From rust to great scissor

G

G-son

Joined
Apr 26, 2016
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28
Got my hands on this old Rich. A. Herder dressmakers shears made in Solingen, Germany, and spent a little time bringing them back to life.

As bought condition. (25kr roughly equals $2,50 US)





After ~2h bathing in citric acid, reassembled just for testing. Didn't cut fabric, but paper was no problem. Then again, childrens scissors made of plastic cuts paper too...





Comparison, one blade untouched, the other has had the inside slightly flattened to remove pitting due to the rust along the edge. (Notice the shallow hollow grind, the stones only touch the edges of the blade.)



All sharpening complete. The two small stones were used for flattening and "polishing" the inside of the blades (as much as a washita can be said to polish), the coarser large stone was used alone for the "outside" edge.



Job complete. Tried it on denim and a few other things, works well. Another old quality product (pre WW2 I'm guessing) back in useful condition again, lots of life left in it as long as it's kept dry so it doesn't rust again.

 
Good snag! Back when I worked a job overseeing stormwater catch basin cleanings we'd find all sorts of stuff down the storm drains, and at one point I found some old beastly shears that, upon looking them up online, were shingle-cutting shears. The sludge in the bottom of catch basins isn't just nasty--it's corrosive, too, and so the shears were all crusted with rust, but most of the nickel plating remained despite some bad pitting. With a liberal application of elbow grease I was able to get them cutting well again and they're now a "beater" set of shears for outdoor work when I might muck them up.

For the interior of the blades you should avoid using a flat honing surface. The interior faces must remain hollow to ensure proper shearing action. It's possible to still get good cuts from a shear with flattened faces, but you run a much greater risk of any deformation of the edges or resistance from the target material causing the blades to separate and fail to properly cut. Ideally, use a slow-speed water cooled grinding wheel, or else if a manual stone must be used you can use the curved edge of a canoe-shaped scythe stone to mimic the motion of a wheel.
 
Thanks!

I used flat stones for the interior because it needed very little metal removed, making only a narrow flat area near the cutting edge. From what I've understood talking to someone who used to sharpen shears professionally, a very light flattening of the inside is normal practice along with the normal grind on the outside edge. Redoing the hollow grind comes when the flat edges has become too wide, if it does.
I have also two larger shears that had more severe pitting on the inside of the edge when I got them. I used the curved side of a schythe hone, just as you suggested, to preserve the hollow grind while removing the rust damage. I think I spent around an hour just on the inside on each blade doing that - everything else was quick and easy.
 
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