# (NEWBIE) Belly resulting from jointer use



## AESamaan (5 mo ago)

Hello (NEWBIE QUESTION)

I have a new Wen 8" straight blade jointer. I know it isnt professional, but the little use I have gotten out of it has been great.

However, today I noticed that my board had a belly (lifted off straight on both ends). I passed it through the jointer, and it got worse. I changed the cutting height several times, and it got way worse.

What causes a jointer to create a belly on a board, where at least one of the sides is being cut away from straight.


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## Loren (May 30, 2008)

The jointer must be operated skillfully. Assuming it's set up properly a jointer will only straighten or flatten relatively straight or flat stock in one pass. If your wood is bowed or twisted or has a bellied or concave edge remove portions with partial passes on the jointer to get the stock relatively straight or flat. In the case of the belly you want to start perhaps where your marks are and joint off just that section a couple of times. It's easier to remove a concave edge than a belly but if you work judiciously you'll find you can do it without too much trouble. Good luck.


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## rwe2156 (May 7, 2014)

Be sure the outfeed is flush with the cutter knives.

Most of the pressure should be on the outfeed. If you push down too hard on the infeed you'll get what happened to you.


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## SMP (Aug 29, 2018)

2 main things:
Proper setup
Proper use

Did you follow setup instructions? If you are 100% sure it is setup correctly, then it is probably use. Once it has the belly its difficult to get out without some practice.


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## gdaveg (Aug 1, 2020)

To get straight cuts on a jointer put the weight on outfield table as much as possible. If weight is put on he infeed side it tapers the board, if there is a curve it follows the curve.

I was leery of jointers for awhile because I had erratic results. Still leery of them because they can be very dangerous.


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## AESamaan (5 mo ago)

Thanks to everyone that has answered.

I am looking at YouTube vids…. And it seems like I am just magnifying an existing defect in the lumber.

At least I hope so…. But will check setup.


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## Unknowncraftsman (Jun 23, 2013)

If the outfeed table is too high it will caused a belly. Try lowering the outfeed table and start with a different board. The one with belly is too far gone. If you outfeed table is fixed and cannot be lowered like the infeed get rid of that jointer.
Good Luck


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## StevoWevo (Jul 21, 2021)

Good time for practice. Draw a straight line from corner to corner on the convex edge and start taking very light cuts working from the center section out. By this I mean joint the center 4" on the first pass then maybe the center 8" on the second pass and so on. Don't take anything off the very ends until your edge is concave or very close to concave. Reference your straight line so you can see exactly what's happening with successive passes.
I always try and edge joint the concave edge but sometimes that's not an option. All this assumes you have your settings correct. Best of luck


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## controlfreak (Jun 29, 2019)

I would start by making a gauge to insure you blades are dead even with the outfeed table. I took another LJ members idea and attached a dial gauge to a 1×2 x 3 block. I tried the pull a stick forward method but no luck. After setting with a dial gauge I saw perfect results. I did a search and made one similar to the bottom picture here


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## yamato72 (Apr 5, 2021)

I'll pile on here. Assuming your jointer is properly setup (outfeed table aligned to TDC of cutterhead), and you are using the correct technique (pressure on outfeed table), the difficulty is due to attempting to joint the "belly" edge. Joint the board "belly-up" (straightening the cup out of the opposite edge) then rip the "belly" edge off at the table saw.


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## gdaveg (Aug 1, 2020)

+1 what Loren & Yamato said. Rip off the belly side on TS.


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## yamato72 (Apr 5, 2021)

<deleted>


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## AESamaan (5 mo ago)

So I tested three or four of the blades with a straightedge…. And they were right there. The blade would slightly kiss the bottom of the straightedge.

I also made sure to put pressure on the outbound side…..

BUT STILL!!! It's still creating a belly on that board.

I did go and do a very slow cut on a band saw since I don't have a table saw…. Tried again, and got the same belly

I gave up and ripped it again and sanded it with a block. The pressure from the clamps was enough to squeeze out any difference between the two boards.

I officially hate jointers. They are the product of the Devil!


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## gdaveg (Aug 1, 2020)

Jointers are hard to learn. If you know an experienced woodworker have him show you how to use the machine.

You have to pay attention to where you apply pressure in relationship to the outfeed table, direction of bend in the board you are working. And is the board cupped.

It is much easier to start your build with straight and square lumber. Otherwise you fight the flaws the whole project.

You might lower the depth of cut and try that. No more than 1/16" in a single pass. I tend to go a smidge more than 1/32" per pass unless the board is badly twisted.


