Anybody know what this tool is for?

[WhistlingBadger]

A few days ago I received this in the  mail from China.  (yes, I sanitized it)  I checked through my recent purchases on ebay and Amazon and I'm pretty sure I never ordered this thing.  Oh well, the law says it's mine now.  And it looks darned useful.  So next challenge:  Figure out what the heck it is.  The pink thing inside is a coarse, concave grindstone that can move up and down when the outside handle is depressed.  The description on the package just said "Chain grinding."

IMG_20200416_093113 by Thomas Wilson, on Flickr

IMG_20200416_093145 by Thomas Wilson, on Flickr

IMG_20200416_093205 by Thomas Wilson, on Flickr

Any ideas, oh PA Oracle?

T

[Handforged]

It is used on the end of a chainsaw bar to sharpen the chain. You clamp the plastic part around the bar, start the saw at a low speed and push the little black foot into the ground. That pushes the stone against the chain while it spins sharpening it.  The end of the bar has to be slotted to use this contraption.

Footnote: They suck something fierce. They will sharpen a chain a few times but it only sharpens the top of the tooth, not the notch that does most of the cutting.

[WhistlingBadger]

Ooooookay, that makes sense.  Thanks, HF.  Yeah, I can't see any possible way that could be very effective.  Dang, thought maybe I scored something useful.  I guess I can bust the rock out of it and use it as a coarse hone for my garden tools...