Stumpy Nubs Video - Do you flat or hollow grind?

[Steve Mathews]

Do you flat or hollow grind your tools and why? The video below makes a compelling case for hollow grinding. I've been doing a combination of the two methods without regard to which method is necessarily better; primarily flat grinding chisels while hollow grinding woodturning gouges. Having just purchased a belt sander I thought to flat grind some gouges to see if I could tell the difference. I was also planning a similar comparison by hollow grinding some chisels.

https://www.youtube.com/watch?v=6oTbMiLn2us

[Edward Weber]

You did just start a sharpening thread, so hang on.

IMO, neither makes a difference in the actual cutting of the wood.
The difference is in the sharpening and re-sharpening.
Much of this depends on the tool being sharpened but to each his own.
I sharpen a flat bevel and haven't had a need to change.

[Steve Mathews]

You did just start a sharpening thread, so hang on.

IMO, neither makes a difference in the actual cutting of the wood.
The difference is in the sharpening and re-sharpening.
Much of this depends on the tool being sharpened but to each his own.
I sharpen a flat bevel and haven't had a need to change.

Ronald Kanne (woodturner) in one of his sharpening videos stated that he can feel the difference between a gouge that is flat versus hollow ground sharpened. His preference is the latter.

[Holmes Anderson]

Ronald Kanne (woodturner) in one of his sharpening videos stated that he can feel the difference between a gouge that is flat versus hollow ground sharpened. His preference is the latter.

The difference is subtle but definitely noticeable with gouges and skews. I don't see any reason to prefer one over the other but if you are accustomed to turning with one type then the other type doesn't feel exactly right.

[Richard Coers]

I've hollow ground for over 50 years.

[Warren Lake]

taught hollow ground by cabinetmakers. One aspect right off the bat is there are two points to rest the bevel on when honing, makes it easy and maintains the same angle.

[Jimmy Harris]

Always flat. But I've bought tools that were hollow ground, and I didn't care enough to change them. I just use them and let them migrate to flat ground over time.

[Edward Weber]

Ronald Kanne (woodturner) in one of his sharpening videos stated that he can feel the difference between a gouge that is flat versus hollow ground sharpened. His preference is the latter.

I can feel the difference too but most turning tools are typically sharpened with a hollow grind (straight off the grinder).
I was referring to chisels and plane irons

[Allan Dozier]

Whatever is faster, I have a hard time finding the time to sharpen. I use my Tormek for almost everything, so hollow.

[Andrew Hughes]

I also hollow grind most everything except my Japanese chisels. They are very easy to sharpen and the steel is very precious.
The carving knives I use are repurposed pocket knives so hollow grinding makes them easier to sharpen on the stones. Just the same principle as plane blades.
Hollow grinding has been taught way before the internet YouTubers were born.
Good Luck

[Carl Beckett]

You did just start a sharpening thread, so hang on.



Sharpening threads remind me of threads about musical instruments. Which sounds better, a $500 guitar or a $5000 guitar?

[Ken Fitzgerald]

Find a method that works for you and use it. Which method is best? Best is subjective. Just a matter of personal opinion.

[Jimmy Harris]

Sharpening threads remind me of threads about musical instruments. Which sounds better, a $500 guitar or a $5000 guitar?
Tone is in the fingers!!!

But really, there's some truth to that, that carries over to what we're talking about. For instance, if you can't sharpen a plane iron by hand very well, but can on a Tormek, then you'll always get better results with a hollow grind. And if your only grinder just has one coarse wheel and you're pretty good with sharpening by hand, or with a jig, you'll always get better results with a flat grind. What matters most in this equation is the user, not the method or tools.

In reality, it's only the last few microns of the edge that matter since they're the only ones doing the cutting. What happens behind that doesn't really affect how the tool works. So hollow vs. flat... it doesn't matter, because neither are part of the cutting edge, unless you're hollow grinding off a very small diameter wheel that significantly affects the angle of the cutting edge. What really matters is your skills with the tools you have available.

[Bert McMahan]

Sharpening threads remind me of threads about musical instruments. Which sounds better, a $500 guitar or a $5000 guitar?

If you ever go for a hike in the woods, make sure to bring a pocket knife. That way, if you get lost, you can take out the knife and start sharpening it. Pretty soon, someone will come along to tell you you're doing it wrong.

[George Speed]

Sharpening threads remind me of threads about musical instruments. Which sounds better, a $500 guitar or a $5000 guitar?

$250 Ibanez,Peavey Valve King amp. lol

[Tom Bussey]

Stumpy is correct, because the length of the side apposite the angle is the same on both methods, if a micro bevel is honed o the steel. An edge straight off the grinder is good enough if you want a lot of slips and like to work your but off. A small bevel does wonders for a cutting edge and one doesn't have to remove much material to freshen up an edge as work progresses. With a flat edge a lot more metal needs to be removed.

