Question for epoxy users

[Arne]

A single coat of epoxy should give ample protection for you. The additonal coats are to give a smooth finish. If you sand it down to smooth it, you will reopen some wood pores. And then you need an additional coat.

For the weekend, I think you are fine.

[Nitetimes]

About the weight of your trailer.... seems about 150 pounds too heavy... If it really weighs 400 pounds, I hope that is with the suspension and not just the frame.

And your wheel placement is determined by balance point, not by where you think it looks good.

Weight should be around 400 with suspension, wheels, tires and deck so that's not too bad. Might weigh it today before I put the walls up.
I have a pretty good idea how the wheel placement works after 15 years designing and building trailers so I'm gonna say it will be pretty well balanced when it's done.

[angib]

I haven't seen anyone mention it here, so you should note that as epoxy resin cures, a waxy layer of amines collect on the surface - the technical term is 'amine blush' which sounds kinda sweet!

One feature of this amine blush is that it stops anything else from sticking properly to the epoxy underneath and so it has to be removed if you want a good bond. In theory washing with soap, water and a Scotchbrite pad will remove the amines, but it's rare to find an epoxy user that trusts this method - the only real guarantee for a good bond is rubbing down with sandpaper.

The only exception to this is if you are applying epoxy 'wet on wet', before the first layer of epoxy has gelled much. My test is that if I put my finger on the epoxy and it gets wet (ie, some epoxy comes off on my finger), it's OK to overcoat without sanding.

I should add one more exception - if you know you want to bond something onto epoxy later, you can can cover it when wet with a 'peel ply' - a layer of woven nylon material. After the epoxy has cured, the peel ply is 'peeled' off (this can be hard work!) taking the amine blush surface with it.

Andrew

[asianflava]

I should add one more exception - if you know you want to bond something onto epoxy later, you can can cover it when wet with a 'peel ply' - a layer of woven nylon material. After the epoxy has cured, the peel ply is 'peeled' off (this can be hard work!) taking the amine blush surface with it.

Andrew

Thanks for the info, I thought the peel ply was to give it a rough surface to give it more "tooth".

[angib]

Thanks for the info, I thought the peel ply was to give it a rough surface to give it more "tooth".

Nope, though it can't harm. Pulling off peel ply is snapping the little columns of resin that rise up between the warp and the weft fibres of the peel ply. (There is no need to know that, but knowledge never hurts....)

I wanted to make sure everyone understands that peel ply is pretty special stuff - well, pretty simple but specialised. Do not be tempted to try to use any other material as peel ply because it won't come off!

Andrew

[mbader]

I took my unfinished tear on a week long trip from Calif. to Colorado.
I had 1 coat of epoxy sealer(Smiths A and B) on the wood. It rained nearly every day and there was no damage to the wood.

[SteveH]

I took my unfinished tear on a week long trip from Calif. to Colorado.
I had 1 coat of epoxy sealer(Smiths A and B) on the wood. It rained nearly every day and there was no damage to the wood.

Malcolm,

You can't just tell us something like this without any pictures. We want to see PICTURES.

[doug hodder]

Anjib writes about an amine blush....he is correct...as I understand it, the amine blush is caused by humidity conditions....I know of boat builders that have had problems with it....I can't help anyone out on this one as I build a fire in the garage and cure it all with a dry heat...and I live in a dry environment...high humidity will cause a cloudy appearance in the cured epoxy....I've built several boats and have never had an amine blush problem...It turns a dull/ cloudy appearance...I would think that you could scuff it off with a 3M scotchbrite pad and then sand the epoxy to give it a tooth for the next coat....You need to scuff sand between coats anyway....Epoxy will not chemically bond to the previous layer ....On a boat...I do about 5 coats on the hull and 6-7 on the top deck, sanded down inbetween layers to fill any gaps, take care of bubbles coming out of the wood....At any rate...the first coat seals up the wood, any fine finish is going to require more layers of material laid down...Lay it down with a roller...then top it off with backdragging a roller cut in half held in a spring clamp, to knock down the high spots and give a more finished surface...I'm by no means an epoxy Guru....but this is what has worked for me, and what I learned....Doug

[Juneaudave]

Maybe I can help a bit with epoxy... first off...there are a lot of different types of epoxy that you can use..either with cloth or as a sealer over wood. You really need to get the right epoxy for the application. Most manufacturer's websites can direct you to the right resin and hardener depending on your application and working conditions, humidity and temps. Don't be hesitant about calling their technical reps.

