Yeah, I know... knife stuff.
Thought I'd post some details on the forge we built, because it was fun, simple, and works great!
Got the idea from Church & Son ( http://churchandson.wordpress.com/2011/05/01/lets-do-a-neo-tribal-forge/ ). We had an old crab cooking pot that rusted through, some 1 1/2" fence pipe, and a bag of sack-rete.
Punched a hole through the pot, fitted the pipe...
There is good, high-temp concrete available, but we had a bag of the plain, cheap stuff and wanted to see how it would do. We dished out the concrete to form a basin around the pipe, and covered the pipe with plastic.
For a bellows we tried a 5V fan on a reducer. Worked good, but not quite enough volume when the coal got hot. The fencing wire attachment was important for asthetics...
After the coal was hot and self-sustaining, the fan needed some help from the leaf-blower. Unfortunately, the leaf-blower was more than the little fan could take (we didn't remove it first) and after generating some power, it got too hot!
We bought some dryer ducting and will use it to route the blower-air into the pipe next time. Here is our basic setup. With a borrowed anvil, our total cost was ~$50. The tongs were $44 so only about $6 into the forge itself.
The test run went well. We got 2 65# sacks of coal, and used about 2 lbs of it this first run. Good and hot - and easily heated up some spikes for pounding. We also flattened some heavier nails quickly. Too quickly.
The forge worked great! Best of all, no evidence of the concrete cracking or any sign of damage. The one improvement we want is for our bellows. We are watching Goodwill for an electric blower, and the ducting will help keep the noise down and airflow up.
Best part of the project is our 15 year old son did most of the work. Pounding hot steel gets us tired quickly, and is a GREAT activity for teenage boys!
Now we need to find some useful projects to build BESIDES fat knives...