Sunday, April 6, 2008

Leather Strop

You don't need a grinder and felt wheel in order to keep your knives, gouges, and chisels sharp. Honing with a leather strop charged with a fine compound also keeps them razor sharp. Glue a piece of leather to a flat substrate, like mdf or plywood, and rub a fine grit compound over the surface of the leather. I glued my leather rough side up, but others glue theirs smooth side up.

Slide your knife away from you, with the cutting edge facing you, and keep the blade at the same angle as the bevel. Flip the blade over and pull it towards you, this time with the cutting edge facing away from you. This way you won't gouge the leather. Hone each side of the blade the same number of times.

The lettercarving chisels that I've used for about 12 years have never once touched a waterstone or grinder. I have only ever honed them on a strop and they cut just as well now as the day I bought them. To sharpen a straight chisel, maintain the bevel angle as you slide the chisel towards you, with the cutting edge facing away from you. To hone the back, make sure the chisel is perfectly flat and then follow the same procedure. Always hone each side of the blade the same number of times.

To hone a straight gouge, I use a Flexcut SlipStrop, which has pre-formed shapes that match many types of gouges. Charge this with compound and hone the inside of the blade in the same manner as above. Hone the back of a straight gouge, if the sweep is not too extreme, on the flat leather strop, and rock the blade to match the back of the bevel. I lean the blade to the left and slide it, then lean it in the middle and slide it, and then lean it to the right and slide it. All the same number of times as I hone the inside sweep.

For smaller gouges, I sometimes use a piece of leather that I just bend by hand into a curve that matches the inside curve of the gouge.


Unknown said...

What kind of leather do you use? Thanks for posting!

Adam Aronson said...

VC, silly question from a Stroppin' Noobie... How fast do you push the edge across the leather?

Perfect timing on your post... I just purchased my first strop 'cause I never was satisfied with the edge that the 6000 grit stone was giving me was the best I could achieve.

Also, how about using the strop with the blade from my planes? Any thoughts?

Unknown said...

Hi VC,

This series on alternative honing methods is great! I love using strops, and often use mine smooth side bare, and the suede sides charged with either Green Rouge or Simichrome polish.

I also really enjoyed your articles on letter carving. They are inspirational! I was wondering if you would mind doing a few more articles on lettercarving, showcasing the uses of your various lettercarving chisels. Seeing when and how to apply each would be helpful for even something as simple as deciding which ones to get started with.



Kari Hultman said...

Alexander—you can make a strop from a belt, but the leather I used is cow hide. Make sure when you glue it to the substrate that you roll it flat. You can lay another piece of mdf on top of the unglued side and clamp it, so it flattens out perfectly as the glue dries.

Adam—I have seen guys zip along pretty quickly when honing, but I take it slower to make sure I maintain the same bevel angle.

You can always try honing your plane blades, but I do not. I can't explain it, but for some reason, I get a better edge coming off the 8,000 grit stone. But give it a try. The only thing I would suggest is to use a wide enough piece of leather so you can hone the entire width of the blade at one time rather than in sections.

Rob—Sure, I'll be happy to do more posts on lettercarving. : )

Unknown said...

Where do you learn all this stuff?
Your knowledge is amazing.

Kari Hultman said...

Wyld, I read about woodworking all the time and I have taken classes with some wonderful instructors over the years.

Javier Portero said...

Hi Kari, greetings form Argentina. How often do you change the leather for a new one? Javier.

Kari Hultman said...

Hi Javier in Argentina! I have never changed the leather on my strop and have used it for about 10 years.

Unknown said...

Thanks VC! I was wondering about the method to apply the lapping strokes on a strop. I just made my first strop with two large painter's stir sticks glued together with some heavy leather rough side out on each side. I'm waiting on my polishing compound to arrive and found your blog which answered my question. Thanks again. bob

naomi said...

Kari--your blog is pimptastic--i always come back and search for stuff. I finally took the plunge and got a piece of leather for a strop at Woodcraft after thinking about it since you posted here. I guess i have a few questions:
1. Like you say-everyone uses the smooth side, and you use the rough side--why? What are the pros and cons?
2. a) Whilst at Woodcraft i asked the dude for help with stropping compound. The leather they sell says that technically you don't need compound--what's the deal with that?
b)he gave me this powdery chalky stuff--which was about half the price of the green stuff--is there much difference?
3.Substrate--i notice that the leather doesn't seem to slip so i was thinking about not mounting it (i have also been holding off till i got your opinion about rough or smooth) at all. Would you recommend MDF or plywood? The concern about the MDF is sealing the edges, i suppose...

Kari Hultman said...

Hey Naomi--great questions! I'm going to do a post on this if you don't mind. I'm sure that others will have different opinions, which is great. That way you can choose which ideas work best for you.

naomi said...

Mind? I'm delighted!Looking forward! Cheers!

Kari Hultman said...


Rather than keep you waiting, I decided to answer your questions as best I can. :-) I do not have all the answers, am no expert, and there are a variety of opinions on this subject, so you might also want to check Fine Woodworking and other reputable places on the web for other opinions.

I use a white compound (probably like the chalky stuff you have) only because the man who taught me how to do lettercarving used it.
I think the white stuff is not as fine as the green stuff, but I get a mirror polish just the same.

I have not found a pro or con for using smooth/rough side up. In my opinion, they are probably both exactly the same. If you look at strops sold retail, they are usually rough side up, but I don't think it matters. Once you've used your strop long enough, the fibers lay down and become smooth anyhow.

I have heard people say that it's the compound, not the leather, that hones the blade. However, if you see old movies with barbers, they use a strop hanging from their belt to sharpen the razor, and they do not use compound. I have thought about doing an experiment by putting compound on a piece of mdf and see what happens. I believe this should work, since some people sharpen their gouges by carving a groove with the gouge in a piece of wood and lining the groove with diamond paste.

I would glue the leather to MDF as that is more stable than plywood and is less likely to cup. You do not need to seal the edges of the mdf or plywood. You should definitely glue your leather to a substrate because it must be dead flat in order to sharpen correctly. You do not want your edge to round over. When you sharpen, it's important to keep your wrist stiff and pull the blade toward you at exactly the same angle with each pass.

I hope this helps!!!

Rob said...

Gary Rogowski, a well known Portland, OR woodworker says to glue the split cowhide rough-side up and use Herb's Yellowstone honing compound (available at Woodcraft.) If you go to and search for his name there is a sharpening video where he demonstrates fantastic results following the honing.

On the other hand, David Finck, author of an amazing book, "Making Wooden Planes," and a fine woodworker in his own right, says in his book to glue it down with the smooth side up. He doesn't discuss honing compounds that I recall.

There was an article in Fine Woodworking about ten years ago comparing sharpening methods for chisels and plane irons and the winning method used a very mild abrasive suspension sold by 3M Company put sparingly on the leather.

So I'm going to try both ways: rough side up and rough side down.

Does anyone know if hide glue would be a good adhesive to glue the leather to a piece of baltic birch plywood?