My first knife and what she taught me

[Dan Zawacki]

Well, for those who are impatient, I'll get the pics out of the way first:

1084. Stabelized buckeye handle with a buffalo horn guard. Moasaic pins, and a high gloss, but just shy of actual mirror polish. 3-5 micron compound.

Hardened by watching the shadow line move across the blade as I heated as slowly and evenly as I could in my forge. Once the whole thing was above critical, I plunged and agitated in preheated (about 140 ish) parks #50.

First time, I interrupted at a 5 count (I may count a bit too quickly) but the smoke that billowed off was very volouminous and fast, an indicator that I interrupted too soon. Back into the heat it went, re-austenized, and quenched for a 9 count. This seemed to do better, as the smoke was wispy and slower.

Then I allowed the knife to cool until it was roughly the temperature of hot water from my tap (uncomfortable, but not likely dangerous), and then I submerged it in hot running water, which I cooled in increments, slowly, until the blade was cold to the touch. I did this to help be sure the martensite transformation was as complete as I was going to get it. I then double tempered, ending at 375.

I learned some very valuable lessons here.

1: even the last buffing pass is a time to be careful. Blades break when you get too smug that "it's all done now"

The broken tip happened when the buffing wheel grabbed the point on the last pass. Had I been paying a bit more attention, I would have flipped the drill over and buffed AWAY from the point. DOH!

2: 375 degrees (F) may be a bit on the low side for tempering 1084

After hardening, I tempered for 2 hours at 350, then cooled back to room temperature, then tempered for another hour at 375. I figured if I mussed up the hardening, the double temper may help convert any retained austenite, and the newly formed martensite would need a tempering. 400 would probably have been better.

3: even a complete amature can turn out a hard blade with a fine even grain.

The blade hardened quite satisfyingly, but a bit farther down the tang than I had wanted.

See that pig ugly hole in the guard? That's where another pin was supposed to go. I had no problem drilling the other two, but the bit walked when it tried to cut the hardened steel, and opened this hole up to malformed proportions.

Having broken the knife, I figured I should use this oppertunity to learn all that I could, so I looked at the grain in the broken ends. To my, admittadly inexperienced eye, it looked small and VERY even. This may have been due to the normalizing I did before hand grinding. It may have had something to do with the accidental double quench, but I'm not betting much on that.

Which brings me to lesson 4: Drill THEN harden!

and finally 5:

Being the maker, I have the wqonderful flexibility of changing the design a little, and ending up with a perfectly acceptable finished product.

I'm going to be grinding the spine down to form either a clip point or a drop point. Not entirely sure yet which. I figure I'll trace it out on paper and play with the drawing a while and see what strikes me as attractive.



Comments?

 

[jmar595]

That is a very nice first knife. I think you learned a few things beforehand also. I think a drop point would look good on that knife.

 

[Stacy E. Apelt - Bladesmith]

Good first job.
You learned to do all your planning first - like drilling holes.
Temper at 375-400 .
I love buckeye burl. It is my favorite wood. It goes well with ebony (and buffalo).

Some comments:
If you messed up the hardening, you can't fix it in the temper.

You can cut short pieces of rivet material and epoxy them in the bolster holes from both sides. This is called a pseudo-rivet.

The handle looks a bit thin, especially at the bolster area. It may fail there if any side pressure is exerted during use.

Fill out your profile, so we know a bit about you and where you are.

Stacy

 

[Dan Zawacki]

Thank you. Excellent advice! Especially on the rivets. That should help clean up the biggest cosmetic ouch I seem to have left.

Yeah, the handle is a bit on the thin side, but I never pictured this knife doing any sort of heavy work that would challenge that area. Mostly, it's a delicate slicer, and the heaviest work I would see it doing would be pinch hitting for a fillet knife.

I wasn't so much as trying to make up for a messed up hardening, but rather trying to be sure I didn;t have a problem with retained austenite.

Not that 1084 is particularly prone to that in general, but not having any more precise tools available than my home made gas forge, my beginners eye for temperature, and the electric convection oven in my kitchen, I am just trying to make the most of what I've got.

The way I see it, there is very little point whatsoever in spending the kind of money required to get ahold of real professional knifemaking tools if I can't make the most of the tools I already have access to.