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+-- Thread: epoxy on poly? (/showthread.php?tid=7344946)
epoxy on poly? - mound - 12-10-2018
Does anybody know if West Systems epoxy will have trouble bonding to a surface that has polyurethane on it?
RE: epoxy on poly? - Willyou - 12-11-2018
I'm not sure what the answer is. I guess I have never tried it. If you don't get a good answer here, I suggest you do some experimenting. One thing to consider, however: If the epoxy does adhere to the poly, keep in mind that the joint will be no stronger than the epoxy/poly bond or the poly/wood bond. Not sure which will fail.
RE: epoxy on poly? - jklingel - 12-12-2018
I have a Varathaned table, and can chisel epoxy off quite easily.
RE: epoxy on poly? - anwalt - 12-13-2018
(12-10-2018, 01:48 PM)mound Wrote: Does anybody know if West Systems epoxy will have trouble bonding to a surface that has polyurethane on it?
From the chemistry, I expect that epoxy & polyurethane are compatible.
I recall a post some time ago that said that 'polyurethane' varnish is comprised of traditional varnish with polyurethane microspheres added for wear resistance. If that is correct, then the question is changed to 'is epoxy compatible with varnish'? I have no guess on that combination.
If your surface has been waxed, then the wax will need to be removed for any hope of adhesion.
Tom
RE: epoxy on poly? - AHill - 12-13-2018
It'll bond to the poly if you rough up the surface a bit with 320 or 400 grit sandpaper. That said, it's only going to bond to the poly and not the substrate. If you chip off the epoxy, it'll take the poly with it. Poly is just a surface finish.