Question about sealing before molding

[Spockr]

I've made a part that is comprised of wood, metal and aves apoxy sculpt. I plan to make a mold of it with either Amazing Mold Putty or Smooth-on Mold-Star-15. I've sanded the wood part smooth but am concerned that the grain will imprint into the mold. This would be bad since the part is supposed to represent a smooth metallic surface. To prevent the wood grain from showing it seems like I'll need to apply something to seal the part and keep it smooth.

What material should I use to seal this part? Primer? Gesso? Other suggestions?

Also, how long should I let the sealed part cure before making the mold?

Thanks,
Matt

 

[ScaleModelMadman]

Primer, paint etc. should work just fine. A friend of mine who casts resin often primes the master depending on what it is for just this very reason.

HTH

 

[MrNatural]

to be extra sure you could cover the wood parts with bondo and sand them smooth then primer. I've seen people do this with balsa wood and their molds came out perfect.

 

[Grendels]

I just used MrNatural's advice on a cardboard tube with good results.

 

[Dusky]

You could use sanding sealer such as Miniwax's.