Honing cutters

[ken hatch]

Ok I'm at a loss, my Cardio Ablation isn't until the 17th. and my energy level is such doing much more than sharpening a chisel kicks my butt. That doesn't stop me from thinking and an area I've been thinking about is why do we do the thing that we do when sharpening our cutting tools.

I work from one given, the smoother the cutting edge the longer the edge will stay working sharp. But if length of time isn't a factor how smooth does the edge need to be to work and leave a usable surface. It kinda depends on what you call a usable surface.

I did a quick and dirty test using a post-war Marples 3/4 chisel that I hollow ground to a 25* bevel on the Tormek, mostly because if I wanted to extend the test I could return the chisel to the same condition easily.

Here is the chisel:

chiselA.jpg


And the bevel off the Tormek:

chiselB.jpg

I tested four basic conditions: Honed on a Medium India and then stropped on oiled leather. After testing the cut then stropping on leather with compound. Honed on a Wachita follow by the same stropping protocol. Honed on a Black Arkansas and same stropping protocol. And last honed on a JNat finishing stone with out stropping. BTW, the difference between stropping on oiled leather vs. leather with compound was only in the shine.

Again all subjective but the subjective results were as I expected. The effort to pare was close to the same for all stones and stropping protocols. In a blind test I doubt I could have picked one from another. A tactile feel of the surfaces would have been difficult but there were some very slight difference in feel between the cuts but you would have to work at it to identify which was the smoother.

A visual inspection using a 10X loupe showed a clear progression from the India to the Black Arkansas with no difference between the Arkansas and the JNat.

Bottom line, if longevity isn't a factor, the India and a strop gives a good enough working edge for almost any task. I'll still go to the Black Arkansas or the JNat for final honing but my guess is it isn't necessary for most jobs.


ken

[Nicholas Lawrence]

I have been thinking there is not that much difference between my “hard” arkansas followed by the strop and using the black. Interesting.

[ken hatch]

I have been thinking there is not that much difference between my “hard” arkansas followed by the strop and using the black. Interesting.

Nicholas,

I doubt there is much difference on the first cut. Where I expect there is a difference is on later cuts. All else equal the cutting edge should break down along the scratches, the deeper and sharper the scratches are the easier and quicker the edge dulls and breaks down. I'm sure someone with better test equipment than my calibrated hands and eyes could show that but I have to take it on faith.

ken

[ken hatch]

BTW, for the "shine" folks, I just honed on a Shapton 15000 stone with out using a strop to finish. I will say the bevel's shine is impressive but shine doesn't cut wood. The effort to pare and the surface left was no different than that of the Black Arkansas or the JNat, but the shine sure was pretty.

ken

[Jim Koepke]

One place where the difference of the smoothness of an edge shows is on end grain.

Before & After.jpg

Little lines will show up where the edge is compromised.

jtk

[James Pallas]

In the 70s I used a fine carborundum and plain strop. I than graduated to a fine carborundum, fine India and strop with compound. Late 70s a lot of water stone talk and DMT around. I bought both. DMT black, blue, red. King 800, 1200, S-3. Used the Kings a bit still have them in the original boxes. Used the DMTs and strop with compound for years. Bought DMT plates to extra extra fine and still use them. Also bought Sigma powers to 13000. Used them some. Now stored with the Kings in their original boxes. Current use is medium India, fine India, trans ark, strop with gold or plain strop for Carving, chisels. DMT plates for PMV 11 plane irons and strop. Works for me. I have a small Washita 2x4 I use for pocket knives. I guess I could use Ken’s words and say I’ve had a few frogs around.

[Derek Cohen]

I did a quick and dirty test using a post-war Marples 3/4 chisel that I hollow ground to a 25* bevel on the Tormek, mostly because if I wanted to extend the test I could return the chisel to the same condition easily.

[snip]

I tested four basic conditions: Honed on a Medium India and then stropped on oiled leather. After testing the cut then stropping on leather with compound. Honed on a Wachita follow by the same stropping protocol. Honed on a Black Arkansas and same stropping protocol. And last honed on a JNat finishing stone with out stropping. BTW, the difference between stropping on oiled leather vs. leather with compound was only in the shine.

Again all subjective but the subjective results were as I expected. The effort to pare was close to the same for all stones and stropping protocols. In a blind test I doubt I could have picked one from another. A tactile feel of the surfaces would have been difficult but there were some very slight difference in feel between the cuts but you would have to work at it to identify which was the smoother.

A visual inspection using a 10X loupe showed a clear progression from the India to the Black Arkansas with no difference between the Arkansas and the JNat.

Ken, did you grind to the edge of the blade? If so, then it would not be difficult to create a working edge on just about any media since the area to be honed is so small. And coming off the Tormek, the edge is straight and less work is needed again.

The steel you are honing is quite simple O1, easiest of them all.

If you really want to experience the difference between media, then hone full bevels. Also try different steels.

Regards from Perth

Derek

[ken hatch]

One place where the difference of the smoothness of an edge shows is on end grain.

Before & After.jpg

Little lines will show up where the edge is compromised.

jtk

Jim,

You are correct and I expect when working end grain is where the longevity of using higher grit stones/smoother cutting edge would come into effect.

ken

[ken hatch]

In the 70s I used a fine carborundum and plain strop. I than graduated to a fine carborundum, fine India and strop with compound. Late 70s a lot of water stone talk and DMT around. I bought both. DMT black, blue, red. King 800, 1200, S-3. Used the Kings a bit still have them in the original boxes. Used the DMTs and strop with compound for years. Bought DMT plates to extra extra fine and still use them. Also bought Sigma powers to 13000. Used them some. Now stored with the Kings in their original boxes. Current use is medium India, fine India, trans ark, strop with gold or plain strop for Carving, chisels. DMT plates for PMV 11 plane irons and strop. Works for me. I have a small Washita 2x4 I use for pocket knives. I guess I could use Ken’s words and say I’ve had a few frogs around.

