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Carter wrote: ↑Wed Jul 18, 2018 10:17 pm This is a western handled 180mm funayuki in 52100 carbon steel. The handle is Oregon maple that has been dyed and stabilized, the bolster and pins are nickel-silver. The saya is Indian ebony with a knurled nickel-silver pin.

I totally dig it, nice work!

The knife gods often demand a blood sacrifice. I always wear eye protection, almost always a respirator, but never gloves. Not interested in having anything pulled into equipment and having my hand mangled...

Know where your coming from Carter. I work in maintenance and have more than my share of cuts and scrapes on my hands and knuckles. I don't like wearing gloves most of the time because of muted feel but try to when I can.

I make regular sacrifices to the knife gods...although less and less. I took about a 20yr break from woodworking and getting into the custom knife handles 6+ years ago reinvigorated my desire to build up a new workshop. Being older and having more $$, I decided to make safety a primary concern, whether with safety gear or the type of tools. The second and third priorities were more accurate higher quality tools and shop cleanliness. I am pretty good on the safety front, but admit I should wear the respirator a little more. I am not a glove guy except for my heat resistant gloves when pulling blades out of the HT oven. I do get tons of little cuts and abrasions, but I've been lucky not to have had a bad accident...stitches once, but still I was lucky with that one.

This is a 150mm petty I am working on in W2. It has been differentially hardened to 64-65HRC. At this point, it is about 90% done, it still needs some polishing and final sharpening.

Thought I would show the first blade made of W2 that I heat treated. I put clay on it for differential hardening and then heated it to 1460F before quenching in water. I knew the water quench was risky, but decided to give it a go. All seemed good, but shortly after pulling it out of the water, I heard the dreaded ping...a large crack developed at the choil area. I then noticed a second crack closer to the tip....I dropped the knife to the ground to see what would happen and the whole tip came off. Straight out of the oven and water quenched, the blade should be around 67HRC and very brittle. I wasn't happy with the result, but it kept me from having to purposely break a blade to view the grain structure. I was pleased with the grain in this blade....it is very fine. I never tempered this blade, so it is still very hard. I cut a 10 penny nail with it and there was absolutely no chipping or rolling of the edge....I thought it would chip due to the high hardness.

The second W2 petty I made, the one in the post above, was quenched in heated canola oil (same as I use for 52100) and it came out like a champ. I also made 2 other W2 blades and did an interrupted quench of oil then water....all seems good with them. I am getting a bench top Rockwell hardness tester next week, so I will be able to accurately measure the hardness of my blades. These W2 blades should be a little harder than my 52100 blades.

Ah well the joys of learning. Betcha the rest will be AWESOME!

Seeing first hand why Honyaki blades are so expensive....

Man that hurts. Looks like a great blade shape too.
Curious, does it bend at all, or just clean snap?

There is definitely a learning curve...fortunately, this steel is similar to 52100, so the heat recipe is similar...just some different temps for each of the 7 stages.

Yes, especially with the water quenched blades....I think I will try again with heated water and see what happens. Where the choil crack developed, the choil had a little bump or rough area, that could have been the fracture point and cause. I made sure the following blades with more smoothed out there. Water is supposed to yield a more visible hamon, after that, I am not clear on the benefit of water vs oil quench. A sword maker from Atlanta uses an interrupted quench of water then oil....that is what I did on the last 2 blades...they just finished tempering.

I have not done any destructive testing on the other blades....the 150mm petty in the post above is close to being finished, not going to mess with it. One of the knives tempered yesterday is a 200mm line knife...I may put it in the vise and pull on it. My 52100 blades will bend 90 degrees as I shown in an earlier post, I would think this will be similar. Will report back.

EDIT: I did test the bending of the 200mm line knife. I took it to about 45 degrees with no issues. Confirming my suspect, the differentially hardened blade will retain some of the bend, similar to a san-mai or clad knife. My 52100 blades that are not differentially hardened will retain almost no bend, even after a 90 degree deflection. Also, cutting a nail did not chip or roll this blade. Can't wait to get my hardness tester and verify HRC.

Wondering how many blades could take a 45% bend an not break. Betting not many. As always your knives rock.

