Jerry, I know this may be very subjective. But, could you give me the low-down on what your edge thickness is prior to sharpening? I realize this may all depend on the size and usage of the knife, and that's what I'm looking to hear. Has your thinking on this changed over the years given the new steels available?

Many thanks,
Chris

I am all over the map on this one. It depends on all the things you've mentioned. The most extreme example is a machete, which I've made 0.110" thick and will just sharpen it from there, running a wide convex edge as much as 3/8" up the blade. At the other end of the spectrum, a small utility knife in 3V or S30V, I'd probably thin it to about 0.010-0.015" before sharpening. Most tacticals, on which I want a strong edge, I keep them about 0.040" and use fairly slack belt to produce a convex edge. For hunters, which I think are more subject to abuse than most people think, I use about 0.025". As I read this I realize it's probably more confusing than helpful, but ask please questions if I can elaborate on anything.

No Jerry, that is exactly what I was asking about. I guess my only other question is whether you keep anything (like the tip) slightly thicker because you know it will see more abuse, or is everything ground evenly.

Chris

I keep the point heavier on stabbing blades only, not on utilities or hunters where you sometimes need a fine point.

Jerry,

I use the same exact measurements on my stuff. Great minds must think alike;)

Must be so, Chris. It just took me a LOT longer to get there than it did you... :)

Hello to all makers,

Aside from keeping the tip a little thick, what about other methods. I have tried 2 different ways - either shaping the blade so that there is plenty of blade behind the edge (the tip always has around a 90-degree angled shape to it) and secondly, while tempering and drawing down the spine, I give the tip a very, very quick blast with the torch, just enough for the tip to turn blue while the rest of the blade stays straw. I had no tip breakages since I started doing that on fine-pointed knives.

Have you done anything like this and if so, has it worked for you ? I know its a little different from the original question of edge thickness.

Thanks heaps.

Jason,

I dont want to turn this thread around, But this is a question I have been toying with. If I grind a thin point I also let the tip go blue. If a thick point is ground I will leave the tip alone. I have tried to break the tip and it has a spring to it and can sharpened.
I believe this is a form of differential heat treat.

Dan
www.theknifemaker.com

Have any of you guys used the two compressed paper wheels for putting the first edge on a new knife?

I just completed my first knife (in 61 years), and big California Bowie, and I'm ready to sharpen it.

If you know anything about those paper wheels, I'd love to hear from you.

Thank you!

Gene

Gene, I use my belt grinder with a 220 grit (that is used) and after I draw the wire edge, I use the cardboard wheel with polishing rouge. This polishes the wire edge off for a good edge. The abrasive wheel puts on a different egde than I use, so I dont use it a lot. Somebody else out there may know more details on how to use it. Good luck.

Jason and Dan,
That is an interesting concept. I never thought of doing that however a light bulb just came on. I am going to have to play with this.

Craig

I also use a slack belt, starting at 120 or 220 depending on blade size, to lay in the initial bevels and proceed out through the finest grit belts I can get (Norton Norax #5 which is about 2000 grit). Then I touch it lightly to a loose buff with white compound to flick off that last little bit of wire.

I think the cardboard wheels are for sharpening an already shaped edge and would be tough to use for laying in the primary bevel. I've not used them though and could be very wrong about that. If you don't have a grinder available, I'd probably use a series of wet and dry papers on a hard backing like a small flat board, starting at maybe 80 grit to lay in the bevel and running out in finer grits as far as needed. After that, the cardboard wheels might work OK.

Hi Jerry -

Thank you very much for your kind reply!

Lemme explain here for a second: I made this knife by stock reduction, and when I made the blade I didn't have a "real" belt grinder. All I had was a Mickey Mouse little Sears Chinese belt sander. But since this was flat gound, that was sufficient.

And, objectively (I think) it really turned out beautifully.

But then, after it was heat treated, I bought a new Grizzly 2 x 72 grinder for the other knives I'm making, which are hollow ground.

