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82SleekCraft
07-20-2006, 10:36 PM
Searched but didn't find anything to here goes.
The time has come for me to have to replace my wooden carpeted floor on my 21-footer. Before I go down the usual route of using plywood, I was just wondering if anyone had tried an alternative. Fiberglass is the first thing that comes to mind. After all, a lot of new deck boats use fiberglass floors. Anyone got any ideas, suggestions, pictures?
Thanks in advance.

2dasand
07-24-2006, 06:08 AM
Even to do a fiberglass floor, you will need something to form to. Obviously, you cannot make a mold of the floor, and make it out of the boat very easily, so you would probably still have to use some sort of wood, and the glass over it, I would imagine.

DUCKY
07-28-2006, 08:10 AM
Don't bother. The plywood in your Sleek probably wasn't resin coated on the bottom and then it was covered in 'glass on top. Excellent recipe for rot. When you make your new floor, use QUALITY Plywood (the stuff that's plugged and sanded on both sides, no knots 7 or 9 ply 3/4") and before you install it, resin it on the bottom several times and use surfacing agent in the final coat (it's repels water) then when you install it, just tab it in with 8-12" wide strips of mat and 1708 woven composite. Then sand off the burrs and repeat the flow coat process. What you will end up with is plywood encapsulated in resin with a wax barrier. It will probably outlast your boat

Classic Daycruiser
07-29-2006, 01:35 PM
Don't bother. The plywood in your Sleek probably wasn't resin coated on the bottom and then it was covered in 'glass on top. Excellent recipe for rot. When you make your new floor, use QUALITY Plywood (the stuff that's plugged and sanded on both sides, no knots 7 or 9 ply 3/4") and before you install it, resin it on the bottom several times and use surfacing agent in the final coat (it's repels water) then when you install it, just tab it in with 8-12" wide strips of mat and 1708 woven composite. Then sand off the burrs and repeat the flow coat process. What you will end up with is plywood encapsulated in resin with a wax barrier. It will probably outlast your boat
I agree with Ducky. Use plywood. 3/4 inch is not necessary, remember weight effects boat speed. The wood floor is part of the boats structure, but 5/8" plywood is plenty for your 21 footer, just coat both sides with 3 coats of resin. You don't need the best plywood, since your covering it in resin and carpet??? If your fuel tank is under the floor, it might be a good time to pull it out and clean it.
Good luck...about a 40 hour job.
Chance's are you interior is rotten. Be sure to match it up to the original interior for the classic look of a sleekcraft. I just went through the whole floor and interior replacement. The floor is the easy part of the job.

jimslade
08-16-2006, 04:06 PM
Nidacore-3/4 inch two layers of 1810 glass. very light and will never rot.

martan
11-05-2006, 05:26 PM
Coating a piece of plywood with resin will do nothing to prevent rot. Plywood will expand and shrink and resin alone will simply crack the same way that gel coat does. You can make fiberglass panels using a flat stock table. It's going to cost a lot more in materials and also more time. Also you will need to add a lot of mini bulkheads because the fiberglass will not span an area as big as a 5/8 piece of plywood will.
www.bowkersfiberglass.com

DUCKY
11-05-2006, 09:30 PM
Coating a piece of plywood with resin will do nothing to prevent rot....
Are you nuts? Why don't you take two pieces of wood, seal one with resin/surfacing agent, and leave one bare. Throw them outside and say that again in about 6 mos.
Now then, I am not going to argue the point that there are not better materials out there if you are simply trying to prevent rot in a new boat, because there are. Your idea of making preformed panels is a reasonable one, as is "Slade"'s nidacore, but properly treated quality plywood is simply the best "bang for the buck" from a repair situation. This guys boat lasted over 20 years with a plywood floor that probably wasn't even sealed up worth a damn (knowing his vintage of SleekCraft pretty well). I don't mean to come off harsh here, because I am really a pretty agreeable guy, but incorrect statements like the quote above don't do any good for anyone.

DUCKY
11-05-2006, 09:35 PM
Searched but didn't find anything to here goes.
The time has come for me to have to replace my wooden carpeted floor on my 21-footer. Before I go down the usual route of using plywood, I was just wondering if anyone had tried an alternative. Fiberglass is the first thing that comes to mind. After all, a lot of new deck boats use fiberglass floors. Anyone got any ideas, suggestions, pictures?
Thanks in advance.
If you were to cut through the fiberglass floor on many of the new deckboats you are referring to you will most likely find plywood under the glass and gelcoat, covered by more fiberglass on the back side, especially if it is one built here on the west coast. There are a few companies using the nidacore and similar materials, and if I were building new boats I probably would as well. The main problem with the honeycomb materials (for floors, stringers, or transoms) is trying to fasten anything to it. If you through bolt, you will crush it and you can't run screws into it as they will just pull out. There is a drag boat that I work on that has honeycomb aluminum stringers covered with carbon fiber. To mount the motor cage, they had to make interlocking aluminum bushings that go all the way through and have a .060" crush limit built in, so they could actually tighten the bolts without destoying the stringers.