It is said that a 25 degree angle is for soft woods and a 30 degree angle is for hard woods. The pattern shop I worked in had their rest set for 27 1/2 degrees because they worked with both soft and hard woods. I was told when in my apprenticeship that 22 1/2 degrees included angle was the prefect cutting angle and since 25 is closer to 22 1/2 than 30 so I sharpen at 25 and not 30.

In reality it makes no difference to me as to how you wish to sharpen. You can do it any way you want, at any angle you want, it is your tool not mine I think Bob Dillan said it best ( don't you understand, it is not my problem).

[Rod Sheridan]

If you ever go for a hike in the woods, make sure to bring a pocket knife. That way, if you get lost, you can take out the knife and start sharpening it. Pretty soon, someone will come along to tell you you're doing it wrong.

Quote of the week, thanks Bert.

Regards, Rod.

[Rick Potter]

Is this a good place to ask if anyone uses the Taylor Tools setup for sharpening chisels with your drill press?

A lousy sharpener wants to know.

PS: Too chicken to actually OPEN a sharpening thread.

[Jimmy Harris]

Is this a good place to ask if anyone uses the Taylor Tools setup for sharpening chisels with your drill press?

A lousy sharpener wants to know.

PS: Too chicken to actually OPEN a sharpening thread.

You'll probably get more replies if you open a new thread for it. I think a lot of people avoid clicking on sharpening threads unless they know there's something specific they can add ahead of time. So putting that in the title might get more eyeballs on your question. And to be honest, I think we've past peak sharpening thread angst. It seems like we're finally starting to come to terms with the idea that it's okay if other people do it differently. The last several I've seen seem to have more warnings about it going off the rails than actual posts trying to push it off the rails.

Personally, no. I've never used that system. But it does look pretty simple to use, assuming you can build the jig accurately and your drill press chuck doesn't wobble or deflect. And set up will take a while, so it won't be quick. Also switching between angles or small chisels and big plane blades might be a hassle. So I personally wouldn't be interested in it. But, if you're having trouble sharpening, it might be worth the tradeoffs.

There are two "secrets" to sharpening that I've discovered. One, use the coarsest stone, sandpaper, whatever, to make the blade sharp. 200-600 grit is a good place to start. Then use the finer grits to smooth and polish the edge. If it's not sharp after the first stone, keep sharpening it until it is. Moving too quickly between the grits is most people's mistake. Then, once you've got it sharp on that coarse grit, you can move through the other grits relatively quickly, because you're not really doing any sharpening, just polishing. Of course, if the blade isn't dull, you don't have to start on the coarsest stone you own. You can start wherever. Sometimes, I'll jump straight to the strop, because that's all it needs. Just make sure you've done all you can with the fist grit before moving on to the next.

The second "secret" is keeping your angle consistent. However you do this doesn't matter. And the angle itself isn't very important. A 27° bevel cuts about like a 31° bevel. Just know that even the tiniest variations in angle during the sharpening process can have great consequences. I have many times had to start over because I accidentally rolled the chisel forward a half degree on a single swipe on my finishing stone.

The Tay Tools sharpening station kind of takes care of both of those issues. The spinning disk makes sharpening fast, so you're not as penalized by starting off on too high of a grit, and thus less likely to move through the grits before you're ready. And the jig keeps the angle consistent. So I could see it being a good solution for a beginner or someone who's had issues in the past.

[Jim Andrew]

I had a great shop teacher who taught us to sharpen a chisel exactly the way stumpy nubs showed it. Then you use a stone with oil to hone the edge. You can also hone it more than once to maintain a sharp edge.

[Wes Grass]

I hollow grind lathe tools ... Metal Lathe tools. Allows for stoning the edges by creating a tiny flat, and multiple touch-ups are possible before going back to the grinder. Eyeball the angle so the bottom edge is a guide for the relief angle. You'll be at the stone all day if they're ground flat.

There was something I needed a female radius ground in for. Surface grinder and radius dresser was pretty much the only option there ... but no way I was going to be able to stone that face anyway. Hand grind and stone the top face instead.

[Randy Heinemann]

I generally end up with flat ground chisels and plane blades because I'm a hand sharpener. For years, I messed around with all sorts of sharpening systems and methods; both with grinders of some sort and hand sharpening. Finally, I realized that even the best systems may have a few downsides for any user so I picked a method, bought the proper stones and a good hand sharpening jig, and now just use those for resharpening.

When I began turning, I realized that, because I already owned a Tormek, they had jigs just made for sharpening gouges and scrapers that made that job exceptionally easy. So, since I already owned the Tormek, I invested in the gouge jig and do almost all of my sharpening tools with the Tormek and jig. However, the Tormek wheels are 10" so the shape of the resulting sharpened area is hollow ground, but very little.

Recently I bought a Rikon grinder, but really mainly use it to reshape an edge or angle. It's just faster and I finish it up by hand sharpening for the chisels and the Tormek for my turning tools.

Another advised to pick a method and just use it. That's good advice. I just found that there are some tools, like turning tools, which can be resharpened easire another way. So, now I'm more tool specific with the method. The only thing that gets you sharper tools is to practice over and over again.