another slipjoint spring question

Joined
Dec 16, 2005
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114
hello everyone, I have a quick question/concern working on a knife tonight and I noticed that my spring is bowed from side to side, so I went back to the surface grinder and made sure everything was flat, take it off the surface grinder and noticed its still bowed, check the surface grinder and the magnetic chuck is drawing the bow out of the spring so its flat, any suggestion's? the spring thickness is .088 I hope this made sense has anyone ran into to this before?

thanks
 

SBuzek

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Dec 7, 2006
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Spring is warped, try to straighten by clamping to a flat bar and retemper.
Or make another spring.
 
Joined
Dec 16, 2005
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114
thanks SBuzek I re-heat treated and clamped in a vise during plate quench and it still looks warped, so your saying clamp it to flat bar while its tempering?
 

SBuzek

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Yes, clamp on one end, put a flat washer under the other end and clamp in the middle just passed straight.Temper again
 

SBuzek

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Several possibilities, what steel?
 

AVigil

Adam Vigil knifemaker working the grind
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Several possibilities, what steel?

I wonder if it is AEB-L
I have run into it many times, that is why I no longer use it for slippies
 
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Dec 16, 2005
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the steel is ATS 34, I have never noticed this before and I have made several out of this piece, but i have started paying more attention to detail.
 

Drew Riley

Riley Knife and Tool
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You generally can't grind a warp out on a surface grinder; at least not without shimming your piece first.

Set the spring on your chuck, warp side down, so that there's space in the middle. Figure out what that gap is, and put the equivalent shim stock under it. Make sure your piece is secure, and take light passes until you've covered the entire side of the spring.

At this point, you should be able to flip it over and grind back into parallel without shims. Make sure you're not overheating the spring while grinding too, as this can introduce warp as well.
 
Joined
Dec 16, 2005
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Thanks Drew, I will try that this evening, any thoughts on how this happens or preventive measures to keep it from happening in the future?
 
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