Sharpening Carbide Tips

[Russell Neyman]

Was watching a video by a well-known woodturner yesterday, and he said "carbide cutters are made to be disposable and can't be sharpened." Huh? I sharpen mine all the time. I just place them topside down on a fine whetstone and rub them until the edges are crisp. (Wet-and-dry sandpaper does the job, too.) Works fine. Am I the only one?

[Bruce Jones]

Was watching a video by a well-known woodturner yesterday, and he said "carbide cutters are made to be disposable and can't be sharpened." Huh? I sharpen mine all the time. I just place them topside down on a fine whetstone and rub them until the edges are crisp. (Wet-and-dry sandpaper does the job, too.) Works fine. Am I the only one?I use a Diamond sharpening stone to hone mine all the time. https://www.amazon.com/Smiths-DCS4-4-Inch-Diamond-Sharpening/dp/B00009YV6L/ref=sr_1_7?crid=SYXCAXMEZNW6&keywords=diamond+stone+for+knife&qid=1636223781&sprefix=dimond+stone+for+%2Caps%2C164&sr=8-7

[Edward Weber]

When You're "sharpening" those inserts, you're really just honing the flat part of the cutting edge and not the bevel. You need something harder than carbide to make it viable and you will probably don't get them as sharp as they came new.
They are, designed to be disposable. Once dulled, you can do what you like to try and stretch your dollars but between the time and materials needed to hone one plane of the cutting edge, it's not really worth it for some people.
Can you sharpen them, sure, to a point.
Should you bother, that's up to you.

[Russell Neyman]

...you're really just honing the flat part of the cutting edge and not the bevel...you will probably don't get them as sharp as they came new....

I dunno; after working them with a stone for a bit, they work quite well. Obviously, I keep spare tips handy, and I'll agree that the factory edge is better, but only slightly.

[Jeff Jackson]

It all depends on what kind of cutter. The flat ones like the Easy wood tools would be easier to do than the cup style cutters like the Hunter tools.

[Reed Gray]

John Lucas played around with it a bunch, and did some micro photos of the results. You can touch up the flat ones a tiny bit, and hone the top and bevels on a fine diamond hone. The Hunter type cups all would chip out on the edges. Can't remember if the flat ones did or not. I don't think the 1000 grit stones are fine enough to get them back to factory edge. It has always surprised me that the diamond hones seem to stop at 1000 grit while other sharpening systems go up to as high as 10,000....

You do need diamond to take care of carbide.

robo hippy

[Richard Dooling]

You absolutely can sharpen the flat scraper style cutters on a diamond plate and it doesn't take long if you haven't let them get too dull.

I really only use one very much and I have three cutters ready to go in and out of rotation. You're not likely to get back to a factory edge but I don't care. Even brand new these seldom deliver as fine a surface as other tools so I follow up with gouges, negative rake scrapers etc. I just find this tool a convenient to use sometimes and if I had to keep buying new cutters I'd give it away.

DMT list their Extra Fine plate at 9 microns. Different conversion charts I've looked at vary but put that at about 2000 grit. Not as fine as I'd like but it's serviceable for this purpose.

[Russell Neyman]

You absolutely can sharpen the flat scraper style cutters on a diamond plate and it doesn't take long if you haven't let them get too dull. I really only use one very much and I have three cutters ready to go in and out of rotation... Even brand new these seldom deliver as fine a surface as other tools so I follow up with gouges, negative rake scrapers etc...

You and I are of the same mindset. I use these flat-topped carbide cutters occasionally for detail work and tight places, but my "regular" tools -- gouges, mostly -- do most of the heavy lifting. I should have added that, yes, I do use diamond cards to sharpen them very often.

[Edward Weber]

You absolutely can sharpen the flat scraper style cutters on a diamond plate and it doesn't take long if you haven't let them get too dull.

Even brand new these seldom deliver as fine a surface as other tools .


This is a characteristic of carbide. Corner strength is something that is difficult to overcome. Carbide can only be sharpened to a certain point at any given angle before it fails. You're not going to get a razor edge on carbide before the edge fails. The edge you do achieve may last longer but will not start as sharp.

[Kyle Iwamoto]

Good thread. When I read the title, I thought it was Tips on how to sharpen carbides. LOL.
I'm going to add, that all carbide tips (pun) are not equal. I have a mid priced set (not EZ), and the cutters are so so, and I do touch them up. I got a Woodpeckers and that carbide is way way sharper than the mid priced ones.... Have not had to touch that up.

Lastly, how do you sharpen the Hunters? For those of you who do sharpen them. I have several Hunters. I have one of his first or second run of tools. I'd like to "touch them up". Can't figure how to do it and be consistent.

[Randy Heinemann]

If you own a Tormek and Tormek diamond wheels, the gouge jig has an attachment that is designed for resharpening of the Easy Wood type cutter heads. I don't know if it will work with the Hunter type or not and it is designed to work with the round carbide inserts (although I have experimented with the radius cutters with limited success). This method does, in fact, get the inserts razor sharp, but it can only be done about 2-3 times before the cutter doesn't extend beyond the tool's shaft and won't work.

I have honed the flat side on a diamond stone but found the results to be disappointing and the cutter is much less sharp than when new.

[Russell Neyman]

And then there's the elephant in the room for all of you "purists" who say "real woodturners" just throw carbide tips out when they get dull: there are sophisticated systems sold to help us sharpen them!

468500 468501

[Edward Weber]

I say do what you want with them, I just wouldn't use the word "sophisticated" to describe the honing kit.