How Sharp Is Sharp?

[x101airborne]

I have been pulling out all the old tools I purchased used a year ago and found a head knife that was covered in light rust. I got some 800 grit paper and took the rust off to find it is a C.S. Osbourne knife but it needed sharpened badly. Ran it through the stones then the strops and musta had some success cause when I went to touch the edge with my thumb, I took about 8 layers of callous off without even knowing. It goes through saddle leather like it isn't there.

Looking at how to sharpen other tools, I see I need some more stones and rods to do different tools. Question posed to you good people is how often do you sharpen different tools and how sharp do you want them? I think I got a little over-zealous with this head knife, but my Father is an ex-butcher and razor sharp to him is when he goes back to the stone. I think the first atom was split with a processing knife from a slaughter house.

[thefanninator]

I'm not a good sharpener and don' sharpen things enough but I think you should be able to shave with a blade. I end up using replaceable blades most of the time.

I see that flintknapping is an interest of yours so I'm going to guess you've done some archery. To file my broadheads I would put a burr on and take the burr off until they could shave. Then hit them with some jewelers rouge or polishing compound on a strop.

I've been working on sharpening my awl. There are plenty of videos out there on youtube.

[x101airborne]

Flintknapping is a hobby, but I am uneducated about it and it is a hard skill to pick up without some hands / eyes on help and mostly so far I have made some sharp gravel. I got some obsidian from a friends rock garden and that is another thing to try to work with. I have done some archery but gave up on it. I just don't have time. I used to use Muzzy broadheads and just got the replacement blades. Never tried sharpening them. Any of my experience sharpening is on knives. We do all our own slaughtering be it beef, pork, deer, etc. Trying to work a dull knife makes the meat look like heck and is more dangerous than using a proper sharp one.

As for the head knife, I would not try shaving with it. It sliced the callous on my thumb clean. It did not try to slide on the skin at all.

Do any of yall sharpen your skivers / gougers? I saw a video on it, but I am sure that is another skill to master. My edgers are so dull all they do is rip at the edge, not cut.

[rickdroid]

I sharpen every tool i have that is used for cutting or edging or skiving. Much like your example of using a dull knife in a slaughter house, using dull tools working with leather is dangerous and produces lousey results.

How sharp do i want them, as sharp as I can get them. For me, the sharper the tool the better results i get and the least effort i have to put in to get those results.

As far as the process, i use a stone only initially, after that i maintain the tools on a strop. The only time i would again use a stone would be if i ding the edge and need to rework it.

It sounds like you have your head knife well sharpened, and that is one of the harder tools to get a really good edge on.

To me the hardest tools to sharpen are edgers. Taking the burr off of the inside of the v is more time consuming than any other tool i work on. Skivers are probably the easiest.

Hope this helps.

rick

[Art]

Sharp is simply sharp enough for the task. What good is a razor sharp butcher knife if the edge is set back by a bone or chainmail glove? Sharp is a good polished facet up to the intersection of the facets or more commonly, the edge. More importantly, how much metal do you need behind the edge to provide some durability. Knife edge profiles are always a tradeoff.

That being said, sharpening is a machining operation. The deliberate and controlled removal of material. Where two flat planes meet, you have an edge, an almost non dimensional line at the intersection. We all strive to attain and maintain this edge. With a head knife, I would say it can never be too sharp, although some do push the envelope as far as angle goes (I like an included angle of 25 degrees for almost any hand type tool). A head knife is dull when you can hear it cut (sounds like tearing).

Since nobody does enough of it, we tend to talk about it a lot on this forum.

Art

[electrathon]

My gauge is if you can not dry shave the hairs off your arm, it is not sharp enough.

[Art]

My gauge is if you can not dry shave the hairs off your arm, it is not sharp enough.

And you can make a planer blade or an ax do that, even at some pretty steep angles. I've been cut by 90° lathe bits and circular saw blades a time or two.

Art

[x101airborne]

Thank yall. That is some of the information I was looking for. If it wont shave, it is too dull. When you can hear the leather being cut, it is too dull. Sounds like I actually have this one to just a good working edge. Now maintaining it may be a different story, but none of my butcher knives "sing" when they come off the strop, so I will lay a bet this one is some superior steel.

Now I just have to figure out sharpening the gouges, punches and what not. I am sure what I bought are mostly good tools, this guy just didn't do any sharpening. A little maintenance and I should be right as rain.

[TinkerTailor]

If ya have to ask, its probably not sharp enough. You won't regret it being sharper, whatever it is. Make sheaths for everything, to keep them sharp. Buy band-aids.

[Art]

If ya have to ask, its probably not sharp enough. You won't regret it being sharper, whatever it is. Make sheaths for everything, to keep them sharp. Buy band-aids.

Sheaths do not keep knives sharp, they do however cut down on band-aid consumption.

Art

[SmokeyPoint]

My $.02 - Pick up Al Stohlman's book Leather Craft Tools, How to use them, How to sharpen them. It covers methods for sharpening various actual leather crafting tools.

And if you're not happy with your over-sharpened head knife, ship it to me. I'll dull it up a bit and ship it back for you.

Edited December 31, 2015 by SmokeyPoint

[TinkerTailor]

Sheaths do not keep knives sharp, they do however cut down on band-aid consumption.

Art

The do if they prevent tools from banging together in the drawer........Or sticking into the cement floor.....

[club49]

Check out the web site Guns&Knives, Them Guys and Gails really get into it. I ordered a few stones and a DVD. The DVD is made by Murray Carter. He is a 7th generation Yoshimoto bladesmith. He takes you through the whole process of freehand sharpening. He has two DVDs out that I know of. I got the one called Blade Sharpening Fundamentals, there is a more advanced one. After watching the DVD, I realized how little I knew about sharpening. There is 2 hours and 51 minutes of information on how to sharpen blades. It is a good refrence tool.

Jim

[Colt W Knight]

I too use the if it won't shave it's not sharp enough metric.

[club49]

If you read my post above please don't make the same mistake I made. The stone that I ordered from Murray Carter turned out to be bad news. I used it tops 6 times. It started to flake off on the side of the stone. The DVD is very good, not the stone. He told me that I was to rough on it.That I must have been using something hard on it. He would refurbish it but would not give me a new stone. I guess steal is something hard. This guy didn't want to hear about it. I sent him a photo, the stone was so new you can still see the writing on it.

 

Jim