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Discussion Starter #1
Just got my jointer knives sharpened for the first time & in setting them back up in the cutter head w/ a dial indicator, all three knives are about 3-4 thousandths of an inch less high in the middle. I'm guessing this is from being ground more in those spots, but not sure really why. Feel I should note that when I set them prior to sharpening they were flat across using the same methods, so I don't believe my technique is to blame. I've seen a method of sharpening them with a whet stone laid across the cutter head and the cutter head running. This is mentioned in the manual for my old model 60 jointer. I'm curious if any of you have tried this or any other methods for evening out the height discrepancy in your knives?
 

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I sharpen mine with wet-or-dry sandpaper on a granite surface plate with the Veritas jig. It goes quicker than you might think, and they are dead straight.

I wouldn't send those back to wherever they were ground like that.

I have micrometers and dial indicators for setting different things, but find it quicker, easier, and just as accurate to set them with a small strip of wood by feel using the outfeed table.

I timed it the last time I sharpened and reinstalled them on a 6" and it was about 15 minutes total.
 

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It sounds like when the knives were ground they had them bent in the machine. Freshly ground knives should be perfectly straight. I freehand grind my knives and get them closer than that.
 

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Discussion Starter #4
Yeah I think taking them out & using a jig sounds safer, I'm at work now but ill upload a photo of the process described in the manual, putting a stone on a spinning cutting head just doesn't sound safe, maybe I'm wrong but I'm still new to these machines & want to respect their ability to cause serious injury. I'm just hoping there's a way to salvage these blades, preferably without dropping a lot more cash.
 

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Yeah I think taking them out & using a jig sounds safer, I'm at work now but ill upload a photo of the process described in the manual, putting a stone on a spinning cutting head just doesn't sound safe, maybe I'm wrong but I'm still new to these machines & want to respect their ability to cause serious injury. I'm just hoping there's a way to salvage these blades, preferably without dropping a lot more cash.
No, you don't hone the blades while the machine is running. That would just dull the blades anyway. There are jigs that rest on the rear table that you slide the stone back and forth on one knife at a time. Personally I prefer to hone them off the machine.
 

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Discussion Starter #6
Steve, I thought the same thing. This was the page from the powermatic model 60 manual i was referring to below. I figured unless someone here had tried something like this & had positive feed back, i wasn't going to!
 

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I can't believe they suggested that...do your self a favor and skip that method.
 

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The first statement in your post "Just got my jointer knives sharpened for the first time" reads like you sent the blades out to be sharpened. Then the rest of the post seems to imply that you sharpened them blades yourself. Which is it?

George
 

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In post 6 I wonder how many times you would hone the blades before your rear table was honed down where the jointer was ruined.
 

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Discussion Starter #10
George, I had them sent out to be sharpened. The one multi gauge is the dial I'm using to set them back into the cutter head & I'd actually really recommend this tool big time. Steve, glad I'm not the only one who thought that.. I guess in their defense this manual was written in the 60's??

As an update since doing it 'properly' (what worked really well when they were the same height across the edge) wasn't working for setting them, I tried setting them another way. Instead of setting and securing the two outside bolts & then moving to the three in the middle (which was now lower than the out feed table), I started with setting the low points to the correct height and tightening them up then moving to the outside and forcing the knife down with a block of wood. This actually worked well and now I've got each blade set 1-2 thousandths above the out feed table all the way across, though I'm sure the knife is a little torqued. Just about to make my first test cut, finally! :)
 

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Discussion Starter #11
Looking pretty good! Thanks for your input guys, next time they're in need of sharpening I think I'll go for the veritas jig. I'm just glad after waiting a week I was able get my jointer back up & running without needing to wait for them or a jig to get here. Also George my q's about how to fix it myself were so I could avoid sending em out to come back no better, think I misunderstood what you were saying. Thanks again, I'm learning :)
 

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