Jointer Madness Atlanta

[Doug Donnell]

I am at my wits end (although I have been told that is a short trip). I bought an 8" Grizzly jointer a while back, got it assembled, and did all the straight edge work and adjustments, and I THINK I have it dialed in, at least close.

The only problem is when edge jointing, I create rocking chair rockers...

Reading all the articles, posts, and blog videos, I cannot tell what I have done wrong in set up. It may be my technique, but, again, reading all the articles, posts, and blog videos, I cannot tell what I am doing wrong. I start with pressure on the infeed table, and shift to the outfeed table when I have enough board past the cutters.

So basically I can't get the board straight.

I know it is probably something simple and silly, either in the machine setup or my technique. Until someone who actually knows what they are doing watches me or looks at the machine, I despair of getting any use out of this machine. I would be willing to pay a Creeker in the North East Atlanta area, northern Gwinnett County, to come over to my home shop and take a look at the machine and my technique. It would be well invested money on my part.

Anyone able to help? It would be much appreciated.

Doug

[Chris Fournier]

Sounds like you understand the technique involved to get a straight edge from your jointer so lets have a look at your machine.

I would bet that your knives are below or at best level with your outfeed table. I would recommend that you adjust your outfeed table to be .002" to .005" below the height of your knives. This should eliminate your problems.

Disconnect your jointer from the power supply.

An easy way to do this is to take a straight edge of some kind, wood (12"l x 2"w x 3/4"t), aluminum straight edge or metal straight edge (careful). Now make a mark on the straight edge on one side and place the straight edge on its edge with this mark lined up with the leading edge of the outfeed table. Carefully rotate your cutterhead by hand and as the knives turn past TDC they will pull the straight edge forward. You can tell how much by looking at the mark on the straight edge.

Adjust the outfeed table height so that the straight edge is dragged about 1/8" to 3/16".

Use this drag method at both sides of the outfeed table and make sure that the distance travelled by the straight edge is the same. This will tell you if your knives are parallel to the outfeed table.

Remove the straight edge from your jointer table and power up your machine.

If the travel is the same, try jointing again. If it's close, try jointing again. If it's not close at all you'll have to reset your knives and that's for another post.

Try the above and get back to us.

Everyone has been where you are when they got their first jointer and tried to use it so breath deep, relax and don't fret; success is right around the corner.

[Don Jarvie]

1st up, bring the infeed and outfeed tables up so with a straight edge or level everything is straight across. The knives should just touch the bottom of the edge but still spin. Check for any gaps along the two tables. The straight edge should slide across the tables and no gaps should show. If you see any gaps then the tables would need to be adjusted to close the gap. Now you can back down the infeed table to the 1st mark.

Get some scrap that has come off the TS that you know is straight and square, maybe 18 inches long. Run it across the jointer and take off the smallest amount on the indicator. Hold it flat on the infeed table and against the fence. Push it across the table and put a bit of pressure on the outfeed table. I know this sounds elementary but maybe you are trying to take off more (>1/16th) and you might be putting too much pressure on the outfeed side and the wood is coming a hair off the infeed. By taking a 1/32nd the tables are very close to each other so the wood won't rock much.

If you not getting a flat edge then your tables could be off and need adjustment. Even though the jointer is new it might need a few adjustments to get to right.
Good luck

[Steve Mellott]

Doug:

About 2 months ago, I changed the knives on my 8" Grizzly jointer and had the same problem. I thought I had really been careful when I installed the new blades, but they must have been too high or too low. I re-installed the blades and the problem went away. Good luck!

Steve

[Stephen Cherry]

I would not dream of installing jointer blades, or setting height without my trusty Wixey digital height gauge. I set the knives at .000 or -.001. This is a critical adjustment, particularly if you want a strait board. Plan b would be to set the infeed at 1/16 or so below the knives, then watch the board arc change while bringing up the outfeed table from below or above the cutter. A little bit of movement goes a long way.

[fRED mCnEILL]

I was having a dickens of a time getting mine to work properly after a knife change. On my jointer, if the outfeed table and the knives are not EXACTLY at the same heighth I have a problem. And ALL 3 knives have to be adjusted correctly. One knife out of adjustment(which I think was my problem) will create a problem.

