HELP! Heat treating a sword

[Hagar]

I finished the sword. Its a katana, 1/4" thick 3ft overall, 440c. (its a wall hanger so the customer wanted the 440).
Got it back from heat treating and it warped bad. Going to anneal it and straighten, but there is no guarantee it wont warp again when heat treated.
I have had this guy do swords before with no problem. He cant get it out of his furnace while it is still hot to straighten the blade. any suggestions? other heat treaters etc. all comments welcomed. THANKS
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There is no such thing as "good enough", either your work is good or it is not. How is your work?

 

[Larry Chew]

A few questions:

Is this being done in a vacuum or atmosphere furnace?
How is it being fixtured?
Which way did it warp?

If you do a true full anneal you should be able to get it straight. When you get it hardened again have the heat treater pay careful attention to fixturing, ramp rate, temp/soak time. Have it drawn back to mid 50's Rc. The lower hardness will be more forgiving if you need to do any minor post heat treat straightening.

Next time request a stress relief cycle before heat treat. It is easy to impart stress on a blade of this size while working it.

You might also consider only roughing in the blade before heat treat, then finishing it hard.

Larry