The missing bit in my attempts to cast an aluminium dog’s head – melting aluminium.
Make a gas or charcoal powered furnace: youtube video by Grant Thompson which set this idea off.
The problem with gas and charcoal (+hairdryer) are they are noisy, seem a little hit-and-miss & inconvenient and are just too ‘fiery’ for me.
My design is based on the design by TAOW.
Aliexpress shopping list as follows
- Heating coil (NZ$3-4) 2200W so 10A at 220V. Says its FeCrAl (Kanthal), but who knows.
- Fire-retardant wire (NZ$ 7-8 for 5m….I needed < 1 m). I put a blowtorch to it and it is fire-retardant. I learn my lesson already on selecting wire gauge appropriate to your current.
- PID and Solid State Relay. (~ NZ$20). Also came with a K-thermocouple but…
- I got another thermocouple (~NZ$5) with a longer prober and higher temp range. Which I just noticed was from the “Relax Yourselves Store“
- I went to a demolition yard for the refractory bricks. Two-bucks-a-piece. They were salvaged from a *PROPER* foundry.
- A tub of refractory cement and a bag of silica sand (to bulk cement out a bit since it cost more than gold).
- Various scraps of steel for the frame.
- An old metal toolbox I picked up in a charity store to contain all the electronics.
- Some car engine enamel spray paint to tidy things up and hide my shitty welds
…to TAOW’s design:
- Ceramic shield. Sounds way more high-tech than it is. Sounds like something on the noise of the space shuttle – actually something built from bathroom tiles:
- Separates the electricity from the crucible and …..er… you. This seems to be a major design flaw to TAOW’s design…one that may well be his demise.
- Is a replaceable/ maintainable cassette design with the heating element arranged so the two terminals protrude vertically from the base.
- DIY Crucible and tongs (I got a MIG welder!). I have just gone with a thick-walled steel crucible made from salvaged steel tube.