Sharpening a large pair of antique canvas scissors?

J

jtwodogs

Joined
Feb 1, 2009
Messages
421
I have come into possession of a large pair of antique canvas scissors, they look to be in extremely good shape for their age.
I went to the custom search engine and typed in sharpening scissors. I got several explanations and how people have sharpened scissors. Was actually looking for a video, as I seem to learn better seeing it visually. Don't want to ruin them so not going to trust just any you tube video without someone from here verifying it is a good one. Thanks for your help.
 
It looks to me like scissors are a single bevel edge. I would try running it on a whetstone or something like that. Also, if the scissors are not tight when closing they won't cut well. Make sure the pivot pin is not worn out.
 
Really good scissors can be taken apart and sharpened separately. If not, do each side as a separate blade. The set will need to be opened to a full 90% to work each side.

Clean up the top side so it is smooth and flat. Do the bevels as accurately as possible. Work the edge down to a fine grit and carefully remove any wire. It must be absolutely straight and not have any wavy grinding. The angle is very steep compared to a knife. We use the acute included angle to describe an edge, but in scissors, the terminology is compared to a 90° angle. So, 15° for scissors is really what we would think of as a 75° edge.

The angles are almost always different for the cutting edge ( fingers) and the "shear" edge ( thumb). Remember that a pair of scissors is not really two cutting edges that move past each other. Only the top does the cutting. The other edge ( the shear) is what holds the material being cut while the blade cuts it. Usually the shear is only 5-15°. The cutting edge can vary from 5-10° for metal shears to 35-45° for fine cutting scissors used in hair work or dressmaking. Canvas shears should be somewhere in the middle of that.

What you want to end up with is a cutting edge that rides along the shear edge, with the two just touching at the intersection of the two blade. Any nicks or other things that will impede this will make it cut poorly.
 
What Stacy said...

I used to sharpen scissors commercially and just matched the factory bevels. Did it free hand on a 1" belt grinder using a 320 belt.
 
Take it to a pro.I've messed them up using special fixtures.Or practice a lot before you attempt.
 
Stacy explained it pretty well. I also agree with the last post, try sharpening others first or take them to a pro.
What kind of tools or equipment do you have available?
 
I get good results on a disk sander (grinder). As Stacy said, take them apart or open them up, and carefully match the factory bevel- use the old "color the bevel with a felt tip marker" trick if it helps, or just use good glasses. A lot of sharpeners put the inner face flat on a bench stone and pull away from the edge to deburr- that inner edge needs to be as flat and clean and true as you can get it.
 
You must log in or register to reply here.
Back
Top