Will Polyester Resin Stick to Wood?

[crokett]

I usually cast in Silmar 41 Polyester resin. I have a piece of pine that has a large bug tunnel along one side. The tunnel is partially exposed. I was going to try wrapping packing tape around the ends to seal them and fill the tunnel with casting resin. When the pen is turned, most of the wood sides of the tunnel will be turned away. Is it going to stick well enough on its own to the wood or should I use epoxy (the adhesive kind?). I could also drill some holes crosswize through the blank and let the resin fill those, although one side of the blank would then have dots on it. That might not be a bad thing though.

 

[jttheclockman]

Epoxy resins are your better choice.

 

[Kenny Durrant]

I think the PR will stick. The problem is that the resin shrinks as it cures and it might pull away. In my eyes that's not a sticking problem. Like JT suggested epoxy or a urethane resin would better for the job.

 

[JohnU]

As above, would recommend not using Silmar only because there are other resins better for the job. Personally I would use Alumilite Clear Urethane resin. If all you use is Silmar then be sure to warm the wood before casting to remove moisture or humidity from it. As said above, Silmar shrinks as it cures so it has a tendency to pull away from objects. As it shrinks, it pulls away from the outer edges of the cast along the mold. A way to help fight that is completely submerge your wood in the resin so there's no outer edge where resin meets wood, to pull away from. Good luck!

 

[crokett]

Thanks. I will look at some Epoxy resin for this one.