martan
11-12-2006, 05:58 PM
Are you nuts? Why don't you take two pieces of wood, seal one with resin/surfacing agent, and leave one bare. Throw them outside and say that again in about 6 mos.
Now then, I am not going to argue the point that there are not better materials out there if you are simply trying to prevent rot in a new boat, because there are. Your idea of making preformed panels is a reasonable one, as is "Slade"'s nidacore, but properly treated quality plywood is simply the best "bang for the buck" from a repair situation. This guys boat lasted over 20 years with a plywood floor that probably wasn't even sealed up worth a damn (knowing his vintage of SleekCraft pretty well). I don't mean to come off harsh here, because I am really a pretty agreeable guy, but incorrect statements like the quote above don't do any good for anyone.
I guess being in the repair business since the late 80s and replacing transoms and stringers and floors on boats as new as only 5 years old makes me a little nuts. I see boats more than 40 years old with the original wood still intact and ya know why? Way back then they only tabbed wood into place. The wood is allowed to breath and water does not get trapped. Are you really trying to say that coating a piece of wood with resin makes it water proof? If it doesn't make it water proof then what does it do? Wood will draw moisture in if it is able and resin won't stop this from happening. What resin will do is stop the wood from being able to dry out. I've been doing it long enough to know what works and what doesn't. If you're going to put anything on the wood it better be able to completely seal it or it's going to cause it to rot.
www.bowkersfiberglass.com

DUCKY
11-12-2006, 08:12 PM
I'm done here...
Although I do understand your train of thought, it just doesn't work in the real world, and arguing on the internet is like running in the special olympics....
Have a nice day!

ThongMagnet
11-13-2006, 12:42 PM
My original wood floor lasted 21 years until it started to "Dry" Rot. I used cheap plywood 5/8" thick and a lot of resin before and after floor installation. I don't think it will rot again for 20 years +.
Car interiors rot, and they are made of plastic resins which dry out. Corvettes are made of fiberglass, and they crack and dry out. Wood is your best bet for your boat, and don't let some guy tell you he has been doing this since the late 80's, and he has a better way of doing it. That is BS.

Cheap Thrills
11-13-2006, 01:56 PM
Funny, I didnt see anything in the original request pertaining to Attitudes or a Pissing Match. " Ideas, Suggestions, Pictures"
I have a great Idea, Why dont we try to get along.
Working together to solve a problem always works better than fighting about it.
Great Minds Discuss Ideas,
Shallow Minds waste entirely too much time bickering about the Ideas.
C.T.

lucky
11-13-2006, 02:20 PM
I'm done here...
Although I do understand your train of thought, it just doesn't work in the real world, and arguing on the internet is like running in the special olympics....
Have a nice day!
Ducky - I believe you , as your sigy line clearly has more information and and includes the words v drive lmao -- besides Barney rules :)

jimslade
11-13-2006, 07:31 PM
Wood is old tech. Core materials are the future. Light and no rot. Wood is only for above the waterline. After you have replaced rotten wood in a transom, core materials are peace of mind.

Kim Hanson
11-17-2006, 08:52 PM
Funny, I didnt see anything in the original request pertaining to Attitudes or a Pissing Match. " Ideas, Suggestions, Pictures"
I have a great Idea, Why dont we try to get along.
Working together to solve a problem always works better than fighting about it.
Great Minds Discuss Ideas,
Shallow Minds waste entirely too much time bickering about the Ideas.
C.T.
Now what fun would that be.........( . )( . )............

Kim Hanson
11-17-2006, 08:53 PM
Ducky - I believe you , as your sigy line clearly has more information and and includes the words v drive lmao -- besides Barney rules :)
That was funny..........( . )( . )................

