Poly. or Epoxy Resin for Floor Project?

[pmgrape]

I am gathering info for the future reflooring of my 19' Renken bowrider (1988).<br />I feel I have a pretty good knowledge base for tackeling this project. My only lingering question is which resin would be better polyester or epoxy?<br />I have heard that polyester doesn't offer complete moisture protection for the coated plywood, but is fairly inexpensive and allows the use of mat which is easier to work with. On the otherhand, I've read epoxy resin provides much better moisture protection, is harder to work with, and more expensive.<br />I want a new deck that will last for a good 8-10 years. <br />Any input as to the differences between these resins and which would be best for a novice working with glass would be extremely helpful. I have posted here several times (all with good results) and value any and all comments.<br />Thanks<br />Brian

 

[Captain12pk]

Re: Poly. or Epoxy Resin for Floor Project?

Hey Brian,<br /> I work with polyester resin every day. It is fairly easy to work with. Coats well and works with mat well. It should be just fine to use for the floor. Most boat companys use that to begin with. At least the two I have worked for have. Might I also suggest another solution/option? There are composites out there that gauranteed never to rot. It is more expensive, but in the long run you have piece of mind knowing you never have to worry about reflooring that boat again. That material is as thick as a regular piece of plywood too.

 

[bartborchardt]

Re: Poly. or Epoxy Resin for Floor Project?

I would go with epoxy. I don't think it's any harder to work with and it will last a lot longer. What is better in the long run, redoing the floor in about 5 years or having it last 10. I have used both and would go with epoxy.

 

[Captain12pk]

Re: Poly. or Epoxy Resin for Floor Project?

One thing to think of in either case of a wood floor replacement. I know for a fact that when I worked for Stratos, only one side of the floor was matted. Both sides were coated in resin, but with water in the hull, moisture could easily soak thtrough the resin and penetrate the floor from the bottom. I would put a layer of mat on either side of the floor. Or you could go with compisite floor. Comes in sheets like plywood and can be cut pretty much the same way. I think it runs like $20 sqft. though.

 

[crab bait]

Re: Poly. or Epoxy Resin for Floor Project?

please explain CAPT 12PK.. clear me up..<br /><br />what your sayin' is that resin alone won't stop moisture but addin' 'mat' will..??<br /><br />BRAIN... if'n its worth doin',,, it worth doin' right...

 

[JasonB]

Re: Poly. or Epoxy Resin for Floor Project?

I used poly, but epoxy would last longer.

 

[Hawkeye1]

Re: Poly. or Epoxy Resin for Floor Project?

I think poly is harder to work with because of the fumes and kick times. Epoxy doesn't fume near as bad, sticks like nothing else on earth and is not as tempeture senitive as poly is.

 

[b.gagnon]

Re: Poly. or Epoxy Resin for Floor Project?

I just finished installing a floor in a 15ft alum.. And I used West Systems epoxy. It was very easy to apply and came out way better than I thought it would. The only downfall is the price; it was about $100 per gal with the hardener. I used one whole gallon with two coats. If I had to do it all over again I would go with the epoxy. It is a lot of work to do a floor so you might as well make it worth it!

 

[JasonJ]

Re: Poly. or Epoxy Resin for Floor Project?

If your bank account can handle the shock, epoxy is the better bet. I am almost done with the floor replacement phase of my project, and I have been using poly. I have had to use a respirator the whole time, and my project is held up every time the temps are below 60 degrees. I don't regret using poly becuase it works fine, but I have used 7 gallons so far, and will have used at least 9 gallons by the time I am done. Epoxy would have killed my budget. If you are looking for a material that will allow you to leave the boat out in the rain and not keep it covered, you might as well scrap the whole project and get a 14 ft aluminum jon boat. As long as you are using wood in a boat, you have to take care of the boat. I cannot emphasize this enough. It isn't that fact that a boat was made of poly that causes it to rot. It was the owner that left it in the rain and snow that allowed it to rot. I have seen too many well taken care of boats that are in near perfect condition just because the owner had the foresight to park it under cover and make sure all its hardware was sealed well.<br /><br />You can use poly and your project will turn out fine as long as you can deal with the stink. Epoxy won't give you some secret amazing wood preserving advantage, water will find a way to ruin the wood. In the end its up to your wallet, but you still have to take care of the boat after you finish the project, or you'll be right back to where you started despite what you use. Good luck....

 

[Captain12pk]

Re: Poly. or Epoxy Resin for Floor Project?

Using resin only on the floor, CRAB, does not alow for flex. Wood flexes and a boat needs to do so. The resin, either epoxy or poly, does not flex by itself. It would crack allowing areas for moisture to seap into the wood. A layer of 1/4 oz. mat layered over the surface mixed in either resin, lightly, will absorb and seal while conforming to the wood throuhout any flexible wake twisting or busting process. I have learned that the thinner the resin is better. Besides lighter weight, it also has more give than a thick coat of resin that would crack or flake. Thicker doesn't mean stronger. I have been manufacturing boats for almost 10 years. That is one of the things I have learned in that time.

