Posts: 3,799
Threads: 184
Joined: Jun 2012
Location: Farmington Hills, Michigan
Nice job on the reamer Rick and a great write-up.
The way to prevent scale is to keep oxygen away from the part as it's heated. If you have a furnace, you can fashion an air tight box for the part or use a stainless steel envelope which you can purchase just for that purpose. Since you are using a torch, you might try putting the reamer in a pipe nipple with capped ends. An old timers way to consume any oxygen in the heating receptacle is to place a piece of paper in with the part. As the paper burns, it will consume any oxygen that is present and keep scale from building on the part.
Tom
Posts: 21
Threads: 0
Joined: Jul 2012
Location: Macon, Ga.
Thanks Tom. I seem to remember the paper in the crucible trick mentioned sometime long ago. I think I actually moved the torch too close to the reamer. A friend of mine swears by the "bean can" furnace for things like this. I may have to try that one next. He uses a Mapp torch and gets things plenty hot. No scale.
Ken, if I had some drop of suitable size, I would make another pair like these. I have a pair of jaws made from plain old aluminum angle that I use a lot too.
pamrick, proud to be a member of MetalworkingFun since Jul 2012.