A couple of epoxy questions

[Nosty]

Hi All,

I was curious as to whether you need to use a specific wood filler for nail, screw and staple holes before you apply the epoxy? Will the epoxy adhere to, say, Elmer's exterior wood filler or will there be an adverse chemical reaction? Is there a product anyone has used for filling holes that worked especially well with the epoxy?

Also, I scoured the paint roller shelves at HD yesterday looking for a foam roller that would be compatable with the epoxy. They said either paint or stain. Some went as far as to say oil or water based, but I didn't see any that said they wouldn't break down with anything other than the paints they're intended for.

Lastly, what's the best type of pail to use to mix the epoxy? Is a metal type can best, or are their plastic pails that will work? Would it be wise to mix it in a metal paint roller tray and then just work out of that tray?

Sorry about all the questions, but I'm planning on getting started this week and I'm making that eleventh hour dash for what little information I haven't been able to glom from the old posts.

As always, thanks for all your help.

Brian

[Arne]

Epoxy will stick to almost anything that it can grip... meaning, it is sanded and has good purchase. any wood filler is fine.

I never use foam rollers with epoxy. I use 1/4" nap rollers cut in half so they are 4.5" long. and I usually tip it with a paint brush (disposable) or one of those plastic body filler spreaders.

I always use cheap plastic paint containers.. usually, after the epoxy is hardened, you can squeeze the container and the epoxy will pop off.

I use plastic paint trays for the same reason... and I put a home depot plastic bag around the roller so I can pull it off and toss it without getting my hands messy...

[asianflava]

If you are looking for rollers made specifically for epoxy, you can usually find them at a boat store like West Marine or Boater's World. In reality, most any roller will work. Like Arne, I use the plastic mixing buckets for the same reason. Epoxy isn't like solvent based paints, it doesn't "eat" thru things like plastics.

The thing to be careful of when working with epoxy is Thermal Runaway. If you mix up a lot in a plastic bucket it will get so hot (when it cures) that it will melt the bucket. Don't mix huge batches, try to work with small batches. If you must mix a lot of material, make sure it has a lot of surface area to relieve the heat that will build up from curing.

Oh and don't use epoxy and polyester resin interchangeably. Even though they are very similar, they are different.

[Muggnz]

The thing to be careful of when working with epoxy is Thermal Runaway. If you mix up a lot in a plastic bucket it will get so hot (when it cures) that it will melt the bucket. Don't mix huge batches, try to work with small batches. If you must mix a lot of material, make sure it has a lot of surface area to relieve the heat that will build up from curing.

And when it gets hot, it starts to give off smoke. Which at best will merely give you a headache.

And and if you've mixed it in a plastic container, the plastic might melt . . .

david

[Nosty]

Thank you all for your help. I haven't worked with epoxy before and I keep seeing this mushroom cloud eminating from my back yard and nothing but an old pair of sneakers where I once stood.

Well, off to the lumber yard.

Thanks again,
Brian

[starleen2]

One other thing about rollers for epoxy - use them one then they are useless after the epoxy gels on them. To save a few $$, I took a standard roller and cut it into three smaller rollers and tripled the use! Just be sure to defuzz the edges where you make the cut

[wannabefree]

For filler I used Famowood; the solvent based stuff. It hardens in minutes, you can usually get a good match, and if needed you can color it with Transtint dyes.

My mixing containers were paper salad bowls from the grocery store. They have the advantage of spreading out the mixed epoxy over a wider area than a cup, giving a few more minutes of pot life. Pot life in a paper cup was just too short for me because the epoxy heated up too fast.

[starleen2]

also you might want to consider some aluminum baking pans - the cheap thin disposable type. I bought a few to use with the rollers and they worked real well. When the resin cured, I just broke it out and reused the trays several times.. it also helps to dissipate the heat and gives a longer pot life, but mix small amounts so it won't "set off" in the pan

[Ageless]

If you live in warm climates; the ambient temps will hasten the cure of the resin. Store it in the fridge before using and the pot life will increase.

[angib]

The thing to be careful of when working with epoxy is Thermal Runaway.

All of the above is accurate but I do have to say that 'thermal runaway' is something that happens to men in white lab coats with bow ties. Guys with resin stains on their work denims have a 'hot mix'.

I've never seen epoxy get hot enough to smoke but that doesn't mean I haven't had it go off so fast that the brush I was using had to be pried off the workpiece it had stuck to.

Polyester resin, now that can get hot - not just smoke but full-blown flames aren't unknown.

Andrew

[Ageless]

All the years working with resins; we would at times need a 'hot mix' for a fast fix on a tool in production use. Normal ratio was 7% hardener but we would double it. The remains in the paper cup would get hot enough to steam but never set fire to the paper.

[Muggnz]

I've never seen epoxy get hot enough to smoke but that doesn't mean I haven't had it go off so fast that the brush I was using had to be pried off the workpiece it had stuck to.
Andrew

I'm sure I mixed it with the wrong quantities of each of the 2 parts. As that batch went "off" in under 10 minutes. And subsequent batches took longer. I suspect it takes longer with less of the hardener portion.

david

[Arne]

I cut my paint roller into 2 pieces on my radial arm saw. That leaves a square edge which leaves a line in paint. production ends are beveled. To get the same effect on the cut ends, I put the roller on the the paint handle and hold it at an angle on my grinding wheel.. If the roller is not clogged, it will spin and you wind up with a beveled edge....