How does everyone do their final sharpening?

Huntsman Knife Co. LLC.

Huntsman Knife Co. LLC.

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Knifemaker / Craftsman / Service Provider
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I'm curious to see how you guys place the final edge on your knives and how I can improve my method.

Sorry I don't have a picture of my setup but I do all my final edges on my KMG. For hunting knives and slicers I try to get final edge thickness before sharpening down to .010. For tomahawks I tend to leave a final edge thickness of .025 but may go thicker or thinner depending on the design. I use my rotary platen at low speeds and freehand cut the final edge. I aim for about 15 degrees per side but there's obviously some slop since I'm not sharpening with a jig. For most knives I set my initial bevel with a sharp 220 and then finish with a fresh 320. I do all of my final edges wet with a sprayer directly on the edge to eliminate heat build up. Before I started using water I burnt a couple edges even with fresh belts and slow speeds :eek:

From there I usually go to the paper wheels and strop the edge.

With my method I tend to get good, sharp edges that cut well but I have some worries.
1.) Since I freehand my angles are not perfect and it bugs me, especially around the tip I tend to open up the edge too much. I'd like to see how guys with jigs sharpen.
2.) Though paper wheels leave a really sharp edge, I don't think edges done with paper wheels stay sharp as long as edges sharpened by hand. I've never done a direct comparison but I have my suspicions.

So how do you guys set your final edges?
 
I usually finish with a 6 or 800 grit belt and then the leather belt.
If I want a more toothy edge I go from 400 grit to leather.
I get great edges that work for me without going overboard.
 
I use almost the exact same method as you do. My final grit is a fresh 320 (anything less, too toothy, anything more, not toothy enough). The only differences are that I like a bit more of a convex edge, so I go slack belt, and for the stropping step, I use a hard buff loaded with compound instead of a paper wheel. I found that the hard buff produces a slightly less sharp, but slightly more durable edge than the paper wheel, for me at least.

It's the fastest and best quality way I've found to sharpen as of yet. I can get a shaving sharp edge from blunt as fast as 2-3 minutes, but usually more like 5-10. As I'm sharpening knives I've finished, I often wonder if I'd be better off just doing knife and scissor sharpening :D
 
I always sharpen knives freehand on shapton glass stones or natural water stones. It's fun to sharpen freehand and is just something I've always done.
 
on hunters I will progress up through 600 grit belt on the grinder and then hit it on a hard buff. kitchen blades I will start on the grinder and then do by hand on water stones up through 8000 and then strop.
 
I go from 240 to a 400 grit on a belt at low speed.Then I go by hand on sandpaper from 600 to 800 to 1200 on a soft cover book. Last step is a leather strop loaded with white compound. I like a smooth convex edge. This edge may not be toothy enough for some but it seems to last the longest for me.
 
Sharpening on the belt and on paper wheels is ruining the heat treat of the most important part of your knife, namely the first 5-10 microns that comprise the edge. According to Roman Landes' presentations at Ashokan that first couple of microns will get to as high as 2000 degrees from dry abrasion. You will not notice because that heat energy quickly dissipates into the larger mass of the blade.

After Roman's first Ashokan presentation a couple of years ago I started doing my final edge bevel by hand on DMT diamond stones with a water/dish soap coolant/lubricant and found noticeable improvement in sharpness and edge retention

-Page
 
Sunshadow,

Do you think its possible that the edges still get hot even with flood coolant running? I do all my edges completely wet and they don't seem to get hot at all but I've noticed when I grind down pins on my handles wet they still can get hot.

Im also worried that the paper wheel creates too much heat. I guess on the bright side a sharpening or two by the customer should expose fresh steel but I'd like to send my knives with the best edge possible.
 
For the chef's knives, 600-400 for the finish and then guided DMT stones up to 3 microns (extra extra fine stone/tan). I strop on damp news print as a final.

I'll sharpen both sides with an equal number of strokes, so I get the cutting edge dead center on the knife. Whatever minimal burr I develop, I'll break off with a few passes on a piece of cork or the edge of a old waterstone. i'll repeat the sharpening process using progressively finer stones until I net a non-toothy edge, using a 60x loupe to confirm. It's a pain in the ass but, it worth it knowing that your giving someone the sharpest knife they've ever owned.
 
