Lost Foam Copper Pour: Did It Work?

I attempt lost foam casting for the first time, pouring over 13 pounds of molten copper into my sacrificial pattern. I began by cutting multiple strips of one inch polystyrene foam board and gluing them together to get a large enough piece to make my form from. I used various woodworking tools to shape and finish my pattern, before coating it several times in drywall mud. After drying in the sun for a few days and getting knocked down by the wind ( I'm pretty sure this is what caused the cracking) I buried it in a bucket of sand and poured a full crucible of molten copper into my pattern. After spewing noxious smoke and flames for a couple minutes it was done. I gave it ample time to solidify after my last casting mistake, before pulling it from the sand. I found the gypsum had done a good job holding the surface, but many veins of copper had flown out and it required some extra finishing work. I suspect had the pattern not been blown down and cracked the shell it might have given a near perfect surface finish... But we make lemonade out of lemons and moved forward, finishing it up on the belt sander and gave it a nice hammered finish for a bit of extra grip. The finished billet came out at 13.5 pounds, and Tim was thrilled to add it to his tool kit to work the next boulder of obsidian he digs up. You can check out the full Knapp-in experience on this video https://youtu.be/G0tMgTKRtco Patreon page. https://www.patreon.com/c/MacGarvins As an Amazon affiliate I earn from qualifying purchases, links below help support the channel at no extra cost to you! Products used in this video Vevor 12kg furnace https://amzn.to/4fByzIF Rigidizer for ceramic wool https://amzn.to/4wlkoys Satanite refractory coating https://amzn.to/4hznIRY Ingot molds https://amzn.to/4gUS1Ta Aluminized gloves https://amzn.to/4wf0jtG #backyardmetalcasting #foundry #diy #flintknapping #coppercasting #lostfoam #toolmaker