Large Furnace
 Can't get enough of a good thing.
Small furnaces can melt small amounts of metal. Eventually I will want to melt MUCH metal, so I started on a larger furnace


The core of my new furnace, the top half of an old water heater and the frame from one of those old excersize trampolines.


I started by taking some old t-posts and welding them across the frame. These are the main supports.


Here is the water heater welded to the rails. I also welded some rebar supports, primarily to keep the body from wanting to rock at all and stress the points where it's welded to the rails.


This is the lid for the furnace, made from the top 4 inches or so that I cut off the body. The hardware that is welded inside is so that the cement has somthing to grab onto.


The body with the lid on and off. The handles are made from one of those cheezy 70's-ish shield wall decorations. My neighbor knows I do medieval re-creation and gave it to me.


Here's the lid with the cement in place. I poured a commercial castable refractory about an inch deep for a hot face, then when that was set I filled the rest with homemade.


Here's the first layer of cement in the bottom of the furnace. Again, this is the '2 Bucks' homemade formula. I'm using that where I think I can get away with it to help cut the cost.


Update 1-5-07




Here is the completed furnace, with the lid on. The lid weighs a good 35-40 lbs.


This is the body with the lid off. The empty spaces around the outside were formed with foamboard that was later burned out. At some point I am planning to fill these with perlite. If you look carefully, you can see a layer of whiter material lining the inner core of the chamber. This is a high-temp castable refractory cement. I rammed in a home-made mix with a larger chamber, then poured in the castable with a 9" core form in place. That gives me about 3/4" of the high-temp as a lining.