Hi guys, Im getting set up to make a pair of 1/4" hollow/rounds. I needed to make a scratch stock to help shape the soles. (Suggested in two of the books Im using.) I tried to anneal a Garlick scraper so I could shape a scratch stock blade from it - failed miserably and still cant cut it after 2 attempts. Next I tried an old sawzall blade. After 2 attempts I got it softened enough to cut with a bimetal hacksaw blade and filed to shape. She works pretty well. But I cant figured out why I had a hard time with this.
I used a map gas torch. I let the blade get bright red (to my eyes, it never got orange, but maybe Im wrong). I put it in a can full of lime (insulator) and let it cool. After one pass through this, it couldnt be cut with a hacksaw or filed - both just skated across it the steel. After the second try the sawzall blade was better, but that scraper was still uncuttable.
Can anyone see what Im doing wrong here? For example, could I be getting it too hot?
Another odd sign - the stuff Im reading says that when its hot enough the blade will no longer be magnetic. I tried that magnet multiple times during the process - this steel was ALWAYS magnetic.
Clearly, Im missing something. Can you please give me a hand?
Many thanks,
Fred