12-02-2017, 01:51 PM
Mr Ken, these are very pertinent scissor questions!
"Should each edge be sharpened the same way?"
It certainly is easier. The important thing is to maintain the original performance for which they were designed, or sharpen them to suit your need.
I'm not sure larger Diameter wheels are inherently better. You can get the same edge angle with practically any size wheel, but the edge bevel would be wider with a large wheel at the same edge angle.
Should the edge which supports the material being cut have a toothy edge to help prevent the cut material from slipping?
If you have one smooth blade, hard material can slip away from it regardless of the other blade's status. I have used a coarse wheel on both blades, instead of having one serrated blade, which seems to work for me.
If you need super traction, they make scissor files to cut serrations into blades. I have no experience with a serration file, but I wouldn't mind giving it a shot.
I have read that there is an advantage in using two grinding wheels when sharpening scissors. I have also read that often only the coarser wheel or belt is used.
This sounds like a TAS statement to me, since you have two wheels at your disposal. If you use the grinding wheel alone, your tool will cut difficult material, like thick plastic or "tin" (as in "tin-snips") better. Actually, they don't really "cut" better, they bite better. No free lunches though. Coarse edges usually don't cut fine material like paper very well, but it's very easy to refine an edge on the "polishing" wheel of a TAS.
A big advantage of a Tormek over a TAS is heat buildup. Tormeks have no heat related issues. Ever. You definitely have to be more careful with a TAS. That follows Mr Rupert's thoughts of SFPM on the wheel.
A very good way to combat heat buildup with a TAS is to start near the tip of the scissor, which takes a bit of practice. Then you're pushing the heat toward the larger mass of the blade which can easily absorb a lot of heat. If you go from the pivot to the tip, the heat can easily build up to the point where the tip will turn blue before the wheel gets close to the tip.
Another advantage for the Tormek is the wide wheel, which makes it much easier to keep an edge straight and true.
The profile of the edge, be it flat, hollow or convex means little compared to it's Angle.
Just my 2¢
"Should each edge be sharpened the same way?"
It certainly is easier. The important thing is to maintain the original performance for which they were designed, or sharpen them to suit your need.
I'm not sure larger Diameter wheels are inherently better. You can get the same edge angle with practically any size wheel, but the edge bevel would be wider with a large wheel at the same edge angle.
Should the edge which supports the material being cut have a toothy edge to help prevent the cut material from slipping?
If you have one smooth blade, hard material can slip away from it regardless of the other blade's status. I have used a coarse wheel on both blades, instead of having one serrated blade, which seems to work for me.
If you need super traction, they make scissor files to cut serrations into blades. I have no experience with a serration file, but I wouldn't mind giving it a shot.
I have read that there is an advantage in using two grinding wheels when sharpening scissors. I have also read that often only the coarser wheel or belt is used.
This sounds like a TAS statement to me, since you have two wheels at your disposal. If you use the grinding wheel alone, your tool will cut difficult material, like thick plastic or "tin" (as in "tin-snips") better. Actually, they don't really "cut" better, they bite better. No free lunches though. Coarse edges usually don't cut fine material like paper very well, but it's very easy to refine an edge on the "polishing" wheel of a TAS.
A big advantage of a Tormek over a TAS is heat buildup. Tormeks have no heat related issues. Ever. You definitely have to be more careful with a TAS. That follows Mr Rupert's thoughts of SFPM on the wheel.
A very good way to combat heat buildup with a TAS is to start near the tip of the scissor, which takes a bit of practice. Then you're pushing the heat toward the larger mass of the blade which can easily absorb a lot of heat. If you go from the pivot to the tip, the heat can easily build up to the point where the tip will turn blue before the wheel gets close to the tip.
Another advantage for the Tormek is the wide wheel, which makes it much easier to keep an edge straight and true.
The profile of the edge, be it flat, hollow or convex means little compared to it's Angle.
Just my 2¢