Alright what am I doing wrong on the jointer?

Here recently I can’t seem to joint a board to save my life. Never had an issue with it before but now, I don’t know. I’m trying to make an endgrain cutting board and have made two this past Christmas, but now I’m doing something wrong and I guess I need to re-evaluate my technique or something.

I’ll start out with a board like this. Pretty flat already right? No rocking, pretty solid on the table. Shouldn’t need but a couple passes.

Then I get started on it and end up with a board like this where the raised end just gets more and more exaggerated and the whole thing becomes tapered.


I’ve done it on about three boards now and it’s just a waste of wood until I figure this out. What’s the technique for going across the jointer? Where do you apply pressure? I’ve been watching YT jointing technique vids and some people recommend applying no pressure, some on the outfeed table, and some on the infeed table. In woodshop basics it was recommended that we just move the board across the blade and don’t apply any pressure anywhere beyond what’s needed to move it across the blade and that, because the jointer is taking off the perfect amount to inline with the outfeed table, no pressure should be needed. That doesn’t seem to be working for me anymore.

I don’t think it’s something being catawampus with the table either because no one else has been reporting issues with it.

Have you tried rotating the board between cuts?

My best guess would be you are putting enough pressure on the board to bend the board down toward the outfeed table once you pass the cutters.

Look at this pic:

Top image is your board on the infeed table.

Middle image is the board just far enough past the cutter to clip the leading edge.

Bottom image is my poor attempt at simulating what happens when you put pressure on the board in a way that closes down some of the original gap. To be in that position, you have in effect made it seem like the outfeed table is lower than it really is … and it allows the cutter to start cutting into the bottom of the rest of the board too soon.

How I would do it:
Place downward pressure ONLY on the material on the outfeed table over the section you cut on that pass, but DO NOT put pressure on the part that was too high to contact the cutter. On the back end of the board, you are just wanting to apply forward movement and enough down pressure to keep the contact point in contact with the infeed table.

Hope that is clear … but if not ask questions.

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Is that a common way to do it? I thought that would throw off the jointing process since you’re not hitting the face from the same direction every time so could be introducing new variance with each rotation.

Yah I feel like that’s generally how I’d been doing it. I tried putting more pressure on the outfeed table portion yesterday (like really pushing down on it vs just maintaining minor pressure) which is how I got the pictures I just posted.

Looking back at your pic, it may be that your bow is not centered and has a sharper downward bend on the lead end. Appears the largest gap is about 1/4 of the length from the lead edge. In that case, it’s hard to not start cutting into the bottom too soon and that naturally leads to a taper. Try stopping the cut just after the cutting action stops, lift off and repeat until you begin to get a more uniform gap across the length. In a severe case, you may need to clip both ends this way until you get close at which point you can start running the full length.

A convenient technique is to lay a straight edge flat on the table beside the plank and mark a line at the top of the straight edge. Then manage your cutting to sneak up on the line. Once close, joint normally.

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The direction you push the board through the jointer shouldn’t matter as far as flattening the face of the board. However, depending on the wood and the grain, sometimes you’ll get a slightly smoother cut going one direction than you will with the other. (One direction will cause tear-out.) I usually run a board through both directions to check.

When you’re flattening the face of a board, you’re taking out the high point(s). If a board is cupped or bowed, you want the cup or bow facing down with the hump in the middle up. (Otherwise the board will rock on the infeed table.) When you push it through jointer, you’re taking a little off each end until you get a flat face. So it shouldn’t matter which direction you push the board through the jointer as long (as tear-out isn’t an issue, as noted).

Your classroom instructions are correct. You’re pushing the board forward through the jointer, not pushing it down against the infeed table and into the blade. If you do that, you could wind up flattening the cup or bow out of the board before it reaches the jointer blade, which would defeat the whole purpose. Pushing down on the board on the outfeed table after it has passed the blade shouldn’t cause a problem.

I don’t see this in your pictures, but one common problem I run into flattening a board is that it gets noticeably thinner on one side than the other. A little bit is to be expected, depending on where the problem is in the board. But I found my problem was sometimes being caused by inadvertantly pushing down too hard on the infeed side. Flipping the board around between passes helped me get back on track.

I don’t know if they taught this to you in the class, but the jointer is a unique tool. It is the only tool in the shop that can straighten out a crooked board (absent the use of some special jig). The planer can only make a board thinner. The table saw will make two edges parallel.

Good luck,

Jim

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Not sure I follow what you mean on this part.

That should have said “until you get close to the line”

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I am going to suggest the problem is inconsistent pressure while feeding the boards through the Jointer. For proper outcomes, the board has to have consistent pressure and contact with the table throughout the whole length of the board.

Hold light pressure on the board about 6-8’ inches behind the cutter head to start the cut, advance the board with through the cutter head about 6-8’ and then keep balanced pressure on the board until it is all the way through the cut.

It looks like all of the pressure is on the trailing edge an on the infeed table, creating a deeper cut on the last portion of the board.

Stop mee next time I’m in the shop and we can run through a couple of techniques to see if they help.

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If you are getting snipe on the trailing end of the cut the outfeed table is too low and the board drops deeper into the blades after the end falls off the infeed table.

If getting a tapered cut the outfeed table is too high. You might see the board lifted above the infeed table in front of the cutter.

The adjustment lever on our jointer is pretty hard to get fine adjustments. I used a folded dollar bill a few weeks ago on the limit screw to tweek the height down a bit.

If you place the edge of a 6-12" board on the outfeed table with the end resting on a jointer blade and manually rotate the cutter head, you should only move the board about 1/4 inch.
If it moves too much then the outfeed table is low
If it doesn’t move the outfeed table is high

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If the leading end of the board starts to lift off the outfeed table, easily visible after 1-2’ of cut, the outfeed table is high, don’t bother trying to push it down, it’s too late. You will end up with a convex edge, first half is lifted off outfeed table, and when you push that end down it lifts the trailing end and doesn’t cut.

Snipe is pretty easy to hear, the pitch will change just before the trailing end is finished

Since you’ll flip the board end to end to plane each end separately, marking the line on BOTH long sides of the board is helpful.

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f you place the edge of a 6-12" board on the outfeed table with the end resting on a jointer blade and manually rotate the cutter head, you should only move the board about 1/4 inch

Move the board up and down a quarter of an inch? Not sure I follow.

I don’t really know how but I’m going to check the out feed table when I’m back at the space. I was even having the issue with edge jointing last night and you barely have to do anything to get that right. I’m stuck with the table being an issue in my mind considering I’ve been jointing no problem up til recently, but I’d imagine other people would be reporting issues as well if that were the case.

Lots of suggestions in this thread:

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This website also has good info. The blade will move the gauge along its length. This picture and website explains it better than i did, and recommends getting only 2-4mm of movement when the table is correct height relative to the blade.
IMG_2803_edited-3

https://www.rpwoodwork.com/blog/2014/08/

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Well
All the conjecture is great, but if you set the jointer properly it will eliminate a lot of the problems

I looked at the table settings tonight and they were parallel but the cutter head was probably 1/16 below the table line.

No way to get a good cut with that set up. And no technique will overcome a poor machine set up

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Seems to have done it. Used it last night and it worked perfectly and feels right once again.

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