Question About Setting Knives on DJ20

[Chris Damato]

Hi,

I am in the process of setting the knives on my DJ20. Once I adjust my knives where I want them, and go to tighten the 4 bolts which hold the knives in place, the knives seem to creep up a bit. I have tried this numerous times by keeping the bolts fairly tight while adjusting the knives up as well as applying downward pressure to the lockbar while I tighten the bolts, still with no success. Can anybody please share with me how they tighten everything down on their DJ20 before I pull what little hair I have left out?

Thanks and Happy Holidays!

-Chris

[Joe Grout]

Lay a piece of softwood ( pine/alder about 2" wide on top of the center of the knives. Hold down with one hand, tighten bolts in increments with the other. it should take about three passes to get them tight .

Joe

[Brian Hale]

When i tighten the bolts on my 6" jointer i snug up the 2 outside bolts on each blade and get the height even, then i tighten all the center bolts a little at a time while checking the height. Next I'll do the 2 outside bolts. Finally the remaining bolts get tightened.

Keep in mind that the cutter head is a solid piece of steel with large grooves cut in it for the knives. If you set 1 knife and tighten all the bolts for that knife before moving on to the next, you're actually deforming the cutter head a bit which changes the blade height a bit. Developing a sequence for snugging all the blades first and then going back for a final tightening will give you more consistent results. You can also loosen up one blade a tad to give yourself a .001 - .003 change in height.

Hope that makes sense...... Our Christmas eve tradition is under way.

Cheers!

Brian :)

[Roger Everett]

Chris:
First is to only change and adjust 1 knife at a time, to avoid deforming cutter head. Take out knife and clean the grove and gib throughly. I use a Magna Set Joiner Jig ( magnetic ), and tighten in a torque sequence, such as 2-4-1-3. I generally go thru about 5 passes from just bearly snug to completely tight.
I might add that after setting all the blades, I go thru with a Rollocator(sp.) ( dial indicator) to double check everything is right on and flush with outfeed table.
HTH
Roger

[Mark Singer]

I just use a straight edge of the outfeed table....spin the head by hand and move the straight edge, it should just touch....check both ends. Use the jack screws and you can push down on the knife as you tighten....check them all when your done. if you run a board through and it snipes lower the outfeed table a touch

[Joe Grout]

I just use a straight edge of the outfeed table....spin the head by hand and move the straight edge,

Hope you use aluminum straightedge. :o

I should say that with a DJ20 there are jack screws to hold the knife at the right height . I snug the knife gib just enough to hold the knife and use the same softwood stick to check the knife for the proper height. This is much like Mark Singer described. Then using the flat 2" wide side of the stick held on the outfeed table and on top of the knife I put pressure on the knife and tighten the bolts just a bit at a time. I then recheck the knife to make sure it has not moved after I am done tightening the gib. If it does move I just loosen the bolts reset and retighten.

Joe