Posted by Mark Farley on June 01, 2001 at 14:30:31:
In Reply to: Re: Bore Shrinkage After Heat Treat posted by Mel Eacker II on April 09, 2001 at 14:13:23:
When hardening the teeth to a pattern "A" type with induction, the bore should not move. Two things that may affect this are:
1. Is the material 4140 pre heat treated or annealed?
2. The second and more important is The 500 Bhn requirement would require a 600 deg F temper. The temper is probably causing the problem with the bore more than the Induction. Try raising the hardness requirement thus lowering the temper.