Does anyone have experience with epoxy finishes?

[badwhiskey]

I have a tabletop made from reclaimed chestnut and I'm considering an epoxy finish. Does anyone have any experience, tips, pitfalls or brand recommendations?

Thanks

[Herb G]

I'd use oil based poly or Alumilite instead.

[Wild Turkey]

What are you considering it for?  What are you wanting to gain from using epoxy?

I'd be afraid of it popping loose if there's any seasonal dimension changes.  I've seen urethane hold up quite well for many years of daily use and epoxy pop off concrete.

[badwhiskey]

The wood has many minor splits and deep grooves and flaws.  I will be filling the worst of them and the big knots with epoxy, so I wondered if I could use it for the whole thing.

[TomFromStLouis]

I would not try to fill the holes and layer on a finish in one step. I cannot tell if that is your goal but I think that could go wrong easily.

Maybe others do it regularly and with epoxy - dunno - but if they are two steps then there is no need to use epoxy for the finish.

[Bill Holt]

I have done it three times and most likely, never again.  At the time there were several guys on WoodNet who gave enough advice, I felt comfortable doing it.  System Three has everything you need, except the experience.  Over about a year I finished three mesquite slabs; the first two went okay.  System Three MirrorCoat cures to that "clear as water" look 99% of the time.  When it does not, I cannot express the amount of work required to fix the issues.

I could never recommend finishing with MirrorCoat even though it did ok 2 of the 3 times and hundreds, if not thousands, of customers have a good experience.  System Three has great customer service but they were unable to explain what happens in that 1% of the time.

I was told wood movement is not an issue when epoxy encapsulates the project.

There are a lot of great finishes on the market that do not have a steep learning curve; IMHO MirrorCoat is not one of them.

[Cooler]

We use epoxy powder coating in our commercial operations.  The choice are polyester powder or epoxy powder.

The polyester is UV resistant and flexible.

The epoxy is not UV resistant and will fade badly in the sun and break down.  It is much harder than polyester and it has a very high resistance to chemicals.

That is all I know on the subject.

[barryvabeach]

I had a piece with some splits and holes, and used epoxy and it came out great.  I used this brand, it was pretty attractively priced  https://www.amazon.com/gp/product/B01LYK...UTF8&psc=1   

I had a number of setbacks, but all due to operator error.

The instructions were a little confusing because they tell you how much time you should spend mixing the two parts, but that was based on fairly large quantities, and I didn't realize till the end that a shorter mix time, which will develop less bubbles, is better for smaller batches.


This was the piece in rough state    

[attachment=3408]
I did the first batch pretty small, and used a plumbers brush to basically get a thin coat on all the exposed wood where there were cracks and splits.
[attachment=3409]

I then made a big batch and filled most of the hole, though I misjudged it, and worked it after it had started to set, so i had to chisel some of it out after it dried.

I then did a final coat.  I think if I wanted a bar top finish it would have been fine, but I was making the desk for a very good friend, and another friend suggested that I put a quote on the table top for him.  To do that,  I used scrapers to get the epoxy fill level with the rest of the top, then applied a seal coat of shellac, stamped the top with the phrase, then made a very small batch and added some green tint to fill in the stamped letters.  That part went pretty poorly because you mix by volume, not by weight, and I had a great deal of trouble estimating volume, and ended up with a mixture that was sticky but never dried.   I eventually fixed it and it came out pretty well. In the photo it looks pretty dark, but in person, it looks like water, and in some places you can see the wood at the bottom, depending on the lighting.
[attachment=3410]

[badwhiskey]

Thanks for all of the replies, they were very helpful.   barryvabeach, that's almost exactly the situation I'm in so I'll look into that product.  Its very handy that is available on Amazon.  And good to know that West Systems is tricky, because that's the only name I know.

[barryvabeach]

The instructions that I got with the product were pretty clear that it had to be mixed correctly.  They even went so far as to say that you should not scrape out the contents of the mixing container when you pour - based on the assumption that anything stuck to the sides would not be very well mixed.  One of the biggest challenges for me was guessing how much to mix up for each pour.  If I were to do it again, I might try to do a trial pour with water a day or two in advance, to get some rough idea of volume.  Due to the sizing of the splits and cracks, i wasn't sure whether it would take a quart or a half gallon .  If you mix too much, you have to through away the unused portion, if you mix too little, you need another pour.  Making sure the proportions were exactly correct is also another challenge when making smaller batches - since you are trying to eyeball it.