Jointer making wedges?????

[DaveO]

Probably the idiot behind the machine, but my Ridgid jointer is making wedges. I face jointed some cherry stock this weekend and it came out thinner on the front than on the back. I apply pressure to the infeed table until halfway through the cut and then shift the pressure to the outfeed table. The cut is very smooth and flat, and I ended up surface planing the stock down quite a bit which made both sides paralelle. But I would like a better result off the jointer, in case I am trying to spare wood. What am I doing wrong, or is my machine out of alignment. Thanks for ya'lls advice. Dave

 

[ChrisC]

Dave,

I wouldn't be concerned with that if you are only face jointing. Because they can be warped, twisted, etc.

BUT, if you are making "wedges" on edge joints, then that is a problem.

It could be tables not co-planer, blades out of alignment, and even dull blades.

 

[DaveO]

I haven't noticed it when edge jointing, but I haven't checked for that. The knives are sharp and as far as I can determine well aligned. Tables being co-planer and possibly knife alignment, might be the issue. Any good tips on how to test for those issues? I have a sinking suspicion that it is the tables. Dave

 

[Steve D]

Maybe some others have some secrets but a really high quality straight edge that is long enough to span a good portion (ideally all) of both beds is all I'm aware of to use. Shine a light and use feeler gauges to determine the degree of mis-alignment.

 

[ChrisC]

Use a straight edge( at least a 4' level or metal rule) and see if your tables are flat(co-planer) from end to end. If so, then use that same straight edge to see how your knives are in line with the outfeed table. The knives should "just" touch the straight edge. Check all three knives, and the whole width of the table.

Hope this helps.

 

[chris99z71]

I've never done this, so I may be talking from my rear facing orifice, but I'd think it also important to check across the whole width of each blade as well, not just one point. Am I right?

 

[Monty]

How long is the piece of wood you're trying to face joint?

 

[Joe Scharle]

One of the most vexing jointer problems I ever had was similiar to what you describe. First though, I never realized just how much pressure I applied to the stock when I was jointing until my neighbor, who worked one summer in a furniture plant, pointed it out to me. He said that if I had to do this for a living, my arms would give out before lunch!
Anyway, my problem was caused by a little ball of sawdust in the dovetail slide, letting the infeed table 'rock' under pressure. Up until then I had never pulled the infeed table off for cleaning and waxing.
Also, take the lash out with the gib screws.

Good luck,
Joe

 

[gator]

If I remember correctly (and at my age memory does go) from 'