What's the max crucible size I can fit in a smelter made out of a used 30 lb propane tank ?

[rwm]

I used a castable refractory for my iron furnace. It showed very little wear after many firings. I built mine in a 15.5gal keg that had been decommissioned.

GsT

Do you remember the brand? I used Mizou on a furnace and that stuff is indestructible. Unfortunately it has high thermal mass.

 

[GeneT45]

Do you remember the brand? I used Mizou on a furnace and that stuff is indestructible. Unfortunately it has high thermal mass.

Off the top of my head, no. I'll do some searching. I chronicled my progress on another board (now defunct, but I have backups...), so I'll see if I can find it.

GsT

 

[kvt]

I have one made out of an old Propane bottle, Took out the valve, Blew air in it for a while, Then filled it with water before I started cutting it with air powered disk, It is small but works, Now I have a full size old heavy duty Keg that I want to make one out of. But for some reason have been having problems finding the refractory to use. Also thought of doing the wool stuff, then a layer of refractory.

And yes if you get hot metal on concrete it will explode from the moisture even if it is over 20 years old. Have seen it happen.
Good leather shoes and leggings are good, Ensure you do not have clothing that melts etc. Melted plastic type fabric hurts when it melts.

 

[durableoreo]

I'll echo the advice to start small and use the appropriate safety gear. Sorry to be such a square.

I never understood the obsession with using old propane tanks. They are the pallets of the blacksmith shop.

 

[GeneT45]

I never understood the obsession with using old propane tanks. They are the pallets of the blacksmith shop.

They're cheap and available - not much more to understand. My preference is to fill them with sand before cutting, etc.

GsT

 

[durableoreo]

This is barely relevant but melting cast iron made me think of this guy. He uses a silicon carbide heater inside a kaowool kiln, which is heated in a microwave oven. Home made crucible, too. It sounds like you have a much bigger project in mind but this is an interesting watch. Not a demonstration of safety equipment, though.

 

[rwm]

@maxime.levesque - Any update on your progress? Just curious.

 

[maxime.levesque]

I cut the propane tank 5" from the top (after first filling it completely with water, to avoid being in the news !), and now unfortunately the project is on pause, because I have no more "hobby time" for a aprox month or two.

When I get back to it, I will explore diesel burners, with air preheating.

@maxime.levesque - Any update on your progress? Just curious.