Last edited:
KalEl said:
Sunshadow,

Do you think its possible that the edges still get hot even with flood coolant running? I do all my edges completely wet and they don't seem to get hot at all but I've noticed when I grind down pins on my handles wet they still can get hot.

Im also worried that the paper wheel creates too much heat. I guess on the bright side a sharpening or two by the customer should expose fresh steel but I'd like to send my knives with the best edge possible.
Click to expand...


With flood coolant and a low SFM you should be alright as long as the coolant is actually making it to the area the abrasion is happening. Higher surface speeds will run the risk of exceeding the specific heat of the small volume of coolant in contact with the critical areas. Paper wheels are just a bad idea, they build up heat and round over the edge. They are a quick and dirty solution for allowing people who do not know how to sharpen to put a mediocre edge on something. You are unlikely to get anything to the point where it will sever a free hanging human hair with a paper wheel, however diamond stones followed by an 8000 grit water stone followed by a rigid backed strop will do exactly that if the geometry of the blade is good and the edge not overheated

-Page
 
I use diafolds from DMT
(gray 120) Black-blue, red-green. I´ve stropped after that and also used a Belgian waterstone before stropping. The latter is app. 6000/8000gritt. Sharp!
 
I set the primary edge with a 240 grit, followed by 400 grit and run the belt grinder at a very slow speed on the 10 inch smooth contact wheel. Then I remove the burr and bring up the final edge using ceramic V rods until the edge is popping hair off my arm. The edge is slightly toothy. My customers like the edge and usually bring in a whole bunch of knives for sharpening afterwards.
 
Lately I've really been liking the 60 grit until there's a wire, then buff with a laminated leather wheel and green compound then slide the edge along a piece of wood a couple of times to clean it up. Hair popping sharp and nice tooth. I think I'm going to sharpen everything like that from now on.
 
220, 1000, 6000 grit waterstones after the edge is ground thin and convexed. Sometimes I stop on an extra fine DMT plate. Depends on what I anticipate the knife being used for.

I've been using the waterstones the past few months and the edge seems sharper and lasts longer versus just using belts and a buffer. Edge retention was very noticeable.

Just my $0.02
 
Paperwheels, then strop on leather loaded with MAAS metal polish. Sometimes strop on leather loaded with Veritas Green in between, depending on the paperwheel edge.
 
Depending on the knife, I use one of three methods:
1) a worn 320 or 400 grit belt followed by buffing wheel with green rouge
2) lansky system
3) DMT stones to form the edge and spyderco ceramic stones to refine it

- Chris
 
If you really want the skinny from some serious rock star sharpeners spend a little time reading threads in the maintenance forum. I'm a hobby level sharpener and I've learned an incredible amount about various sharpening techniques. There are a few threads on initial sharpening of blanks and freshly made knives. A number of guys there have spent many years and thousands of dollars on learning the art of sharpening.

For knife making stuff and metallurgy information I come here, for diversified and extensive knowledge on all things regarding applying a ridiculous edge I go to maintenance. The two go hand in hand, yet I see very little cross referencing of members between the forums.

I promise that it'll benefit your knife making.
 
I start the edge with a 220 then use Smiths diamond stones at a 25 degree angle, take down to an arkansas stone, then finish by stroping on leather. It always gets a knife hair popping sharp, and produces a durable edge. Theres probably a better way, but this works for me.
 
I don't dispute that you can achieve almost supernatural sharpness with the proper techniques, but my gut tells me that my machine-finished shaving sharp edge is sufficient for the abuses of most average customers (working customers, on working knives). A super fine edge will be destroyed to worse than a machine finished edge within the first couple uses, at least from what I've seen.

It's heartbreaking to spend all that time honing an award winning edge only to have someone turn around and use it on a ceramic plate to cut their steak.


edit: I think in the hands of an experienced knife user/maker/collector, that is less likely to do horrible, terrible things to the edge, a finely honed edge makes a lot more sense.
 
I spend more time getting the geometry right than the the final sharpening. Geometry cuts.

I am on the same page as... er, Page. Lubricated, hand sharpening for the final edge.

That said, I sharpen knives for local kitchens and amateur chefs. Depending on the expectations, I am not above using a 300grt belt, followed by a few passes on a slotted paper wheel. At times, I have 70+ knives to sharpen.
 
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