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What am I doing wrong with my Jointer?

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Forum topic by PeteK posted 10-15-2017 07:31 PM 1732 views 0 times favorited 41 replies Add to Favorites Watch
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PeteK

27 posts in 451 days


10-15-2017 07:31 PM

Hello all. Rookie woodworker here. I just got this Delta 6” Benchtop Jointer and I am attempting to make a flat panel out of 1×4 boards. They were already pretty close to flat on the edges but I wanted a no gap, seamless panel. But it seems the more I run the boards on the jointer, the more convex they become. So like when two boards are up against each other, there is a gap at the ends. What am I doing wrong? I am applying pressure on the outfeed side as I push through. I tried deeper cuts and shallower cuts but I keep getting further and further away from being flat. I’m confused.


41 replies so far

View PurpLev's profile

PurpLev

8531 posts in 3458 days


#1 posted 10-15-2017 07:39 PM

you might be just suffering from snipe (Edges getting overly cut), how is the center of the boards? flat and true?

usually you want to joint boards longer than the final result (if you want 30” final boards, you would want to run boards that are 32”+ long so that you can trim the ends and get you true 30” flat boards at the end)

-- ㊍ When in doubt - There is no doubt - Go the safer route.

View a1Jim's profile

a1Jim

116492 posts in 3387 days


#2 posted 10-15-2017 07:44 PM

Your problem is that your trying to joint the convex side of the board and it rocks from one end to the other if the other side is straight then take it to the table saw and put the straight side up against the fence and take just enough off to remove the convex bump then joint as necessary .

-- http://artisticwoodstudio.com Custom furniture

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MrUnix

5896 posts in 2009 days


#3 posted 10-15-2017 07:44 PM

Here is a good place to start: Jointer Problems, Causes & Fixes

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

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Loren

9546 posts in 3457 days


#4 posted 10-15-2017 07:48 PM

Before you start, put a straight edge on
each edge to be jointed to determine where
to remove stock. An edge will often be
either too hollowed or too bellied to straighten
in one pass on the jointer. If the edge is
hollow, partial passes from each end remove
the excessive hollow. If the edge is bellied,
partial passes in the center of the board
remove the belly. When you can hold the
straight edge up to the edge and it is close
to straight, then one pass will make it straight
if your technique is good.

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a1Jim

116492 posts in 3387 days


#5 posted 10-15-2017 07:50 PM

Good to see your post-Sharon I guess I’ve missed seeing your post lately.

Lorens approach works great too.

-- http://artisticwoodstudio.com Custom furniture

View Kirk650's profile

Kirk650

504 posts in 558 days


#6 posted 10-15-2017 09:06 PM

When running the board edge across the jointer, press down on the middle of the board. That will help with getting the edge flat, or as I prefer, slightly convex.

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PeteK

27 posts in 451 days


#7 posted 10-16-2017 01:24 AM



Your problem is that your trying to joint the convex side of the board and it rocks from one end to the other if the other side is straight then take it to the table saw and put the straight side up against the fence and take just enough off to remove the convex bump then joint as necessary .

- a1Jim

Well, that is exactly what is happening, but I still am not sure how I got to there. As I said, it was pretty close to a flat edge to begin with and the more I ran the board through the jointer, the more convex it became.

I thought maybe snipe, but I always thought that would be more pronounced.

View Gaffneylumber's profile

Gaffneylumber

98 posts in 638 days


#8 posted 10-16-2017 02:33 AM

Have you checked to make sure your outfeed and indeed tables are coplaner?

-- Grayson - South Carolina

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PeteK

27 posts in 451 days


#9 posted 10-16-2017 02:39 AM



Have you checked to make sure your outfeed and indeed tables are coplaner?

- Gaffneylumber


Well, they are both level. I’m not sure the outfeed is adjustable.

View RobS888's profile

RobS888

2301 posts in 1655 days


#10 posted 10-16-2017 02:49 AM


Have you checked to make sure your outfeed and indeed tables are coplaner?

- Gaffneylumber

Well, they are both level. I m not sure the outfeed is adjustable.

- PeteK


How hard are you pressing down? If you push a board flat it will come out the same shape, but with a shave. I made some bananas when I first tried jointing. It is more of a guiding operation not a forcing operation.

-- I always suspected many gun nuts were afraid of something, just never thought popcorn was on the list.

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PeteK

27 posts in 451 days


#11 posted 10-16-2017 03:49 AM


Have you checked to make sure your outfeed and indeed tables are coplaner?

