Thursday, May 14, 2015

Shoe Making: Leather Skiving with Curved Blade

My go-to knife for skiving is this Swiss stainless steel curved blade that I converted from a Kitchen knife.
Sometimes however, you must use a straight knife and the only straight edge knife for me is the Carreducker that I got in 2011. The Carreducker is at about 15 degrees angle, I do not like those knifes at 60 degrees; they are too heavy, too thick, and clumsy.

On my curved edge knife the steel is tapered from handle to point to about half thickness.

They are of course only sharpened on one side and flat on the other.

I use 1/2" 2 sided tape for all my hemming and so I skive the full 1/2"

This 3M tape has ultra thin adhesive so two or more layers don't cause a problem with the sewing machine. Two sided tapes are vastly different, there can be some with very thick adhesive; avoid those. You can use 1/4" tape too.

SKIVING:
My approach to skiving is to get there in three passes:
  1. Take the edge down about 2/3rds thickness and 1/8" in. 
  2. This leaves a ridge to remove so I take that from 1/2 way into the 1/8" skive all the way to the 1/2" line. (I usually scribe the 1/2" line)
  3. Lastly I take the edge down to a fine edge. 
See YT Video

Feeling and looking at the edge is important to know that you have got it down to a nice smooth taper.

SHARPENING:
Here I use the Carreducker method: a piece of sand paper attached to a plank on one side and a piece of leather on the other. I like to use a high quality 220 paper, if you are only touching up the edge one piece of paper may last years. If you are starting a new blade use 120 grit.
Some people are convinced that you need polishing compound on the strop side... I say no, I never use any. My secret is to us an oil tanned leather for the strop. I have a nice piece of Latigo Side Burgundy it has served me well for years.
What's the point of the strop? The strop is to remove the little burr on the edge of the steel. This little burr referred to as the "wire edge" it will always be there, it easily gets broken off by the repeated stropping back and forth. The burr can be felt with your finger tips. I use the "sticks in your finger nail" method of confirming my success.
Remember also you can look right down at the edge of the knife, if you see any light reflected then you know you have a little more work to do.
See YT Video

6 comments:

  1. Found this fabulous blog (and therefore your book blog) by searching for Elna Lotus machines.Your shoes are a work of art. Wrote a LONG comment on Hawkeye/Judith and found I COULD NOT POST IT!!!
    The old books are the best, and Scott is a huge favorite in this house, as is Tennyson. But we all abhor the Leatherstocking series because of Hawkeye's self-righteous judgement of WONDERFUL Judith! Her so-called "failings" get a brief paragraph, and she proves herself OVER AND OVER to be the most worthy of women. Hawkeye's name should be Hubris. I actually threw the last book across the room when I read the ending. After slogging through all those tomes, to have it end like that was reprehensible!

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    1. Thanks I so agree about how annoying Hawkeye can be, he could have given Judith a break!
      I have Pathfinder on deck for the summer. I do like Cooper's wilderness tales during the summer by the lake.
      Sorry about the posting block, I'll switch it off, thanks so much for the comments.

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  2. Hi! I am learning so much from your blog. I want to teach myself to make shoes and am slowly gathering the tools I need for my first project. I have wondered about modifying second hand, good quality knives but yours is the first example I've come across. How did you select the knife and how did you change the shape? Do you think a straight razor could be adapted for skiving?

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    1. Sorry for the late response.
      A straight razor is probably not a good option, it is very thin so would not be good for heavy leather and one of the ways in which you keep from cutting thru to the other side during skiving is to adjust the blade angle close to flat, the razor won't allow that.
      Good luck and keep sharpening!

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  3. "My God! It's full of good info!" (paraphrasing 2001 Space Odyssey) Thanks! Good stuff.

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  4. All your hard work is much appreciated. Nobody can stop to admire you. Lots of appreciation. Formal Shoes for Men

    ReplyDelete