[PSUBS-MAILIST] machining

[Sean T. Stevenson via Personal_Submersibles]

A full anneal with the part sufficiently supported to prevent any sag under its own weight. The part (steel alloy, I assume?) must be heated above its recrystallization temperature, held to soak through at that temperature, and then cooled very slowly. You can build a quick and dirty oven out of brick, using a gas burner? I do in situ heat treatments on large parts using electric heater consoles (resistive or induction), but these can be expensive to rent.

Your one end at a time trick might work. You just have to slow the cooling down even more by throttling the fuel or gradually moving the burner away over the course of hours - not minutes.

Sean

-------- Original Message --------
On Dec 24, 2017, 08:48, hank pronk via Personal_Submersibles wrote:

> Hi All,
> Looking for an old timer trick to soften a shaft without warping it.  I am on my second try and it is good but not perfect.  I had to soften the ends of a 20mm shaft so I could drill one end and make a keyway on the other end.  I heated the ends slowly until they just turned orange and let sit to cool.  I did one end at a time.
> Any tricks to this?
> Hank
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