- Gaffneylumber

Well, they are both level. I m not sure the outfeed is adjustable.

- PeteK

How hard are you pressing down? If you push a board flat it will come out the same shape, but with a shave. I made some bananas when I first tried jointing. It is more of a guiding operation not a forcing operation.

- RobS888and

Was pushing kind of hard. I guess i dont really know the proper pressure to push down, but it makes more sense to just sort of guide through

View AlaskaGuy's profile

AlaskaGuy

3523 posts in 2119 days


#12 posted 10-16-2017 05:12 AM

How long are the 1×4’s ?

-- Alaskan's for Global warming!

View Andybb's profile

Andybb

523 posts in 413 days


#13 posted 10-16-2017 05:28 AM

I just spent an evening dialing in my 6” Delta. I’m no expert, but here’s what worked for me.

First, make sure the jointer is setup up properly to eliminate anything but human error before moving on.

The outfeed table is only adjustable with shims.

1. When the infeed table is as high as it can go it should be level with the outfeed table. Also make sure it’s level on the back (fence side) and front side (switch side). I had to shim the outfeed table up just a touch by removing the 4 bolts and putting a shim under the front 2 bolts.

2. Then, make sure the knives are adjusted correctly. Some say that when you rotate the knives with a straight edge on the outfeed table they should pull the straight edge forward 5-7mm. That always gave me snipe at the tail end of the board. This was caused by 2 things. One being that the infeed table was slightly higher than the outfeed. The other reason was that the blades were adjusted to pull the 7mm. It wasn’t until I saw something here that said this was incorrect and that the knives should be adjusted so that they are flush with the two tables. Use the little latch that flips up which will lock the blades in their highest point of travel. Your straight edge should glide across the tables and blades smoothly without touching the blades.

3. Then, make sure your fence is 90 degrees to the tables.

After doing those things in that order all my issues went away and I could work on my technique, which is just as important as the above but can’t be done until the machine is trued up.

Start with scrap wood that you know to be flat and is about 5” inches wide. With the tables and blades aligned and set to zero it should pass over the blades and remove nothing. Then adjust it until you can just hear it kiss the wood. Then back it off ever so slightly until you hear nothing again. Loosen the screw on the indicator and set it to zero then tighten it. Use chalk or pencil lines on the bottom of the piece and slightly adjust the blade height so that it takes off only a thin sliver of wood. The pencil lines should be evenly removed across it’s width. If they are not then your blades aren’t aligned. Fix that. Then, if you get snipe it means that the board is dropping off of the infeed table onto the blades and they, the tables, are not coplanar. Go back and fix that.


Now you can work on your technique. Put pressure on the piece as you move it across the infeed table keeping very slight pressure on the outfeed side.

Then follow Loren’s directions


Before you start, put a straight edge on
each edge to be jointed to determine where
to remove stock. An edge will often be
either too hollowed or too bellied to straighten
in one pass on the jointer. If the edge is
hollow, partial passes from each end remove
the excessive hollow. If the edge is bellied,
partial passes in the center of the board
remove the belly. When you can hold the
straight edge up to the edge and it is close
to straight, then one pass will make it straight
if your technique is good.

- Loren

Like I said, I’m no expert but it worked great for me. When I set the dial to 1/32 and used my calipers it took off exactly 1/32. Flat boards, no snipe.

-- Andybb

View rwe2156's profile

rwe2156

2684 posts in 1290 days


#14 posted 10-16-2017 01:07 PM



When running the board edge across the jointer, press down on the middle of the board. That will help with getting the edge flat, or as I prefer, slightly convex.

- Kirk650

I wouldn’t do this ^ especially when face jointing all you’re doing is simulating a planer.

One mistake I made as a newbie was putting to much down pressure on the wood over jointer head. The only pressure should 1) over the outfeed table and 2) behind the cutterhead on the infeed (which is more to keep the wood moving than push down on table).

I recommend using a push block with heel rather than a standard push block, which often makes you put excessive down pressure right. You don’t want to flex the wood you want it to take off the high places. This is especially important when face jointing where the wood flexes much more.

-- Everything is a prototype thats why its one of a kind!!

View jonah's profile

jonah

1374 posts in 3108 days


#15 posted 10-16-2017 01:50 PM

Ditto. You want to be pushing down very hard on the outfeed side to make sure the wood registers off that surface. That will make the board conform to that (flat) surface, rather than bowing up and down as your pressure changes.

You never push down right over the cutterhead.

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