|Project: Lucifers Kettle - A furnace for Aluminium|
Amx109 Rol: Werkt aan: Geen projecten :(
|Kennisgebied(en)||angle grinding (fugu'ing), welding, cement mixing, not being on fire|
|Projectoverzicht – Project toevoegen|
A furnace for melting aluminium
We built a 'bucket furnace' derivative so that we can melt aluminium for our various needs; mostly casting into other objects for CNC milling or just casting 3d prints a la the 'lost wax' method.
We were donated a rolled steel wood burner. The modifications were as follows:
- Remove chimney
- Remove top of chassis
- Weld one door closed
We made a refractory mix using sand/portland cement mix, sand, and fire rated cement. Most of the mixture was guessed. It was equal parts sand/portland cement mix and sand, with an added measure of the fire cement and water.
The base was lined with cement and made level, with a hole for any spillages.
Once that was dried the walls were made by using cardboard and mate bottles to reinforce our temporary cardboard walls. This was then finished with a layer of cement.
Forced air was needed to keep the temperature's high enough, for this we added some tubing:
- Added a ring of central heating tube to allow forced air injection
- Added a tube from the outside, connected to the inner ring with a pressure hose adapted for the forced air hose.
We used a 10cm stainless steel pipe that we cut to length. From the top of that tube we cut out two sides to allow us to lower the crucible into the furnace while still keeping a bit of metal above the top of the furnace on which we welded 2 sets of rods. The lowest two are there to keep the crucible from falling into the furnace, and highest two are there to lift the crucible from the furnace.
Finally we added a notch near the bottom of the crucible that allows us to pivot the whole thing and poor the molten metals onto the mould. To aid in pouring we created a small "v" on one end of the crucible.
We then created a pair of scissors allowing us to lift the crucible out of the furnace. On the end of these we added two small pipes which we can put around the stubs on the crucible, allowing it to tilt without any danger of falling or slipping from the scissors.
The first cast was made with a piece of wood that obviously immediately caught fire during the poor. The results however where pretty good, the metal was of a pretty good consistency and not much metal stuck to the crucible. We can clearly see the various ridges in the wood on which we poured.