can we use any 3d printed model as a cast pattern?
Here are the photos from the attempt mentioned above. again this isn't a how to, this was me and my brother thinking "we got a hot fire and a bunch of cans, why not try?" The first photo is the Part I designed to make just a surface cavity that we could fill just by pouring (4500). The second is the resulting ugly part (4501). The third photo is the puck I printed at the lowest fill and wall thickness I could and still get a flat top (4502), and the last photo is the resulting sprue that we filled and the resulting burn mark in the plastic (4503).
PLA works. Once you make your plaster mold, burn out the PLA, then cast in green sand. This will work for Al alloys and others just fine.