Welcome to the forum!
I'm over the hill, and picking up speed.
I started out on a small scale. This is a small freon tank, I think it's 9" diameter. It has a fireclay/foam mix for insulation and commercial hotface. I've melted cast in it using a graphite crucible and up to about 6# Aluminum in a clay crucible. I've built a larger furnace but haven't needed to pour anything that large yet.
A 55 gal drum is pretty big to start out. Most use a 20# propane tank or similar to start. Remove the valve and fill with water before you cut it, to be safe.
