then cover all with a layer of glass and epoxy. You won't have to worry about rot with the epoxy. You have to make sure any hole are sealed well. The luan is about 25 lbs a sheet and is easy to work with. That what I just did the 12 x 7 floor in my 23'er with and it came out great.	2002-05-28
blifsey	Hawkeye1, Why 2 sheets of 1/4 vs 1/2 or 3/4 exterior or marine grade ply? Is it to stagger seams for strength? Easier to handle? Just curious... BL...	2002-05-28
Franki	Hi guys.. <joke> wonder how the one inch thick stuff would go in a transom??? :-) </joke> I just emailed them and asked if it bonds to fiberglass... be interesting to know if it does... Wood is slowly moving out of the boating industry.. there are alot of boats being touted as "wood free" so that's the way things are going.. I am always looking for new and innovative products and keep an open mind till I have a good reason not to.. let us know how your tests go outonbizniz. regards Frank	2002-05-28
outonbizniz	Will do Frank. It'll be this weekend before I will have time to catch the lumber yard that carries the stuff open....it may be easier (cheaper) to catch the yard when it's closed.	2002-05-28
Hawkeye1	Thats right BL you can stagger the seams. I wouldn't bet the farm on all these wood free boats. Until you see one that beat the sea for 30 years and is still holding up, I will take a properly made fg and wood. A lot of your custom high dollar yacht builder still use wood and epoxy. If the boat builders would use more epoxy on the wood structure parts you wouldn't see near as many problems. Most problems occure when the cut holes in the stringers and bulkheads and don't seal them up. That goes for the floor also.	2002-05-28
Franki	Hi guys, I wrote to these guys and asked if it would bond to glass well.. I got a pretty straight answer.. NO! It also expands alittle to much for marine uses.. (it expands with heat, not water.) just thought you guys should all know. rgds Frank	2002-05-30
outonbizniz	Frank is that KingStarBoard of Polyboard you are talking about?	2002-05-30
Franki	This stuff... http://www.renewresources.com/polyboard.html I emailed them and asked if it would bond to fiberglass.. he wrote back and said "not very well" doesn't mean you can't use it.. just means you can't glass it in... I'd probably keep looking though.. I think you should use wood.. its only the floor.. I don't like wood stringers or transom.. but the floor is not really a structural member.. and its raised up.. so less effect of rot damage to a degree.. and easier to replace then stringers/transom.. in your position I'd look around for an alternative alittle longer, then settle for ply if I didn't find any.. (maybe you should find a "non wood" boat manufacturer and email them regarding what they use.. (pretend you are a potential client.) they will tell you all manner of stuff...) rgds Frank	2002-05-30
dhammann	What about pressure treated plywood? About $25 for a 4x8 sheet at Lowes. No need for sealing with resin or epoxy....Just a thought.	2002-05-31
epresutti	Like hawkeye1 I just glassed in the deck (after lot's of other stuff but that's another story). Multiple layers of wood with a layer of glass is much stronger than a single layer of wood with glass. I did some research, used the West Systems "FiberGlass Boat Repair and Mantenance" in addition to "The Fiberglass Manual" by Keith Noakes, not to mention advice from this forum. I was warned away from pressure treated wood (didn't try it), but apparently it has a high moisture content and will rot from the inside if encased in glass. I used two layer of 3/8ths with glass on both sides and in between each layer. Using marine grade seemed to be an interesting question. The important thing I learned (from this forum and other sources) was that the plywood must be free of voids. Luan (1/4") or plywood designed for tile floors that have no voids seem to be the same as marine grade (my oppinion). I put together some samples to check and you can beat them REALLY hard with a hammer and still not break through. Additionally, I used epoxy resin. I will be posting on my WEB site the entire project AFTER I am in the water. Hope this helps, Cheers. emp.	2002-06-01

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