Setting jointer knives on a Grizzly G0586

[Brian Runau]

I've removed the springs years ago, done this many times, but.... I set the height using the tool and check with a feeler gauge. Knives are moving up as I tightened the bolts. Trying to guess how low to set them before tightening the bolts is a crap shoot. Not had this problem before. Appreciate any advice. Brian

[Bill Howatt]

Any marks on the blades at the bolt contact area such that it is catching rather than slipping? Ends of bolts nice?
Just a guess, but maybe a tiny film of lube at the bolt contact area may help.
How much do you estimate they are usually moving up?

[Randy Heinemann]

I'm not familiar with the Grizzly jointer, but I assume that, if your knives are the traditional steel jointer knives, that the process for setting the should be similar to others.

Before I had a helical head jointer, I used a magnetic knife setting jig which is now sold under Rockler's name (maybe they bought it from the company who originally developed it). I found a similar problem to the one you describe, even with this jig, but out of the box my results were better. I experimented with shimming the jig on one side with Scotch Tape. In my case one layer of tape was enough to keep the jointer knives where I wanted them when tightening the nuts back down. I wish I could remember where I saw that tip (because it's not original with me), but I have no idea. Anyway, the jig is $30 from Rockler and it might be worth trying. I found that it took most of the guesswork out of setting the knives.

One other thing...You indicated you removed the springs. If these springs are part of the knife holder within the butterhead, I'd suggest replacing them. They were there for a reason. Not having them may be contributing to your problems and the results you get. Just a suggestion.

The final solution, of course, is to get a helical head jointer, but I realize that might not be a solution for everyone.

[Randy Heinemann]

Bill's suggestion about marks in the blades and bolts is a good one and could be worth examining if the jointer is older and has had a lot of use.

I do think it's common for the knives to move a tiny bit when being tightened down. I have seen this problem detailed over many years quite often. I know it was a problem that gave me headaches throughout the many years I owned a standard jointer. Even a very tiny amount of shift while tightening can be the difference between the correct setup and one that produces less than desirable results. I think that's why I found the jig now sold by Rockler so valuable. It cut my knife installation time down to nothing, especially when I found out about the Scotch tape shimming of the jig. The biggest problem I had after that was remembering how to reinstall and use the jig each time since I really didn't do it very often.

[Andrew Hughes]

What I’ve found setting knives on my jointer is the knives don’t really rise up when the gibs bolts are tightened.
The pressure from the gibs bolts open up the thin part of the head it’s pushing against. The cutting circle is opening up.
My head opens up about 2 and one half thousand.
I like to go around the head twice to get the knives as close as possible. My jointer has lifters to raise the knives I use a raw head hammer to smack them down.
I actually enjoy the process and use good T1 hss knives perfectly in balance with a straight sharp edge. Very important the knives edges are straight.
Good Luck

[Bill Howatt]

I thought it was scary when I read it but the manual for my old Asian jointer said (I'm going from memory here), after setting the knives, to put a piece of paper on the outfeed table and then put a flat sharpening stone on it and then turn on the jointer and lap the blades with the stone by moving it across the table. You want them just proud of the outfeed table. I did it a couple of times, it makes a hissing sound.

[Warren Lake]

got a magnetic thing with some knives and tried it once and it wasnt even close to accurate. Maybe used wrong no patience for it. Make sure your bolt heads are totally clean and smooth that they are not gripping as you turn them. I dont use springs. I snug enough that I can move stuff just barely and when its right snug a bit more., I probably spin the head two to three times before they are tight. Told that was the correct way. Even loosening the knives go around once at least backing stuff off but not loose. Not loosened off one knife only and removing it. Right or wrong it adds next to no time. Never needed to run a stone on the knives to make them even. 0005 is more than close enough. Stoning will give you a secondary bevel right away.