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Purchased an HD digital microscope and though I'd show the preliminary results.

I sharpened an O1 steel blade and this is what I came up with, honing with a Shapton 5,000, then polishing with a Naniwa 10,000/1.0 micron/0.3 micron lapping film.

I followed that with a light stropping on untreated leather back and front.

This edge produced consistent 0.12 thou shavings, first in in Obeche for setting up with my L-N 62, and then in hard Maple.

First pic is microbevel after final honing

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Second is the back of the iron after final honing and stropping, showing a slight round over of the final edge following stropping.
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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Wow! Have you seen the Japanese competition where they make onion skin thin shavings from a ~3 meter long wide board? I'll have to see if I can find the link.

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Measure Twice,

Karl Borum

Yes, seen a few of them.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

What does a fine edge look like after a couple of shavings? Does it chew up the edge?

Shaving Competition
https://www.facebook.com/fossbytes/vide ... 442773385/

_________________
Measure Twice,

Karl Borum

I expect it will be. I'll post a pic tomorrow after I get the scope charged up again.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

We had a Japanese woodworker do a presentation at our woodworking group. They spend, according to him, one year of their apprenticeship on sharpening by hand. He explained some competitions they had where the plane was dragged with a string producing very long, gossamer shavings. He passed around a very expensive and quite thick (seem to remember 3/16" to 1/4" or more thick, for a look) plane blade. I did my usual, very gingerly, test with my thumb on the blade for sharpness and immediately cut my thumb. Yikes! Never felt anything that sharp before.

Interested in seeing more on this. I just wish I could land on a practical routine to keep my main chisels and planes sharp. It seems to always go way past too dull, I have anxiety about how long it’s now going to take to get it all tuned up again, and then a marathon Sunday just to get to adequate.


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Brad, my sharpening is just part of my day to day workflow. Before every jointing session, I sharpen the plane. I keep a leather strop board on the bench and give the chisel a few strokes from time to time as I work with it. When that doesn’t do it anymore, then, I stop and sharpen it (and while I’m at it, I do a couple more chisels). Using a honing guide on a granite with 6 steps of 3M micron papers is pretty quick. I can usually go over a year before I have to reestablish the primary bevel (when the microbevel gets big enough it’s not micro anymore). I don’t think I want to go down Colin’s rabbit hole although it would be interesting seeing how well my process works. But for me, the proof has to be in the cutting.

Bob, would you be willing to demonstrate at a future zoom meetup?


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Sure. It would only take very few minutes. I think I might actually be available the next one, although if it’s this weekend, I might be out in the river.

As promised, after use pics
All of the pics are about ~800 to 1000 X magnification depending on the size of your screen, say between 14" and 17"
Microbevel-

Back of blade

Some chips in places on microbevel

And also the back

This is a shot directly on the edge of the blade. The flecks you see are dust, not metal.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

For some kind of reference a pic at same magnification (cropped) of the surface of a well worn 1200 grit (15 micron) Eze-Lap diamond stone.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Wow, that’s amazing to see the before and after. Colin, what is your procedure for bringing it back to the initial edge shown in the first post? Does it require more than a leather strop?


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Stropping will round over the edges, which I don't like for this kind of work.
I know Paul Sellers goes to 1200 grit diamond and then strops his edges, but have you seen the radius he ends up with?
To get the edge back, I'd have to raise a burr on the back first, probably need a bit of work on the the 5K for that, then go to the polishing with a Naniwa 10,000.
I use a Veritas Mk 2 guide.
I go for removing the burr each time after the stones, even if I can't feel one on the 10K (just a touch with the blade still in the guide with both stones)
Then on to 1.0 micron/0.3 micron lapping film, remove from the guide and touch up the back with each of the lapping films.
Follow that again with a light stropping bevel and back on untreated leather back and front.

I don't normally use the lapping films, just got them for this testing.

