The Dreaded " PING"

JawJacker

JawJacker

Well-Known Member
Well, Not a complete waste of time, I did learn a few things.

1. Nicholson file 1/4 thick
2. Annealed
3. Shaped and beveled drilled 1/4 holes 2
4. Normalized it, one round of 1650 then air cooled
5. Heat treated with Evenheat 1450 no soak, brine quench
6. 1 hr 400 degrees X2 for temper
7. Noticed I had some warpage 1/16 off in the handle area
8. placed it in the vise applied very little pressure to straighten .....and
9. PING :what!:

Anywho, How does my grain look?? Im going to test the pieces in the vise Monday to see what happens.
 

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Forge gremlins strike again. I would have normalized X3. Maybe quench for about 6 seconds and then check for straightness and see if you have enough residual heat to allow you to straighten it. Taking the bends out is one of the most nerve racking things that you can do.

Oh, ya. The grain looks great.

Doug
 
Doug, I was thinking maybe I should have drilled the holes after the HT, Funny thing was I did 3 knives the same way and no problem and no normalizing at all. The only reason I normalized this one once was that I bent this 3 or 4 times while soft to straighten it, I figured I created some stress.
 
I always heat oil but never have heated the brine I just keep it luke warm and never had a problem. Thanks I will start normalizing 3X

Its funny I do all this when Michael Morris claims he takes a new file and just tempers it down enough to be worked and thats it, no HT. I may give this a go, if I can figure a good temper recipe.
 
I actually don't think that this has anything to do with the quenchant. If the hole generated the break it probably would have let go in the brine. We are dealing with a mystery metal here but I'll assume that it's something on the order of 1095 or a high carbon W2. With that assumption, I would raise the tempering temperature to 450° and extend the time to two hours keeping the two cycles.

If I find a warp in a knife after tempering what I like to do is to clamp it to a piece of angle iron with C clamps and shim the knife with something like a penny to counter bend the warp. I then repeat a tempering cycle. I use the angle iron because it's shape makes it more ridged. Just take it easy on cranking the C clamps down, you can always repeat the process again if it doesn't work the first time.

As you've seen in the answers some of us prefer to drill holes before hardening and some after. If you do it after you will need carbide bits and burs or you will need to draw back that hardness in the handle.

I don't know Mr Morris but drawing down the temper in a file and shaping it could work. It's not much different that some who deal with think blade stock preferring to harden the blank after profiling and then grinding in the bevels. They feel that this prevents warping better. The only thing about starting with a file is that you need to be sure that you are not starting with a case hardened one or you'll never make a suitable knife from it by any method.

Doug
 
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