That's a wonderful project and I like your crib/sled idea. Don't be shy! please post progress pictures.
Dovetail's generous offer is interesting, too. It would be nice to be able to identify the wood.
Finally, where do you get your walnut shell medium?
'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton
Please edit your profile with a name and location so we can better assist you and make for a friendlier forum.