Chisel Sharpening - One Way or Both Directions?

[fritz eng]

Wondering if only drawing the chisel towards you, as opposed to pulling and pushing the chisel on a sharpening stone or diamond plate will give a less ragged tip edge. I thought I saw D. Charlesworth only drawing a chisel towards him when sharpening. Any thoughts?

[Tom M King]

I don't think it matters. My pressure is on the push, and has always been, except when pulling back on diamond lapping film, because pushing with cut the film. To me, there is no feel for what it's doing, when pulling back. I never bother to feel for a burr, because I can feel what's been done, but can't do that when pulling.

[Rafael Herrera]

Depends on your media. If using hard media, it doesn't matter, provided you don't tend to round the bevel, pick a direction. On softer media, you may gouge the stone if pushing the edge against the stone, pull the tool towards you.

Keep in mind that towards the final stages of honing you need more control and pulling is easier.

[Robert Hazelwood]

On most stones you can go both directions. Exceptions being very soft media or sandpaper, where its better to pull only to avoid tearing paper or gouging the stone.

I go both directions while trying to raise a burr and polish. But once finished with that, I do a few passes with very light pressure going forward only, alternating each stroke between bevel and back. This is to weaken remove the burr- forward strokes do this a little better.

[steven c newman]

Then, there are some who go side to side.....

Oil stones: It goes back and forward....and sometimes side-to-side ( on the wider ones)

Wet-n-Dry Sandpaper up to 2500 grit: Pull it back...as pushing will slice the paper.

Strop: Pull it back

Unicorn: Let the wheel do the work.

[Jim Koepke]

Good morning Fritz, this is the kind of question to prove a thousand people can have two thousand answers to the same question.

As has already been mentioned about using film or paper abrasives there is a tendency for them to become torn using a push stroke. The use of sandpaper has recently been given the name of the "Scary Sharp" method.

In my experience there is more of a burr formed on a pull stroke. A co-worker demonstrated this to another co-worker using a piece of plastic and a file. Though when a burr is to be removed, pull strokes alternating between one side and the other of a blade are the preferred way to remove the burr.

This gets into the minute physical details of sharpening.

What is happening to the metal (swarf) that is being removed when sharpening a blade?

Is it helping or hindering the effort?

The theory with water stones is the swarf combines with the abrasive particles to help polish the blade.

On abrasive sheets the swarf loads up between the abrasive particles and prevents them from working as effectively.

So the two statements above are how two answers can be both right to the same question.

jtk

[Tom Bender]

I agree with Tom, 'no feel when pulling' when free handing. When pushing it's easy to control the angle by approaching that angle where it starts to dig into the stone.

[Robert Engel]

I go both ways except for 1/4" or narrower chisels. I skew them slightly.

I sharpen freehand, probably somewhat differernt if you're using a jig.

But, it never hurts to do the last few strokes pulling.

[mike stenson]

I have to use a jig on 1/4" or narrower chisels, I've never been able to not dub them otherwise. Rather than fight it, I just gave up and use a jig

Yes, with the jig I pull. So for me, it is different.

[Luke Dupont]

You forget "all directions."

I'm a fan of little circles working up and down the stone. This seems to aid cutting at times when using Arkansas stones, especially if the oil is a bit too thick and the contact surface wide, thus suspending the tool from the stone a bit too much.

I use this stroke with knives as well, to good effect. It may be my imagination, but I think it also helps with reducing the burr and achieving a sharper final product when the scratches are going in all directions. Again, maybe just my imagination, though.

[Clark Magnuson]

CBN grinder 20210402_154531.jpg

I modified a grinder to run CNB discs for sharpening chisels.
I cut the time to restore a chisel by hours.

[Don Dorn]

I do both using free hand, ala Paul Sellers. Once I picked that up, I haven't changed in years. At least for me, it's quick, the sharpest method I've tried and like the "convex" result that comes from "inperfection" Only grind every six or eight sharpenings when the convex hump becomes too much.

[Edward Weber]

I like the CBN discs, I might have to get one.
As for film media tearing while pushing against, that's never been a problem for me.
I use a granite surface plate and abrasive paper. For the angle I use a Veritas MK2.
I wouldn't suggest this method for those who prefer freehand strokes.
Each setup is identical to the previous one, there is little danger of the edge cutting the paper. The only time I've sliced the sandpaper is because of user error.
Just my two cents

[Tom M King]

I use .1, and .5 micron Diamond Lapping Film mounted on a granite surface plate as the final touch. We use several different jigs, including the MK2. After a couple of strokes on that film, if you go forward, the edge is now so sharp that it will cut right down through the film. We only pull back on that now.

I don't have any problem with regular sandpaper tearing on the large granite plate, with jointer knives, or whatever else we sharpen, or lap on that.