Got one because I had to have it, second because it was a deal(and I was able to make a trade for it, which made it a better deal), and the third one because it was the one I wanted in the first place but was too cheap to pay much for it(got a great price on that too
).
I have a few round grinders, and a raker grinder too
.
I sharpen on the saw most times when they need touched up for round chain, use the round grinders when they get rocked, and the square most times as the files are stupid expensive these days. I do save my retired double-bevel files for doing rakers as they cut very nicely, and you gotta get your money's worth out of them. The raker grinder gets used anytime I use the grinders on a chain as I equalize the length of the cutters so all the rakers can be set at the same height, when I file chains I use a progressive raker guide and set them by hand, probably the only thing progressive you'll catch me doing
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