CPES

[Boanerges4]

Ive been trying to do my homework on CPES. I know its agood product but is there any other way to seal your trailer? I would like to keep the sides a natural wood with some type of metal roof. Someone please sound off I need help. Thanks Dennis

[dh]

I'm not a fan of CPES. It is just thinned down epoxy, when the thinner evaporates, you are left with voids in the coating. West system's 205 resin (standard issue) with 207 hardener (special) would be my choice for a natural wood finish. The 207 is specifically designed for a nice clear finish on natural wood. It still needs a coat of varnish for UV protection.

[aggie79]

As DH said, the CPES is not sufficient enough by itself to seal the wood. You will need to coat with epoxy and some type of UV resistant coating also.

I used both CPES and epoxy on my teardrop on the exterior of the floor, sidewalls, hatch, and roof. The only exposed wood on my teardrop is the tongue box. It was built using cedar tongue and groove boards over a plywood frame. On it, I did not use CPES, but used used Raka-brand epoxy - 3 coats, followed by 3 coats of (brushed on) of Emtech EM 9300 by Target Coatings.



Take care,
Tom

[madjack]

...what they said...both of 'em.................................................................

[dh]

I can't speak for RAKA, or other brands for that mater, cause West System is what I can get locally. But, West System studied the effects of thinning thier epoxies and published thier results. I'll spare you details and get to my point. They say, in wrighting, that thinning thier epoxy with acetone or lacquor thinner will yield a prduct 'very similar' to CPES type products. If you go the CPES/epoxy rout this could save you from dealing with different materials.

[LDK]

I used cpes on my build but I'm also skinning with aluminum too. I was more concerned with my plywood end grain and cpes is an excellent choice for that. It really sucks it in on the end grain.

[schaney]

The solvents in CPES help dry out the wood and pull the epoxy into the pores of the wood. So it penetrates deeper into the wood than a full bodied epoxy like West Systems can. I use it as a grain filler / sealer, then top coat with Target Coatings EM2000 waterbrone alkyd varnish. I find the EM2000 more brush friendly than the EM9300.

[dh]

So, you have epoxy, with voids in it, deep into the grain of the wood. Please explain how this seals out moisture. Personally, I'll take an epoxy coating on top of the wood before one in the wood. Is the paint on your car in the metal or on it? The epoxy does its job by being a solid surface (no voids) on top of the wood, blocking out moisture. It just needs to pentrate enough to key into the wood.

[madjack]

...if you use CPES, you should use three coats minimum to fill the voids left by the volatiles gassing off...this actually applies to most all sealers, including epoxy...the advantage of epoxy, is it leaves a "plastic" encapsulation to the wood...of course, this coating can crack as well as needing to be protected from the dreaded UVie's...there are tradeoffs to whatever you use and as long as you use it for it's intended purpose and according to manufacturers directions(or what WE tell ya), you should be good to go!!!!!!!
madjack

[DudKC]

Would the West system 205/207 with several coats of spar urethane be good?

[Tumbleweed_Tex]

Has anyone ever tried one of the log home finishes on their trailer? Seems to me if it would protect a house, it would do the same for a tiny trailer.

http://www.logfinish.com/store/exteriorfinishes.php

[dh]

Would the West system 205/207 with several coats of spar urethane be good?

Been proven on boats. Gougeon brothers, makers of west system, is a boat building outfit.


The 207 has a UV inhibitor in it, but still needs a ''high quality UV filtering varnish''.

[dh]

Oh, if you go with WS, I'd read the user manual first, and if you have to order your epoxy, get the mini pumps at the same time. They make metering the epoxy simple cause the pumps are calibrated, so one pump of resin to one pump hardener. Best $15 I ever spent.

[schaney]

DH, as Madjack noted, it takes a couple of coats. Okoume/Meranti needs 2 coats, birch / pine / fir needs 3 coats. Also yes, on everything else Madjack said.

It's worth noting that my approach to finishing a rolling "plywood box" is based on storing it out of the weather. Grain filling and 3-5 coats of a good exterior clear finish work fine. For ones stored outdoors, I take more of a boat building approach. Marine grade plywood, 6-8 oz fiberglass cloth, 3-4 layers of West Systems epoxy (207 hardner) to completely fill weave and finally top coated with 3-6 layers of clear marine varnish.

Yes, with West Systems, get the mini-pumps.

[dh]

I tend to forget some have the luxury of free garage space. I make about 1/4 of my income out of my garage, so storing anything there that takes up floor space is out of the question.