Friday, July 6, 2007

REPAIRING A WRECKED SHEAR ON THE HIRA-TO

















One of my former students sent me a shear that he took in trade for a new shear sale. He told me he was selling shears by the dozens because a sharpener in the area was not sharpening beauty shear properly. He gave all the stylists $25 dollars off his regular discounted price on his shears to replace all the damaged ones.

What I told him I'd do is show how the Hira-To can reconvex a blade that is even severely damaged. So here we go...

You will see the damage in the top picture. (Click on each picture for a better view!) This shear has been bevel-edged and the throat is dipped out.

In the second picture, you can see that I've started the repair on an 80 micron dics. The first thing I had to do was knock the top of the angle on the shear back. I could start by rounding the shear right to the edge because that would have left a hump just above the cutting edge.

In the third picture you'll see that to knock the back of the bevel down, I simply worked the area directly over the back of the angle first before completely convexing the shear to the edge. You can still see some of the left over bevel and the dip in the throat.

In the fourth picture, you can see that I've reached the majority of my edge, but there is still a dip in the throat. To deal with the dip I had to rock back into the throat area and then work the edge radius back into shape. (If you don't understand this, or any of the steps above, call me at Wolff and I'll explain)

The fifth picture shows the blade after I completed the work on the 80 micron disc. You can see that it is loaded with scratches at this point and it had quite a large burr.

The sixth picture shows me working the blade on a 60 micron disc. This will start to remove the scratches created by the 80 micron disc.

The seventh picture down shows the blade after I completed the work on the 60 micron disc. You can see the scratches are finer, but I still have a good bit of work to do.

The eighth picture shows me working the point off the tip. With this much repair, often the tip will bee too pointy.

The ninth picture shows the tip after I re-rounded it.

Picture ten shows me working the blade on the 6000 grit water stone to remove the heavy burrs I created with the 80 and 60 micron discs.

Once I pulled the burr back and reworked the inside line with the water stone, I then worked the blade on the 30, 15 and 9 micron discs. You can see this in picture number eleven.

Picture twelve shows the blade after working it on the 15 micron disc and picture thirteen shows the blade looks after the 9 micron disc.

Picture thirteen shows that after I've worked my blade on all three of these discs, I then go back to the water stone to work the inside.

Once the burrs are pulled back and the shear has a new inside line, I'm ready to start polishing as you can see in picture fourteen.

Picture fifteen shows the completed blade. It is fully polished and reconvexed. This takes a little time to do, but a repair like this will dazzle a customer! If you have any questions about any of these procedures, give me a call at Wolff at 1-800-888-3832. Also. drop some comments below and let me know what you think of this post.

6 comments:

  1. Regarding a deep nick that cuts into the ride line on the back of the cutting edge - what is the proper procedure to remove this ick on the Hira-To and what grit paper should be used?

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  2. The best thing to do is sharpen past the nick! You would do this by starting with an 80 or 60 micron disc to take metal off, working the inside, then going through the rest of the steps from the 30 micron through the polishing step. I'll post an example of this in the future with some tips about how to do this so you don't have a big step down in the throat of the blade.

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  3. Great post Jim! Were you able to get a satisfactory ride line on those?

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  4. Mike

    The ride line I got was just so-so. I will be doing an article in On The Edge that shows how to rework the inside of the shear to bring the back side of the ride area back inline with ride line.

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  5. Jim,
    Here I am trying to sell out and all this good stuff comes along. The help you are giving others will earn you a seat at the table. The food however may not be as good as the information you are passing around for us to digest. Great article.
    RON

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  6. This is very informative post having a lot of useful instrcutional information about sharpening. Truly loved it. Keep us the good work. You can send us update emails at: hunyn@hotmail.com

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