Ut_ron wrote: ↑Sat Jul 28, 2018 9:23 pm Wondering how many blades could take a 45% bend an not break. Betting not many. As always your knives rock.

This 52100 blade has been tested to 90 degrees in both directions more than a dozen times...never even close to any issues.



The 200mm line knife that I tested earlier today has been finished ground on the grinder, sanded and etched up to 1200 grit. It was then sharpened to 6000 grit + strop, it has a very nice hamon...I invited her to dinner prep tonight and she surpassed my expectations with diced potatoes, peppers, raw bacon, and slicing cooked steak.

Awesome but my wondering was on other makers. Would not dare think of doing this on any of my blades.

Color me impressed with the durability of your knives.

Ut_ron wrote: ↑Sun Jul 29, 2018 3:31 pm Awesome but my wondering was on other makers. Would not dare think of doing this on any of my blades.

Color me impressed with the durability of your knives.

I wouldn't do it on any of the knives that I have purchased, but I feel it is incumbent on the knife maker to do some destructive testing, to study the grain structure, and be able to verify hardness.

Love Carter's stuff. Keep posting.

Carter wrote: ↑Sun Jul 29, 2018 6:00 pm

Ut_ron wrote: ↑Sun Jul 29, 2018 3:31 pm Awesome but my wondering was on other makers. Would not dare think of doing this on any of my blades.

Color me impressed with the durability of your knives.

I wouldn't do it on any of the knives that I have purchased, but I feel it is incumbent on the knife maker to do some destructive testing, to study the grain structure, and be able to verify hardness.

+1

nevrknow wrote: ↑Sun Jul 29, 2018 6:38 pm Love Carter's stuff. Keep posting.

Thanks, I appreciate it.

I used to do a lot of quail hunting in Aiken....great times.

It seem to be the consensus to go with the interrupted quench doing w2 for sure, most of the people I have talked to will only bother doing white#1 with water.

Carter wrote: ↑Fri Jul 27, 2018 1:36 pm Thought I would show the first blade made of W2 that I heat treated. I put clay on it for differential hardening and then heated it to 1460F before quenching in water. I knew the water quench was risky, but decided to give it a go. All seemed good, but shortly after pulling it out of the water, I heard the dreaded ping...a large crack developed at the choil area. I then noticed a second crack closer to the tip....I dropped the knife to the ground to see what would happen and the whole tip came off. Straight out of the oven and water quenched, the blade should be around 67HRC and very brittle. I wasn't happy with the result, but it kept me from having to purposely break a blade to view the grain structure. I was pleased with the grain in this blade....it is very fine. I never tempered this blade, so it is still very hard. I cut a 10 penny nail with it and there was absolutely no chipping or rolling of the edge....I thought it would chip due to the high hardness.

The second W2 petty I made, the one in the post above, was quenched in heated canola oil (same as I use for 52100) and it came out like a champ. I also made 2 other W2 blades and did an interrupted quench of oil then water....all seems good with them. I am getting a bench top Rockwell hardness tester next week, so I will be able to accurately measure the hardness of my blades. These W2 blades should be a little harder than my 52100 blades.

Carter, what is the advantage/disadvantage of doing water v. Oil?

Kalaeb wrote: ↑Tue Jul 31, 2018 2:12 pm Carter, what is the advantage/disadvantage of doing water v. Oil?

Water - higher potential harndess and a more delineated hamon, but risky for cracking

Oil - more forgiving, but lower post quench hardness, but shouldn't be a factor as blades will be tempered to a lower hardness than the quench hardness. I am using heated canola oil, same as for 52100, it is an ok quenchant...the preferred oil is Parks 50 (or equivalent)....it will cool the blade quicker than canola, but it is $$$ and is harder to get. I am getting my hardness tester tomorrow, so I will be able to verify my results....hoping I am happy with a straight or interrupted canola then water quench.

More W2 blades ready for handles....top is 200mm line knife and bottom is 150mm honesuki. Hamons are much more visible in person. Both of these have been used in my kitchen with good results, I'm happy with W2 so far and it is less reactive than 52100.