Troubleshooting one sided San Mai

[gables]

I started with a 1084 core of .125 and outer layers of .095 of 15n20. I get this pattern on one side after a quick sand and etch. The flip side reveals no pattern. This is at rough grind, pre HT with an edge of .125".

Did I forge more on one side perhaps?

[Lin Rhea]

Flip it up and look at the bottom of the ricasso. That should tell the story. It's either uneven forging or uneven grinding. You're in a game of thousandths and don't have the latitude to go far either direction. I see that you have ground the potential plunge up and out the top of the blade which cut down on your fudge room.

[gables]

Bingo. Thanks for the lesson Lin. Working on centering throughout is going to be great practice.

[rbcorbitt]

I like it, Gabe!!!!

[tomsm44]

Hate that happened.  Any chance you could grind the stock thinner to center everything up and then regrind the blade to a different shape/profile that's work with the size stock left?  May be able to make it into a smaller knife than planned.  Just a thought, but it may be more trouble than it's worth.  I'm sure it took a lot of time and work to get it this far.  It'd be a shame to have that work go to waste.  Please keep posting your progress with this knife or others like it.  I still haven't gotten to start forging yet, but hopefully soon.  I always liked the look and concept of san mai blades, so once I start getting comfortable with forging, that's something I'd like to try.

Matt Toms

[gables]

Thanks for the thoughts Matt. I have learned to stop on some blades sooner than I used to. With my hidden tang blades I am shooting for a high standard of journeyman smith quality. Although San Mai wouldn't make for a good JS test knife, the standards are still how I decide when to stop. I'm going to HT this first blade, convex, sharpen, test and bend to destruction.

I am working on my second billet now with this same thickness combination of steels. I think a better combination is going to be with my third test of a 5/32 core of 1095 and .060 outer layers of 15n20.

[tomsm44]

Sounds like a plan.  I am just a hobbyist and still a LONG way from JS level.  Since I don't sell any knives, all material cost for me is out of pocket, so I try to minimize waste.  I've considered doing some destructive testing with a couple knives that I made mistakes on, but haven't been able to bring myself to do it yet.  So far, I've been able to modify the design and remove the mistakes on most of them.  Post some pictures of the blade after or even during the tests you do on it.  I'd love to see what you find.

Matt