Tom Brown
11-19-2006, 02:34 PM
If you were to cut through the fiberglass floor on many of the new deckboats you are referring to you will most likely find plywood under the glass and gelcoat, covered by more fiberglass on the back side, especially if it is one built here on the west coast. There are a few companies using the nidacore and similar materials, and if I were building new boats I probably would as well. The main problem with the honeycomb materials (for floors, stringers, or transoms) is trying to fasten anything to it. If you through bolt, you will crush it and you can't run screws into it as they will just pull out. There is a drag boat that I work on that has honeycomb aluminum stringers covered with carbon fiber. To mount the motor cage, they had to make interlocking aluminum bushings that go all the way through and have a .060" crush limit built in, so they could actually tighten the bolts without destoying the stringers.
I will back up this post. Leaving the bottom of the wood open is the only way to go but that's only half the job. The other half is keeping the moisture out of the sub-floor and that means taking the foam out. Don't re-foam. People put pool noodles and all kinds of crap in there but that stuff just traps moisture and rots the wood.
How long can you expect a piece of plywood to last when it's got a wet sponge touching it?
I leave my floors open underneath, move the drain holes to the bottom of the bilge well, so the holes are semi-circles that come up from the bottom of the hull. That way, there is nothing impeding the water as it flows back toward the drain plug. As a final measure, I installed a couple of small 12v box fans (computer style) up under the dash to blow air into the sub-floor. That keeps it nice and dry.
I've pulled apart quite a few old Glastrons and the floors are always OK, except where they were penetrated by rigging. The rot is always around the screws. Bad rigging is the death of boats. Anywhere you drill or screw, you have to seal. Silicone doesn't work. Use LifeCalk or equivalent polysulfide sealant.

InKahntrol
11-20-2006, 09:22 AM
When we redid the floors of my Campbell, we made them out of diamond plate aluminum. It actually weighed less on the scale than marine plywood, it's stronger, it will never rot, and when you pull the carpet up (I installed mine with snaps) it looks really sweet. Of course it's hot in direct sunlight, hence the carpet.

jimslade
11-21-2006, 04:55 PM
Aluminum will rot(powder) when exposed to water.

martan
11-30-2006, 05:59 AM
I just recieve some samples from coosa composites. Has anyone ever used this stuff before? The adhesion is excellent and it seems to be a bit lighter than wood. I am looking into using this for upholstery such as in an engine hatch or seat boxes. It would just be so much easier than having to glass over everything and glue doesn't stick good to treated plywood. I am waiting to see how much a sheet of this stuff costs. I am hoping its cheaper than plastic board.
www.bowkersfiberglass.com

bwillieb
11-30-2006, 08:25 PM
................multi laminate plywood (8 or 9 ply construction grade) is cheap at Home Depot.........cut your floor........brush on three coats of 'West Systems' Epoxy,......making sure to do the end grain and the grain inside any holes.......Google... Gougeon Brothers or West Systems,..for the trick way to attach your floor.......check your stringers closely for any signs of rot...........West Systems has been the salvation of wood problems in big boats for years.........If you know someone with port supply discount at 'West Marine' stores........your material cost will be greatly reduced..........Epoxy sticks to polyester resin(fiberglass)but not visa/ versa.......sounds like composites are the wave of the future?............

sorry dog
12-03-2006, 08:31 AM
I will back up this post. Leaving the bottom of the wood open is the only way to go but that's only half the job. The other half is keeping the moisture out of the sub-floor and that means taking the foam out. Don't re-foam. People put pool noodles and all kinds of crap in there but that stuff just traps moisture and rots the wood.
How long can you expect a piece of plywood to last when it's got a wet sponge touching it?
I heard that PVC is the way to go for extra flotation material that lightens the boat.
BTW - I always take Ducky's advice. He makes some of the best drain plug designs in the world.

martan
12-09-2006, 08:16 AM
I don't think resins will stick to PVC board. It's also exspensive and when I tried some I didn't think it was all that light.
www.bowkersfiberglass.com

axkiker
12-12-2006, 05:38 AM
Why not go with a marine grade playwood. The stuff is guaranteed to not rot for like 30 years even in the water. Might be a little heavier but we are not talking about a crazy amount of weight on a 21 foot boat. Maybe an extra 25 lbs .

Towndrunk
12-14-2006, 07:30 AM
Just take the plywood out and turn it over. Be sure to oil the rotted side with penz 10w30.:cool: Should be good for another 20 years.:D

Kurtis500
12-16-2006, 03:47 PM
Depends on what you want to spend. You can get a good 3/4 inch aramid core and glass it on both sides. Closed cell core is what you would want. It may be a little tricky if you've never done it. Most of the time this kind of construction is vacuume bagged, but you can hand lay if you do it right. Most floor panels in aircraft are constructed with aramid cores and thermoplastics/thermosets. Or, for cheaper and easier, just glass over your plywood.

Kurtis500
12-16-2006, 03:49 PM
I just recieve some samples from coosa composites. Has anyone ever used this stuff before? The adhesion is excellent and it seems to be a bit lighter than wood. I am looking into using this for upholstery such as in an engine hatch or seat boxes. It would just be so much easier than having to glass over everything and glue doesn't stick good to treated plywood. I am waiting to see how much a sheet of this stuff costs. I am hoping its cheaper than plastic board.
www.bowkersfiberglass.com
Yes I have used products from them. What product do you have? If its a coring material it wont be cheaper than a plastic sheet.