I've used a stainless steel tube (motorcycle muffler) to melt aluminum (using charcoal) and I'm wondering why I couldn't just put a SS tube, inside a bigger SS tube, and fill the space in between with sand? Or clay?
The SS muffler casing, actually works fairly decent with NO insulation......
I've since made up another using a propane tank, with refractory cement/perlite mix. I haven't tried it yet, and would like to have a backup plan if it doesn't hold up. (which I'm afraid, is likely)
So please,let me know if I'm wasting time even thinking about it?