I'm happy to report we're now starting to get work done on the interior, which is the last phase of this thing. Started the day, though, by finishing up some of the wood stained trim on the foredeck.
18th and 19th Century goods and technologies. Check them out.
At any rate, our reduced version of the hearth begins like this: We created a platform for the fire surface out of two layers of 1/2" duroc (this is a concrete board used under tile, very solid, very flameproof, and very easy to work with).