[Doug Donnell]

Thanks folks. I thought that I had tried the "drag the straightedge" test, but now I can not remember if I did it for all blades. I am under no illusions that the factory settings are always perfect, I will need to check that. I also think I set the outfeed table to be very close to knife height, as only the barest movement of the straight edge was apparent when I finished. Is it considered better set up to have the knives a bit higher than the outfeed? Seems counter intuitive, but I am willing to try.

I bridged my 36" straightedge over both outfeed and infeed tables with the tables at the same height and the cutterhead rotated between blades. Across the length, I was unable to get a 0.003 feeler gauge under the straightedge anywere, across the full width of the tables and the full length of the straightedge. I could get a 0.001 feeler under a few spots and I believe I got a 0.002 under one spot, but I thought that was a small dip in the infeed table and was not at the cutterhead mouth. That 0.002 dip was not across the full width and with the fence as far back as possible I don't think it was an issue for edge jointing.

As with all things, I have entirely capable of thinking I did something correctly when in fact I haven't. One can learn a great deal from reading, but sometimes you just don't get the technique correct. Does Highland Woodworking or Woodcraft ever have Jointer set up and use classes?

[fRED mCnEILL]

I made a jig to mount my dial indicator so I can make sure the blades are aBSOLUTELY level with the outfeed table and ALL the blades must be bang on. It the blades are higher OR lower than the outfeed table you won't get straight cuts.

[Chris Fournier]

Fred's experience is different from mine. I've found that I get best results with the knives being a tad higher than the outfeed table surface. Under, you get the banana boat, spot on can work but your technique has to be good and you have to be diligent, a spot high and jointing an edge is easy as pie - you will get varying amounts of snipe depending on how high the knives are.

[Van Huskey]

One other thing, don't work on your technique with long boards until you get your techniques down on shorter stuff. I suggest something in the 3ft range you can measure the board after each pass with a caliper to see your progress (or not) on a pass by pass basis.

[Russell Smallwood]

Hey Doug,

I have an old Delta 6" deluxe that uses jack screws for setting the knife height. The barely adequate 3/4 hp + having a Tormek at the ready means I sharpen my jointer knives quite regularly. I used to use the straight-edge method to set the knife height with a good degree of success, but it always seemed to be harder than it should be to get everything just right, and occasionally, I'd get everything set only to find out that something went wrong and I'm getting bad results. Rinse->repeat ad nauseum.

Recently I've started setting the knives using a magnetic jig. While they are intended for use with spring-based blade slots (as opposed to jack screws), I find the jig makes setting the knives a no-brainer and takes 10% of the time it used to with the old method. Basically, I set the knives, lock them down, then go back and adjust the jack screws until they are snug against the bottom of the blades. Works great, no guessing.

[Steve Orbine]

I was told this technique long ago and it has worked well for me. First, of course, make sure tables are flat and parallel.*

Get a board maybe 2 feet long with a good edge. Joint the edge if you need to. Set the jointer for about 1/32". Now, joint only the first 4 inches or so, then lift the board off the jointer. With a pencil, mark up the jointed 4 inch section. Flip the board front to back, so the 4-inch section is now on the trailing edge. Joint the entire edge. When properly set, the pencil marks will be just partially removed. Adjust outfeed table until satisfactory outcome.

*Special comment for older PM60 owners (older PM60, not older owner): My green PM60 came mounted on a heavy steel base. The base was so sturdy that it imparted a twist to the cast iron jointer body when tightly bolted to the base. I spent hours figuring this out, but adding a spacer to relieve the stress straightened everything out nice nice. Your PM60 was ground as a unit during manufacture, so it should be perfect. If you older PM60 is not, check this out.

[Curt Harms]

The procedure outlined by Chris Fournier above is the one that Jet recommends for setting Jointer/Planer knives. Each knife should drag a stick or piece of metal the same distance, about 1/8" and you want to check each end of each knife. I suspect the distance the stick moves is less critical than each end of each knife moving the stick the same distance. Once they're all set the same, you can experiment with the outfeed table height if need be.