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I believe based on some experiments that sharpening your skew on a stone instead of (or in addition to) grinding it will yield improved tool control. I don't have a sufficiently large sample size to support this yet but the bit of anecdotal evidence I've gathered seems moderately compelling. I would be interested if anyone else either already knew this, or can give it a try if you've found the skew tricky to see if it helps at all.
To start with I basically never grind my skew, but instead use those little trend diamond paddles for day-day sharpening so hadn't really put this together in my head before.
I was messing around with it last week and decided to regrind the edge a little bit differently (same sharpening angle but just changing the "skewed" direction a smidge)... Well boy howdy it was suddenly spiral catch city! Especially when trying to turn beads, planing was ok but rolling any curves was not happy.
Took it back over to the diamond paddles and sharpened it a bit more with them which reduced the hollow grind a little and it settled right back down nicely. This was with the same basic included angle on the sharp bits and not changing the shape of the rest of it (or the height of the tool rest .. which can also make a very large difference).
My hypothesis is that a hollow ground bevel doesn't provide enough support behind the cutting edge and sharpening it on a flat stone/diamond gives just a wee bit of extra support behind the edge which helps keep the edge from rotating to quickly into the stock. You can also get the skew sharper by honing than you can with ~most~ grinders which I believe also helps, I do notice that if I've been skewing around a while the probability of a backwards spiral catch goes up and then back down once I sharpen things up again.
So if you're still fighting backward spiral catches with the skew try honing the edge on a bench stone or diamond paddle or.. whatever you use for flat blade sharpening. It doesn't take a lot, less than half a millimeter of flat behind the edge seemed to make a pretty measurable difference.
I also repeated the experiment once just to see and it seemed to have the same behavior (grind - whee many catches, then sharpen on the diamond paddles and great joy).
The effect is very likely larger or smaller depending on how steep of an angle you grind your skew at. I like mine pretty poky so I suspect that may increase the effect somewhat.
To start with I basically never grind my skew, but instead use those little trend diamond paddles for day-day sharpening so hadn't really put this together in my head before.
I was messing around with it last week and decided to regrind the edge a little bit differently (same sharpening angle but just changing the "skewed" direction a smidge)... Well boy howdy it was suddenly spiral catch city! Especially when trying to turn beads, planing was ok but rolling any curves was not happy.
Took it back over to the diamond paddles and sharpened it a bit more with them which reduced the hollow grind a little and it settled right back down nicely. This was with the same basic included angle on the sharp bits and not changing the shape of the rest of it (or the height of the tool rest .. which can also make a very large difference).
My hypothesis is that a hollow ground bevel doesn't provide enough support behind the cutting edge and sharpening it on a flat stone/diamond gives just a wee bit of extra support behind the edge which helps keep the edge from rotating to quickly into the stock. You can also get the skew sharper by honing than you can with ~most~ grinders which I believe also helps, I do notice that if I've been skewing around a while the probability of a backwards spiral catch goes up and then back down once I sharpen things up again.
So if you're still fighting backward spiral catches with the skew try honing the edge on a bench stone or diamond paddle or.. whatever you use for flat blade sharpening. It doesn't take a lot, less than half a millimeter of flat behind the edge seemed to make a pretty measurable difference.
I also repeated the experiment once just to see and it seemed to have the same behavior (grind - whee many catches, then sharpen on the diamond paddles and great joy).
The effect is very likely larger or smaller depending on how steep of an angle you grind your skew at. I like mine pretty poky so I suspect that may increase the effect somewhat.