I predominantly use the clear coats for boat work. All the major brands are good and have advantages and disadvantages. I personally like West 105/207, System 3 with the slow hardener, and Raka. They are spendy, with a gallon running close to $100 all said and done, but you have to look at the application...most boats are subjected to a harsh environment, and if you are just sealing wood that is to be covered, I think you can get by with much cheaper.

With epoxy... a single coat does not seal the wood. It will still breath and tranfer water. Two or three coats will seal the wood...and in general...three coats properly applied will provide a good base for varnish or paint. This is really important...epoxy has to be covered, painted or varnished with a good UV resistant spar to prevent degradation.

When appling epoxy, you do need to put the second and third coats on prior to the previous coat completely curing. Epoxy will form a chemical bond to the previous coat if you follow the manufacture's instructions. If you can't get at it, you may need to sand with a 120 grit to get a good mechanical bond...and depending on the epoxy...maybe even wash off the "blush" caused by some epoxies. From my experience, blush is a function of the epoxy type, not humidity. Many good epoxies can be applied in cool and humid conditions without any concern for blush.

[Roly Nelson]

Oh boy am I confused. I guess my question is simply, can I use an epoxy to seal the end-grain of my wooden doors and hatch lid edges, and then simply paint them? When doing some boat-work some years ago, I coated some wood with 2 part epoxy, and it seems to have sealed the wood grain very nicely. Seemed nice and shiney plus it was waterproof.

All I want to do, is to seal many exposed edges of doors, windows, hatch lid and so on, mainly to keep out the water. I just want to keep it cheap, slop on some inexpensive paint and hopefully, end up with a tear that won't delaminate in the first rainstorm. I guess in my uninformed carpenter-like training, I seem to think that if exposed edges of glued together pine and plywood, are coated with epoxy, no water will penitrate and the results will be sucessful.

Am I on the right track, or would I be making a big mistake by coating these members, with a 2 part epoxy material?

Will paint stick to this stuff, so that I won't have to be doing some repair work because I failed to understand the compatibility of the 2 products? Help me out here, I am patient and will await any logical info.

Roly.............. cautioning anyone, that whenever you roll your tear over on it's top, in order to coat the bottom with roofing pitch, be sure to sweep the workshop floor absolutely clean, or else any little obstruction will punch a hole in the 1/8" roof plywod.

Duh, now I have had to glue a "dumb, hole-in-the-roof concealer", with a hand-carved mustache block of wood on the inside, to hide my mistakes. I learned many years ago, that we woodworkers often screw up, but eventually you just have to learn how to cover up these errors, so no one is the wiser. Has anyone been there, done that?

[bledsoe3]

Has anyone been there, done that?

Nope, not me.

Well, not that I'll admit to.

[asianflava]

This morning, I went out to look at the tear. The epoxy I applied looks like it was soaked in by the wood. The wood still had a dull wet look to it. I ended up scuffing the trailer again and applying another coat. This time it looks nice and sealed. I tried what Doug had suggested. I rolled it on then tipped it off with a foam brush. It looks much better, maybe the next one will be a woody?

[mikeschn]

Len,

How did you prepare the wood under your green paint so that the woodgrain didn't show through?

Mike...

[len19070]

Actually Mike My roof on the Slumber Coach, and on all my trailers is Pre painted Aluminum. It can be gotten through anyone's local "Sign Shop" that does outdoor metal signs. White 32 ga. is about $45.00 for a 4X10, other colors are more because they are thicker i.e. 40-50 ga. But I get it in bulk from a company called "Wrisco" They are suppliers of aluminum sheets for the Sign industry

http://www.wrisco.com/

Happy Trails

Len

[Arne]

The first coat of almost anything will raise the grain. Once the first coat hardens, that will not happen again, after lightly sanding the first coat, the next will fill and if a 3rd is applied, it will get smoother. Tipping, as you mentioned, gets rid of the bubbles and drags off the lifts left if applied with a roller. On the uniflex 255, it gets rid of the dimple effect Mike got on his, and I got on my first go round.

My kayaks have 3 coats, the first 2 applied with a squeege. The first sticks the cloth, the second fills most of the grain, and the 3rd applied with a roller finishes it off... then prime and paint.

On rollers, I find I get the best rest results with a 1/4" nap roller from h/d. I've also started cutting them in half (to get two 4.5 inch pieces) and using shorter rollers. The short nap lifts the coating less, and the short length allows better working on the many rounded surfaces on a tear.