Reducing Scalloping and Snipe on the jointer

[Dan Barr]

Just looking for advice on how to reduce scalloping and snipe.

I read the following:

Setting the knives within .002 or .003 of each other, along with good technique will take care of the scalloping.

Adjusting the outfeed table slightly will most likely take care of the snipe on the end.

Please provide any input on these and any other jointer fine tuning advice.

Thanks,

Dan

[Jim Nardi]

Sharper knives and a slow feed rate reduce feed rate will lessen the scalloping.

[Jason Beam]

Here's how i do it:

First, with a true straight edge (lee valley makes a nice 3' steel one at a reasonable price), I check that my outfeed table is flat. There isn't a huge amount you can do if it isn't, so it's more of just an awareness thing. You could grind down high spots, or have it machined, if it's way off - more than a few thousandths, to me, is way off.

Then I check that my outfeed table is coplanar with my infeed table. Both in length and in width. This is one of the tougher adjustments to make, depending on the jointer, but it's worth the trouble if you want straight and square stock to come off it.

One-Way Multi-Gauge (woodcraft sells it)
I rest the multi gauge on my outfeed table and Zero it out.

Then I slide it over the cutter head and adjust every knife to be EXACTLY in line with one another. It might be overkill by some, but when I want precise, I be precise so I go to less than .001" of difference between any knife's height.


I also ensure that they're perfectly parallel with the outfeed table across the entire width of the blade.

Then I adjust the outfeed table to be EXACTLY (less than .001") even with top dead center of the blades. this is also the time where I verify that I got all the knives right.

Now that the jointer's well-tuned, my feed rate has far less impact on scalloping since there really isn't much. I have to run at the jointer pretty quickly if I want scalloping. Also, depth of cut can really amplify any problems with your feed rate, too. Go slow and you'll get smaller scallops, probably undetectable.

As for snipe, by having the knives end exactly level with the outfeed table, I don't get snipe. I apply all my pressure on the outfeed side as soon as possible (once i'm past the cutter head about a foot or so) and that helps quite a lot. Also, I don't push down much because I want to avoid flexing out any cup or bowing that would just cost more wood to remove otherwise.

That's how I get good results. :)

[Gary Keedwell]

I was at the end of my rope when I finally sent away for a real straight edge. Before that I was pulling my hair out every nite for over a week. When I finally put the straight edge on ( I have a 4' Starrett) I saw that my out-feed table was sagging at the very far end from the cutter.. Got my manual out and messed with the gibs and after an hour or so I was jointing nice straight edges.
Both infeed and out feed have to be co-planer. I see that there are now less expensive straight-edges that weren't available a few years ago.
Good luck,
Gary

PS. Even if it isn't a co-planer problem, every serious woodworker should have a "standard" straight edge in the shop.

[glenn bradley]

Others here have given good advice. I'll just re-emphasize that a decent straight edge and a block of time spent tuning will increase your enjoyment in the shop ten-fold.

When I'm getting ready for a tuning session, knife change, alignment session, heck even when I'm getting ready to do a fair amount of sharpening; I just put myself in the state of mind that 'this is gonna take awhile'. I don't try to hurry up and get done. I take it slow and easy and find I actually feel more of a reward when done knowing that I gave it my full attention, the needed time and I'll reap the benefits for a long time to come.