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JamesR

Round Knife Purchase Hesitation

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I have been putting off purchasing a round knife.

The sharpening issue has me wondering.

I am not unfamiliar with sharpening woodworking tools (with jigs!)

Round knives do not look to jig-friendly.

Stropping the blade does not concern me, its restoring the edge down the road.

It seems that even if you could put the blade in a jig to hold it at the proper angle the handle might get in the way. Also the convex profile seems to defy any jig that I can think of. Everything I have seen or read suggests the whole thing is a free hand affair.

Any good advice on uniformly restoring the edge of a round knife?

Thanks in advance.

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Al Stohlman's book on leatherworking tools has the how to in it. Not hard to do. Best advice get a good one from the start and it will not require much sharpening to begin with. If you can't see yourself getting a really good one for the price like one from Knipschnider, check in with Bruce Johnson. He has zillions of good used ones to fit any hand, at reasonable prices. Give him a call and he will help you pick one out, great guy to do business with, hell he even is a great guy to be friends with, I've only talked to him on the phone, but; puts you right at ease as if you grew up knowing him.

Bob.

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It does not have to be a free hand affair. I made this jig and it works really well.

http://andersenleather.blogspot.dk/2015/05/round-knife-sharpening-jig.html?q=jig

This is version 1. I am currently working on a much smaller and better version.

It is hard to sharpen a knife free hand.. especially a round knife. Don't let anybody fool you. Simply reading some instructions will not even get you halfway there. It takes hours an hours of practice and if you are lucky you will end up with a knife that is relatively sharp. With a proper jig you will get the ideal edge so much faster.

Edited by jonasbo

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Depending on what kind of tools you have readily available...

I'm using a wet grinder and depending on the round knife, I just sharpen it free hand, but there are some jigs you can use or make one yourself that will imitate the radius of your round knife. This is the kind I'm using https://www.google.com/search?q=scheppach+nsm+200&client=ubuntu&espv=2&biw=1314&bih=818&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjc4LCZyKvJAhWDRw8KHQQCDvoQ_AUIBygC#tbm=isch&q=scheppach+wet+grinder but there are others like the Tormek etc. which are pretty much the same. Sharpening is so simple with them and stropping even easier with the attached leather wheel.

If the knife is something out of shape I usually use a compass to mark the correct shape and go from there. I have to ad that I'm sharpening woodworking tools for over 28 years now and it has become natural so a jig may be very helpful for beginners. Based on the knife jig #60 for the Scheppach a round knife should easily be sharpened without loosing the correct angle.

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jonasbo,

Thank you for posting that jig. I will be taking a close look at those photos. Please post the next version when it is ready.

Thor,

Thank you too. I use a Makita horizontal wet grinder for my woodworking tools. I am not sure I would have the clearance to use it on a round knife though. I can see how a jig would maintain the angle but am not sure how you get the convex edge without rocking the blade?

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If you invest in a quality blade and do not intend on entering a hatchet throwing competition. you shouldn't need to regrind the edge. stropping is all you need unless you plan on doing some higher grit clean up.

Good luck

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A convex edge is most easily attained through "slack belt" sharpening. Or, having enough give in the belt that the pressure from the blade creates the radius (I know.... it's a complex radius).

Though, I must admit.....it's just easier to buy once, cry once.

One of the makers listed above was misspelled- it's Knipschield (knipknives.com)

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jonasbo,

Thank you for posting that jig. I will be taking a close look at those photos. Please post the next version when it is ready.

Thor,

Thank you too. I use a Makita horizontal wet grinder for my woodworking tools. I am not sure I would have the clearance to use it on a round knife though. I can see how a jig would maintain the angle but am not sure how you get the convex edge without rocking the blade?

The new jig is made: http://andersenleather.blogspot.dk/2016/02/round-knife-sharpening-jig-version-2.html

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The convex edge is attainable with a slack belt grinder with a short distance between the wheels, or many times with a soft platten. Andersenleather has a great design for the power challenged. I have seen the basic concept somewhere else, but not the same, it kind of looked like an elliptical treadmill when in use. There is no necessity for a convex edge. We flat grind the edges as the user is going to mess-up a convex or turn it into a flat grind or hollow grind so the convex is something we consider an exercise in futility. The flat grind is easier to find the bevel and establish a secondary bevel, which always happens when a flat grind is honed. So if you make a wedge of say 10°, and put the blade flat against it and present the edge to a moving abrasive, grind both sides and you have a 20° included angle which is where we generally sharpen head knives. Make the wedge small enough so the handle clears, and if you want, countersink a couple of Neodymium magnets in the surface to pull the blade into the wedge. Use the wedge as a guide on a stone, you will soon get the feel of what 10° or 15° is, but in our shop, we have so many things that sharpen at so many different angles, on so many different grinding machines (10), that we have to use jigs; add to that, we have stones up the wazoo too. If we freehanded, how do you tell the difference between 10° and 15° on each machine?

Now, lets bring into the equation the fact that all head and round knives are not round. This adds other difficulties that just will make life difficult.

Art

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I don't have one of his Head Knives, but I do have several of his other leather knives. Fit and finish is excellent, and his knives do cut, as evidenced by a "red" moment or two (before I gave them their due respect).

Art

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I have one and it is the most used tool I have, bar none.

Bob

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Skiving Knife, Bevel Point, and Curved Detail. They came Bleeding Sharp (testimonial).

Art

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What RPM does one use to polish the blade of a round knife?

Chris

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I have 3 of Terry Knipscheild (sp?) knives- head/round knife, skiver and pointed knife.

Have had 2 of them for 3-4 years now- I stop them prior to using them each time to keep them razor sharp- and still have not had to have them re-ground. I ususally am cutting 5/6 or 8/10 oz veg tan, latigo or bison.

don't hold off getting a quality round knife because of the concern about having to have it reground

RMR

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What RPM does one use to polish the blade of a round knife?

Chris

When I use belts, I run them about 500 ft/min for grinding up to 6000 grit or or higher. When buffing, I run 10 inch felt wheels at 1750 to 1800 rpm and sewn wheels at 35 to 3600 rpm, which is 4581 and 9162 ft/min respectively. You can actually do everything from cutting to final polish on felt wheels with the appropriate compounds, even at 3600 rpm and 10 inch wheels. Just watch the heat.

Art

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