But I'm new and dumb, and earlier on, when I saw these paper wheels for sale, and after reading somewhere that guys use them, I bought a set (they're very cheap). But, when I got right down to sharpening, I put up these posts, trying to learn whether there were any special tricks to using these wheels. THEN, FOR THE FIRST TIME, I learned that not everybody is crazy about the wheels, and most of the makers do their sharpening like you do.

But I had an old Bowie blade which was ruined in heat treating, so I tried it on the wheels, and they REALLY produced a fine 20 - 25 degree extremely sharp and uniform edge. I was really happy with it!

So - what the heck - I just went ahead and ground in and buffed an edge on my new Bowie with the paper wheels, and I am extremely happy with the result.

Of course it does not have the "apple seed" edge most of you guys seem to prefer. The wheels produce strictly a flat edge, rather than a convex edge like yours. But for this particular knife, for my son, that's what I wanted anyway. It will never be used for hacking or heavy bone cutting. In fact, the knife will probably never be "used" at all; it'll only be "shown".

The wheels produced exactly the edge I wanted, and I am delighted with them. I realize a lot of edges will shave newspaper print, but this edge will do that also, yet it's not a "straight razor" edge, it's a good strong cutting edge.

But on my next knife, the big Persian Fighter, I'll use your technique.

Thank you very much!

Have a Happy Thanksgiving!

Gene

Gene, I know a knifemaker I respect very much who uses those wheels, and also uses them to sharpen industrial cutter blades. He swears by them. I didn't think they would cut well enough to profile an edge. If it works, it works and that's all that matters. No need to be apologetic. The people who do best in this business are those who try things and are not afraid to mess something up in the effort. I'll bet the best knifemakers have thrown away the most steel. :)

Thanks for the note, Jerry, you've very kind.

There is one little matter I forgot to mention, however, which has a bearing on the overall merits of the RAZOR EDGE KNIFE COMPANY paper wheel system.

As I mentioned, I tried the gritted wheel on the throw-away Bowie blade. But the blade was fairly sharp before it was heat treated; possibly a 64th or less. And I only made about, I don't recall exactly, perhaps three passes on each side, and it would shave, with only a burr up near the point. So I did not use the buffing wheel on that junk Bowie blade, because I was not interested in making it a flawless edge.

So then I did my new Bowie blade, as I mentioned, plus I also did use the white compound wheel for this blade.

But just that much grinding with the silicone carbide wheel - perhaps a total of 16 passes - and the gritted wheel was worn out. Slick. No grinding surface left.

The silicone carbide wheel is obviously only good for one or, at the very most, two large blades. Then it must be resurfaced (which sounds like a chore to me!), or replaced.

But they do supply you with a little cannister of silicone carbide, plus instructioins on how to re-surface that wheel. However, as cheap as those wheels are, I would just buy a new one knife or two - IF I were going to continue to use that system.

I'm extremely pleased with the wheels, and will probably use them on my Persian Fighter also.

Thanks again for all your help!

Gene

Hey Jerry, that wouldn't be some ne'er do well maker out in the islands that you were referring to was it?? :p

I've been really happy with the Norax edges that I've been producing lately. Like Jerry said, I start with the x100 and then progress to the x5 for a nice shiny wire edge. Then a very light buff or strop on a leather belt and it's good to go! It seems like the smoother the edge the better it cuts which makes perfect sense from a friction standpoint.

Actually it's another ne'er do well in Tennessee.

Not only does that smooth edge cut well, but I think it lasts longer. The rough finished edges that some people like, cut like micro-serrations. The problem with that is that the points on those micro-serrations go away pretty quickly and you're left with a very dull blade. Further, the fine-finished edge resists micro-chipping better IMO.

Craig,
This was also posted as a separate thread a couple of weeks ago when we discussed differential heat treatment for different parts of the blade as an alternative method of dealing with strength vs cutting profile issue.

As it turns out, the idea works for carbon steels (which was what I was referring to) but clearly is different for stainless and high alloy steels which don't have the "linear" properties of carbon steels (ie.- hard = brittle, softer = tougher).

But yes, it seems to work on my carbon steel blades. I use O-1 almost exclusively, and the technique works well for fine tipped blades. I temper to a bright blue.

Cheers.