Epoxy Finish

[Luckbox72]

I am work on a set of corn hole boards and the Die-Cut decal was very fine and had a minor issue in the transfer. A few pieces did not stick and I have a couple of raised areas when it is not sticking. I did a very thin coat of polycrylic to get everything to stay in place. I was thinking of just doing a thin seal coat of epoxy resin and then finishing with a couple of coats of polycrylic to keep a satin finish rather than the high gloss or the epoxy. The instructions for the epoxy say I need to keep the temp above 70 for 72 hour for proper cure. Since I am not doing a flood coat is this as important. I can try to setup a tarp and drape over them and use a small portable electric heater to keep it in the temp, or should I just stick with the polycrylic until it builds so that the boards are smooth.

 

[AllanD]

I suspect it will cure just fine if moderately cooler, just take longer. Not sure which epoxy you are using but the ones I have used have options of fast, medium, or slow hardener. I have used MAS epoxy for instance with the slow hardener and it cured overnight in an unheated garage.
You are correct to top coat it since UV light eventually degrades the epoxy.

 

[TENdriver]

I’m not an expert on this, but I think you may want a topcoat that incorporates some UV blockers.

I bet the boat builders know the best answer.

 

[Jeff]

A few comments and questions.
1. Are your boards made from plywood and regular construction lumber like most of them?
2. They'll only be outdoors once in awhile in the rain or sun when they're being used. Is that correct?
3. They don't need to be coated with epoxy, but if you've already done it then carry on.
4. Polycrylic is fine for a coating.
5. Why didn't you just finish them with latex paint instead of fancy woodworking type finishes and then apply the Die Cut stencils?

 

[Gofor]

The epoxy will finish curing at lower temps but does take longer. A rule of thumb we used for 2 part epoxy coating cure was: Double the curing time (i,e tack free; time between coats, etc) for every 10 degrees below 70, (70 degrees down to 50) and cut it in half for 10 degrees above. (70 to 90). These were sprayed coatings thinned to get the correct viscosity, so not sure it would work for a thicker brush-applied coat. Best to put some on a scrap piece (coupon) so you can gauge the hardness without messing up the work piece.

Polyurethane has better uv resistance than epoxy.