Here is a variation of the soldering iron. I temper my small pieces by heating a bar of steel on which the piece to be tempered is placed. This gives me a great deal of control because the steel heats more slowly than a small piece and the color is more discernable since it is not being held in a flame
I use a piece of bar stock steel, like the type you can pick up at any hardware store. I have several sizes, 1/8" X 1", 1/4" X 1", and up to 1/2" X 2"... all about a foot long. Be sure to clean all the bark off the bar stock.
I then choose the bar stock so it is wider than the part being tempered. I also choose the size of bar stock depending upon the control I need in tempering, thin heats more quickly than thick.
I hold the bar stock in a vice (flat side up, like a spatula, not a cake cutter) over my work bench. I then place the item to be tempered on the top near the end of the bar about 6 to 8 inches away from the vice.
The bar stock should be hanging over the bench, not over the floor. I then choose a medium to knock the part onto when the tempering is done. Could be a rag, can of water, or a tin sheet. It all depends if the tempering temp is critical. If you want to stop the tempering quickly, use water, if not, maybe just a tin can to catch it...
Anyway, back to the tempering, like I said, I use a piece of bar stock wider than the piece. This way no flame directly touches the piece and tempering is more consistent. The heat is applied to the bottom of the bar stock by a simple propane torch.
The steel bar provides all the heat, its very even and as we all know, small pieces of metal can go from being tempered to being annealed in just a few seconds
I hope this helps
Bruce
[This message has been edited by Bruce Jensky (edited 02-23-2000).]