Tuesday, December 30, 2008

Plastic Welder

I got a plastic stick welder for Christmas. Essentially it's a heat gun with a small tip and a knob on the base to control the temperature of the air. After messing about with the different tips and burning some paint off of a steel pipe, I remembered that some iron forges use a heater for the air before it goes to the blast furnace. So I took two tin cans, one large and one a bit smaller and poked a hole in the side of the big can, and found a short section of 3/8" iron pipe that the welder nozzle fit into. Two lumps of charcoal in the bottom and a few pop cans smashed into the small tin can, the fire lit itself from the welder heat, and quickly heated to cherry red and melted the aluminum into a few tablespoons of slag. Then it burnt a hole into the bottom can opposite the air inlet and jumped to white hot for about 10 seconds as the last of the charcoal vaporized. The tin from the bottom can had melted and stuck to the rocks underneath. This is much to small to be of real use, it's difficult to fit the scrap into such a small crucible.