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## SMP (Aug 29, 2018)

I used to have similar issues. A jointer by nature will follow a belly and just make it worse. I adopted a hybrid woodworking approach. I can now joint a board by hand with just a single hand plane no problem. It takes some practice. However, even if you are unskilled and have a sharp jack plane, you can VERY quickly take the belly out of that board and make it slightly convex. The way my jack plane is setup it takes me like 10 seconds. Then the jointer is easy mode. This IMO is by far the fastest way. Way faster and more controlled than either all power or all hand, plus safer as less time on the jointer.


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## Unknowncraftsman (Jun 23, 2013)

The best and most accurate way to set outfeed table to the top of the cutting circle is by letting the cut determine the height.
First lower the outfeed below the height of the infeed.
Turn on machine and take a cut on a fairly straight board when 3 or 4 inch is hanging over the outfeed stop. Turn off machine.
Raise outfeed until it touches or even a slight gap remains between the table and board the thickness a sheet of paper.
If you get snipe on the trailing end remove slight gap.
Good Luck


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## redlee (Apr 11, 2016)

> So I tested three or four of the blades with a straightedge…. And they were right there. The blade would slightly kiss the bottom of the straightedge.
> 
> I also made sure to put pressure on the outbound side…..
> 
> ...


Made me laugh, they can be a frustrating beast to tame but once you get it they are invaluable.
Dont give up !!!
The Devil made me do it.


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## Unknowncraftsman (Jun 23, 2013)

If that a jointer with a fixed outfeed and inserts knives send it back and get your money.


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## MadMark (Jun 3, 2014)

This is why I don't use a jointer. I straighten the edges on the TS and flatten with the Planer.

I often resaw up to rough 2×6's on the TS and plane from there. I don't buy corkscrew lumber or tree falls and so I have excellent results without a jointer. Since I don't often need really long pieces there's no point in trying to joint or even TS edge an 8' piece. I rough cut according to the saw schedule and get the lengths manageable. Proper layout can often eliminate a dog leg or other warp. Then the TS/planer combo works like a charm and takes less skill (as you are finding) than a jointer on most runs.

I *DEFY* anyone to look at a finished piece (yours or mine) and say "Look here! He used a TS/planer instead of a jointer!"


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## AESamaan (5 mo ago)

This is for bookmatching two halves of a guitar body.


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## MadMark (Jun 3, 2014)

That has nothing to do with jointing the edge. A clean rip line on the TS will give you a book matchable edge.


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## redlee (Apr 11, 2016)

> This is why I don t use a jointer. I straighten the edges on the TS and flatten with the Planer.
> 
> I often resaw up to rough 2×6 s on the TS and plane from there. I don t buy corkscrew lumber or tree falls and so I have excellent results without a jointer. Since I don t often need really long pieces there s no point in trying to joint or even TS edge an 8 piece. I rough cut according to the saw schedule and get the lengths manageable. Proper layout can often eliminate a dog leg or other warp. Then the TS/planer combo works like a charm and takes less skill (as you are finding) than a jointer on most runs.
> 
> ...


I dont think anyone will deny that there is alternate ways of achieving good results.
Jointers have been around for about 140 years , reason being they work.


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## controlfreak (Jun 29, 2019)

Checking with a straight edge was close but not close enough for me. The dial gauge let me make the 1000th of an inch adjustments to get dead even. I had the same problem as you. If the infeed and outfeed tables are not coplanar that can be a problem too but you will need a high end straight edge to check and adjust, a level one again is not good enough.

After I got mine dialed in I found that with practice I could use a jointer plane to do the same and got rid of that space hog. Shop is much quieter and less dusty too.


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## tvrgeek (Nov 19, 2013)

Outfeed should be just a half-hair lower than the cutters as the wood compresses slightly under the blade. Less than paper. You fine tune by cutting wood, not with a strait edge.

There are very good video's on tuning a jointer. Many the tables are not in parallel planes and the ways need a shim. Good news is you only have to do it once if you have a helical head.

There is no reason for a jointer to give a belly or cup.


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## mamell (Dec 24, 2015)

Jeeez..Lucky me..My ancient old HEAVY Dewalt joiner doesn't even have an adjustable outfeed, just the infeed and I keep it just a few hairs lower than the blade..Took me a few days to figure out how to adjust the blades and clean the gunk out of them..Old joiner.. The only weight I put on the infeed is just getting it (board) started. After a few inches my weight's on the other side and i hope the door is open before i start..(limited space..


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