A Few (Mostly H-1) Questions

[JNieporte]

I understand that it's too inefficient (from a cost point) for Spyderco to flat-grind their H-1 blades. If I have it sent to Tom Krein (obviously a professional) for such modification, would that void the warranty?

I've read about work-hardening and while I understand that, for example, a backhoe's teeth are work hardened, I'm still confused. The backhoe's teeth are rammed into concrete, producing heat and friction. This hardens them even further. Got it. But the heat and friction from running my knife blade on a ceramic sharpener is high enough to alter the heat treat?

Lastly, I have a warranty question. As an example, I'll use the FRN Dragonfly. Let's say I didn't like the blade shape so I threw it on a belt sander and now it's a tanto. I clearly voided the warranty by doing this. But let's say a warranty issue comes up that's not related to the blade modification; the permanently-mounted pocket clip broke off. Is the pocket clip covered under warranty because it had nothing to do with the tanto mod, or did I ruin the entire warranty with one dumb mod? (No, didn't happen, just asking.)

 

[softrockrenegade]

Yes it would void warranty and h1 steel has no heat treat , it's is hardened from grinding and sharpening and is harder at the very edge and tougher and softer at the spine similar to a differential temper .

 

[yablanowitz]

Work hardening is not entirely a function of heat. Abrasion - tearing away the surface of the metal using something harder - results in plastic deformation of the surface remaining, which translates to work hardening of the surface. If you bend a wire coathanger back and forth a few times, it hardens and becomes brittle, then breaks. If you do so quickly, it gets quite warm. If you do it slowly, it doesn't get warm, but it breaks anyway. The work hardening is independent of the heat generated.

As for the warranty question, the only way to be certain is to send it in and ask. I do recall reading a post by Sal where he said they could reshape the blade of a replacement knife to match a customer's modification, but I don't recall the exact circumstances involved. Ultimately, it is up to Spyderco W&R to decide . Personally, I feel that once I've modified the knife, I have assumed full responsibility for it from that point forth. Maybe I'm just old-fashioned.

 

[Joshua J.]

Work hardening is not entirely a function of heat. Abrasion - tearing away the surface of the metal using something harder - results in plastic deformation of the surface remaining, which translates to work hardening of the surface. If you bend a wire coathanger back and forth a few times, it hardens and becomes brittle, then breaks. If you do so quickly, it gets quite warm. If you do it slowly, it doesn't get warm, but it breaks anyway. The work hardening is independent of the heat generated.

+1:thumbup:

Work hardening is a result of messing up the preferred arrangement of the atoms in metal.

http://en.wikipedia.org/wiki/Work_hardening

Also. H-1 is cold rolled from a specific thickness to attain the final hardness for the blade. Grinding only gives a small booster afterward.
Flat grinding H-1 is not possible at a factory level because at the speed they grind the heat would warp the blade. Hollow grinds can be applied to both sides simultaneously, so the blade stays straight.

 

[The Deacon]

In the past Spyderco has, at least occasionally, honored the warranty on customized knives where the warranty issue was obviously unrelated to the customization. Whether that would be the case in any specific future case is impossible to say, since I'm sure a number of factors would come into play. For the Dragonfly you mentioned, best case scenario, you'd lose the custom work. More realistic scenario, the clip would not be considered a warranty issue and you'd be given the option to pay $20 to have a metal one grafted onto it.

Personally, if I modify a knife, or have it modified for me, I assume the warranty is void. That doesn't bother me because the only warranty issues I've ever had with a Spyderco were obvious the first time I handled the knife.

Paul

My Personal Website ---- Beginners Guide to Spyderco Collecting ---- Kiwimania ---- Spydiewiki
Dead horses beaten, sacred cows tipped, chimeras hunted when time permits.
WTC # 1458 - 1504 - 1508 - Never Forget, Never Forgive!
It's easy to grin when your ship comes in and good fortune and fame are your lot, but the man worthwhile is the man who can smile with his shorts twisted up in a knot. - Morey Amsterdam

 

[Splat]

Personally, I feel that once I've modified the knife, I have assumed full responsibility for it from that point forth. Maybe I'm just old-fashioned.

:thumbup: Yep. Same here.