Balsa Foam

You must say "Richard" Blick to get around the nanny-bot on this site.  Likewise, the famous comic strip detective must be referred to as "Richard" Tracy!

Sorry I have no answer to your question, but I think the nanny-bot situation is hilarious!

Are you referring to what is known as patternmaker's foam?  Like Rennshape and other brands?

That is great stuff and I love it.  However, the only sources I know of want to sell it only in four foot by eight foot sheets and it costs a fortune!  If someone would sell it in smaller quantities, say 1 square foot sheets of the one inch and two inch sheets, I'd sure buy some.  It is even easier to carve than balsa or basswood, and fills as easily for painting.

I use it a lot in my day job. It's expensive, although I agree Blick is a good source and has discounts

Putting a hard smooth finish on it is a mystery to me. The best I've been able to come up with is thick acrylic polyurethane house paint.

It's extruded phenolic foam and the dust is not good for you.

The stuff I used filled up well with about three or four coats of Krylon primer.  That primer is very full-bodied with a lot of solids in it.

One more question on the balsafoam: I'm going to attach a styrene deck to the balsafoam hull...what adhesive will work best to keep the styrene permanently attached to the foam?

Epoxy will work.