James,

I love me some frogs. It is always interesting to try different things but kinda like you I almost always come back the my standard set up. Usually an India for grinding and a natural stone for honing followed by a natural stone for polishing. With oil stones I strop, with JNats I do not.

ken

[ken hatch]

Ken, did you grind to the edge of the blade? If so, then it would not be difficult to create a working edge on just about any media since the area to be honed is so small. And coming off the Tormek, the edge is straight and less work is needed again.

The steel you are honing is quite simple O1, easiest of them all.

If you really want to experience the difference between media, then hone full bevels. Also try different steels.

Regards from Perth

Derek

Derek,

I wasn't interested in comparing steel or even how effective/fast the stones were. I wanted to see what differences there were in the cutting edge from a coarse grit stone vs. finer grit stones. What I found was; there isn't much. i do expect as the cutter is used the finer grit edge would give an acceptable finish longer than the cutter from a coarse stone but that was beyond my ability to test.

BTW, your first statement is correct "...it would not be difficult to create a working edge on just about any media...". My take away is if I didn't mind doing a quick grind/hone and strop on the India often it could be as effective as a longer hone and polish on natural stones. Would I do it? Probably not but I expect that's how the old guys worked.

ken



ken

[Derek Cohen]

Ken, perhaps I did not explain myself well. You relegated my main message to a BTW, and focussed instead on my throw away.

I was attempting to say that, if you are honing on a full hollow grind (to the edge, which results in the minimum of steel to hone), it is going to minimise any differences in sharpening media.

Regards from Perth

Derek

[James Pallas]

[QUOTE=ken hatch;2988692]Derek,

I wasn't interested in comparing steel or even how effective/fast the stones were. I wanted to see what differences there were in the cutting edge from a coarse grit stone vs. finer grit stones. What I found was; there isn't much. i do expect as the cutter is used the finer grit edge would give an acceptable finish longer than the cutter from a coarse stone but that was beyond my ability to test.

BTW, your first statement is correct "...it would not be difficult to create a working edge on just about any media...". My take away is if I didn't mind doing a quick grind/hone and strop on the India often it could be as effective as a longer hone and polish on natural stones. Would I do it? Probably not but I expect that's how the old guys worked.

ken
I believe I just do things out of habit. A strop is always in reach. If I pick out a chisel it’s almost automatic to give it a couple of rubs on a strop same with carving tools. I think of how barbers do with their razors. They almost always give the razor a little strop on the leather. Sometimes they will hit the linen side sometimes not. A butcher will hit knife to a steel. Sometimes when I’m thinking about my next move I’ll find myself putting edge to strop, helps me think. It’s like sticking a pencil behind your ear or your six inch scale in your shirt pocket. I can’t work with a shirt without a pocket. Unnerving it is, upsets my whole routine Lol

[mike stenson]

Derek,
My take away is if I didn't mind doing a quick grind/hone and strop on the India often it could be as effective as a longer hone and polish on natural stones. Would I do it? Probably not but I expect that's how the old guys worked.

It's how the old guys I was around as a kid worked. Yes, you do have to 'touch up' more often. I'm not sure, in aggregate, if you gain or lose time in either manner.

[ken hatch]

[QUOTE=James Pallas;2988721]

Derek,

I wasn't interested in comparing steel or even how effective/fast the stones were. I wanted to see what differences there were in the cutting edge from a coarse grit stone vs. finer grit stones. What I found was; there isn't much. i do expect as the cutter is used the finer grit edge would give an acceptable finish longer than the cutter from a coarse stone but that was beyond my ability to test.

BTW, your first statement is correct "...it would not be difficult to create a working edge on just about any media...". My take away is if I didn't mind doing a quick grind/hone and strop on the India often it could be as effective as a longer hone and polish on natural stones. Would I do it? Probably not but I expect that's how the old guys worked.

ken
I believe I just do things out of habit. A strop is always in reach. If I pick out a chisel it’s almost automatic to give it a couple of rubs on a strop same with carving tools. I think of how barbers do with their razors. They almost always give the razor a little strop on the leather. Sometimes they will hit the linen side sometimes not. A butcher will hit knife to a steel. Sometimes when I’m thinking about my next move I’ll find myself putting edge to strop, helps me think. It’s like sticking a pencil behind your ear or your six inch scale in your shirt pocket. I can’t work with a shirt without a pocket. Unnerving it is, upsets my whole routine Lol

James,

I like your style . When I can't think of what to do next I will usually hit the stones.

ken

[Rafael Herrera]

Ken, just thinking about what you are doing I would say that giving the chisel a hollow ground you are thinning the edge you need to sharpen. Perhaps that's why all your edges feel the same, you can't get anything better than that quasi-knife edge you're giving the chisel. I also would think that that edge will not last very long or will be fragile since you're thinning the tip of the blade. Would you consider sharpening the chisel's whole bevel and then re-test? How would a 25* or a 30* flat or lightly bellied bevel feel?

Rafael

Off topic, I love the edge I get on a new set of Ashley Iles bench chisels I just got, and the 1/32" thin sides. Sharpening the whole bevel was a pleasure.