Normally if I need a very keen edge (for jointing plates say) I go up to the 10K (~2.0 microns) and then finish using 0.3 micron chromium oxide on Obeche or Balsa wood (still in the guide, not on a strop) followed by several light strops on untreated leather.

Hope that makes sense.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Very very cool. Thanks for the "after use" photography. I had never seen a magnified diamond stone surface before. I predict there will be cryo steel, et.al., in your future studies.
If I wouldn't have started building guitars, I would probably be forging blades. There is just something mystical, magical even, about both arts.

_________________
Measure Twice,

Karl Borum

One thing that came to mind here is how early solutions we used to get over the hump of inexperience and lack of skill can be hinderances as we progress. Early on, freehand sharpening is a mess. It's more likely to mess up edges as accomplish anything else. Often, we move to jigs and fixtures to speed up the learning curve. Unfortunately, they have their own disadvantages - slow to setup, fiddly to get right, limited in options, etc, but they get us back to sharp a lot faster and more predictably.

Then, as our skills and abilities progress, we are able to get better results without the extra help, and often move past our early "crutches."

For example, as I got better at it, I tested a lot of edges and decided that using jigs for final honing makes edges that are very sharp, but they fail a lot earlier in use.

The trouble for me became work flow progression. Chipped or rolled edges take WAY longer to correct than worn edges. What should have been a half minute refresh took half an hour. That started a snowball effect... It's going to take forever to sort out anyway, so push further into the dulling cycle before resharpening. Lather, rinse, repeat.

So, for example, working out a method and tools to produce en edge that doesn't roll or chip, I can then refresh it a LOT faster, which makes the whole work cycle more favorable. If I don't need to grind damage out, I can just give it a quick touch up and off I go. 1 minute vs thirty minutes.

The thing is, early on, you don't know what you don't know, and even if you did, you may not have the skills to get to where you need to go reliably.

Well, I'm sticking with my jigs at least so far -50 seconds isn't too bad - see from 9:45

https://www.youtube.com/watch?v=7T1p3vfV-vI from 9:45

I also use diamonds initially then waterstones, and things can go pretty slick .

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I am absolutely with Colin, using honing jigs. Exact angles, repeatability...

A bit off topic but I have mutliples of most of my tools so instead of stopping and sharpening mid job I just pick up a new tool. I then have a gigantic sharpening session and do every chisel and plane I can get my hands on. (and scrapers if I am feeling virtuous!). This is quite efficient since you have everything set up.

Dave

So true, and not limited to sharpening! I think it is important to assess one's skills realistically, but without negative feelings about it, and get a good handle on where we each are in our development. If we don't have a specific skill worked out yet, there are things that can help us get the job done anyway, and that's fine. As we develop the skill in question, maybe we move away from what worked before. That's fine, too.

I sometimes do touch ups by hand between jig sharpenings, and can get a fine edge maybe 2/3/4 times in the middle of a job (especially when carving braces), but I always go back the my jigs.
As Dave said, I like repeatability and don't want my angles up or down.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

And I've found out something from my dive into this.
My DMT XXF, supposedly 8000 grit seems to have lost nearly all of of its diamonds. After 10/11 years of use I have been honing on a steel plate. The rogue scratches in the pis seem to have come from the scratches in that plate, NOT from some odd larger diamond particles or contamination as I thought, so I've got a new stone coming to fit into my sharpening sequence.
And I'll put in a good word for the DMT DiaFlat 95 micron to flatten water stones.
Expensive, but it seems to be everything they claim.
Mine is anyway.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Sharpening is a huge rabbit hole. I have pretty much everything. I use my Veritas power sharpener on 90% of my plane blades and chisels ending with cotton from an old dress shirt and green compound on the disc.

Come show us at the meeting next Saturday!

Question for you folks - does anyone spend time making mirror on the back of their chisels? I know it’s useful for making 45 cuts but is there anything more than that?


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The back is one side of the edge. I don’t shine the whole back, but I do make the area near the cutting edge shiny.

I do shine the back. I use a small buffing wheel with compound to get there, so it’s pretty easy.