Reprofile and still look pretty?

[Bob_G]

I guess it's about time for my first question after lurking for a month or so.

Back story - I bought my last knife 26 years ago (not counting kitchen knives, but that's still been 10 years or more.) A few months ago I found myself at the feline vet site and grabbed two SAKs. I was shocked at the price/performance ratio. So I thought I'd get something a little more expensive to see how that was (in other words, if you can get that good for 20 bucks, what would more get you?) Since I've always liked folders, I got a Ritter Mini-Grip.

I realized that I'd have to sharpen them, so got a Sharpmaker. It put such a nice (well, in my experience) edge on the SAKs that I then realized how bad the kitchen knives were, and that they'd have to be reprofiled, so got an Edge Pro Apex. I've been doing the kitchen knives for the last few weeks, and it's worked out okay. They all shave and once I get it started with a sort of angle approach, then all push through newsprint.

I'd been saving the Ritter until I had some experience, and it looks like maybe I should have waited longer On the kitchen knives I used a 15/18, and decided to go with 12/15 on the Ritter. Took 3 1/2 hours. Looks like crap. So sharp I'm scared of it. Really, the others "shave" but the Ritter shaves with no feeling of the hair being cut at all. It won't pop a targeted hair, but pulling it through my arm hair, a few fall out as it passes. But it looks like crap.

Two areas - the primary bevel as it goes "around the corner" toward the tip doesn't match the rest in reflecting light. It doesn't match in size either, but that's true for all of mine so far but the others don't look that different in surface texture as you near the tip. Worse, I managed to mar the flat surface in the same area from rocking the blade I assume, but not totally sure.

So, do I just need more experience, or is it almost but not quite impossible to reprofile something as hard as S30V to 12º and still have it look decent? Or should I care? Did I spend too much effort trying to raise a burr at the tip, which I never did manage to do? Should I have raised or lowered the angle at the tip? I'm thinking maybe I should have raised it.

Thanks for reading, and thanks for all the info I've gotten here.

 

[Cliff Stamp]

It is common for the edge towards the tip to be made more obtuse to keep it at the same width. reprofiling it to adjust the angle on the rest of the blade can take some time especially on a steel like S30V which is hard to grind. The longer it takes the more likely you are going to get a little sloppy as well and marr the finish so you might want to consider doing it in stages. Maybe just reset to 15/20 on the first pass for example.

-Cliff

 

[Nosmo]

I have experienced the same sort of thing when re profiling. I put it down to the fact that so many makers are leaving their blades too thick just behind the cutting edge. So your 12/15 has now left a very wide and ugly bevel.

Sadly with some knives, I think we have to forget appearance in exchange for performance.

 

[Bob_G]

Cliff,

I considered doing it in stages, but wanted to get the full effect of the S30V. I think a planned break might be a good idea though

Nosmo,

I don't mind the wide bevel - in lowish indirect light it looks kind of nice. It's under good light that the surface is so obviously uneven. I didn't do many passes with the finer stones on the primary, just enough to raise a burr, so maybe a little more polishing would help.

In looking around for stropping materials, I found some 45 micron water based diamond paste. Just to do something, I ordered some to try smushing on the 120 stone to help out. Never heard of anyone doing this, so maybe a dumb idea, but it seems like it might work - the 120 stone holds a lot of water so you don't have to rinse too often, and I shouldn't have to use it that much once things get established.

 

[thombrogan]

Email sent.

 

[Broos]

Hello Bob,
I wouldn't put oil based diamond paste on a water stone. Diamond paste comes as both oil or water based, so that would be something to check before trying this. Oil on a water stone should be avoided.
broos