Before you get in a big hysterical panic about how dangerous this is – or more correctly how dangerous you THINK it is – I should tell you that I got this idea from Fine Woodworking magazine published in the 1980’s. Go scream at them 🙂
Seriously, it’s spinning at around the same speed as it would be on a bench grinder and still has a guard (under the saw) much like that does. It’s a little more open on top but this isn’t and would not be for heavy duty grinding. It’s for sharpening which is light grinding. An insert for the table saw that fits neatly around the wheel is a good idea.
That said, if you do decide to do this, it’s YOUR responsibility. If something goes wrong, you are to blame – no one forced you to do it and if you think it’s not safe don’t do it.
Anyway, it works great. I was able to sharpen 5 sets of knives for my jointer and planer and that’s a total replacement cost of over $300. The planer knives are the disposable types that aren’t made to be sharpened, but I’ve found that you can sharpen these at least once and more, depending on how much you need to grind off to restore the edge.
Taking it to the next level on the stone and then stropping is optional, but doesn’t take long and seems to be worth it. At a minimum you need to get rid of the wired edge that grinding produces.

▶️ Project plans for sale: https://ibuildit.ca/plans/
▶️Support the work I do on Locals:
https://ibuildit.locals.com/
▶️ Patreon:
https://www.patreon.com/user?u=865843&ty=h
▶️ Join my Makers Mob for detailed build tutorials:
https://go.themakersmob.com/john-heisz-i-build-it/?via=ibuildit

My “Scrap bin” channel:
https://www.youtube.com/c/IBuildItScrapBin

#ibuildit
#woodworking

Website: https://ibuildit.ca/
Facebook: https://www.facebook.com/I-Build-It-258048014240900/
Instagram: https://www.instagram.com/i_build_it.ca/