 

[BillP]

Re: Poly. or Epoxy Resin for Floor Project?

There are a lot of variables to consider and both poly or epoxy will do the job. The longer I use epoxy the less I like it though. <br /><br />In my experience, epoxy is more difficult to work with than poly in big temperature changes...like today, 70F at 8am and 90F at noon. The kick time goes from 30 minutes to 5-7 minutes. You have to buy slow, med or fast kick resin and deal with kick times that way. This means different resin for same day work (what a hassle). For laminating big areas this can be tough to manage, especially when doing multiple layers. If you use slow kick for for low temps the resin can (does, will, been there and done it) run off vertical surfaces and puddle (leaving a dry and weak lamination). Epoxy has to be mixed per ratio but you CAN speed up the kick by adding heat only. Epoxy requires sanding between coats once hard. Contrary to posts I keep seeing, there IS mat available for epoxy resin. I use it and it wets just like poly mat. Epoxy is easy to work in small batches but glassing large areas can be a rush in hot weather. Again, strickly my own experience speaking here.<br /><br />Epoxy is much more flexible than than poly for coating...I've coated (40-60 mils thick)wood boat hulls up to 42' without glass and had the coating stick way beyond 10yrs without signs of peeling. Epoxy will gap fill and poly NO way. This is a clear advantage for epoxy (expecially on stringer and floor projects where fit is tough). Poly can be thinned and coaxed to work but it still is no match. I coated plywood boat hatches with poly res and had ok results but the surface was still brittle and dinged easy. For coating the underside of floors, poly should have mat for flexibility and epoxy only needs mat for damage control. <br /><br />For poly...you can match the hardner to temp and humidity to meet the desired work time. I've worked with poly resin down into the 40sF and up to the high 90sF. Very workable in situations where you are laminating a large area and need time to work. You can also hot coat or add heat to poly to push a slow cure. Using poly "laminating" resin eliminates sanding between layers...this doesn't happen with epoxy.<br /><br />I do epoxy mainly where superior tenacity, gap filling and ability to work with moisture are needed...none are good attributes of poly res. Strengh isn't a factor as I can bulk up poly to get that.

 

[mercuryblues]

Re: Poly. or Epoxy Resin for Floor Project?

I work with poly resin on a daily basis and I will tell you this, resin alone or even with mat is not waterproof,in fact it will draw water like a wick.You have to rough up the surface of resin/fiberglass with say 40 grit sandpaper then paint it with gel coat.Then your fiberglass is water proof just like a swimming pool.Hope this helps you.

 

[crab bait]

Re: Poly. or Epoxy Resin for Floor Project?

what BILLLP said is true.. but in this case they're a couple truths..<br /><br />the epoxy i use from CLARK-CRAFT.com is a 1 to 1 mix... there is no need to sand between coats as with higher ratio epoxies..<br /><br />also,, with this epoxy ... there's only one hardener... there's no 'fast or slow'.. it is what it is..<br /><br />in 75 deg f. you'll get 1/2 hour of 'playtime'for sure.. <br /><br />it don't like like past 60deg f.<br /><br />in heat,, always seem like i get to the 'cloth skin fiberglassin' in july an august,, 90 to 95 deg f an super humidity.. <br /><br />you just hafta be smarter then the epoxy .. <br /><br />i store it in the house with a/c.. take it outside in a cooler with a few ice packs.. <br /><br />do my do ,, an still have a 1/2 hour 'playtime'for sure.. which ain't bad..!!<br /><br />but some of the biggest advantages of epoxy is that it is a glue an bonds to wood.. opposed to poly ,,which is not a glue ,, an truley does not bond to wood over time.. <br /><br />an that poly does nothin' for rot protection .. lets rot causin' water moluclues pass right on thru it..<br /><br />not sayin' that poly is a bad thing .. it just shouldn't be used on wood.. <br /><br />but there is one good advantage of polyester resin... IT'S CHEAP...

 

[BillP]

Re: Poly. or Epoxy Resin for Floor Project?

Hey Crab...does the clark craft epoxy stay sticky for days after it is cured...or are you talking about non-blushing epoxy?

 

[crab bait]

Re: Poly. or Epoxy Resin for Floor Project?

no it hardens rite up.. it's the most flexiable poxy i ever seen... has no brittle in its D N A...<br /><br />has no sign of amine blush.. <br /><br />it's a good price ,too... <br /><br />one neet thing is if'n your buildin' a boat.. <br /><br />( they also sell boat plans & even boat kits... they also sell 'boat encapsulation/fiberglass kits for all their boats..) <br /><br />well i always buy a kit for one of their boats ,, thats somewhat bigger that my boat.. <br /><br />so i get more than enuff stuff to do my boat .. except epoxy.. their 'kits' max out at 6 gallons.. so if you need more,, you have to buy it...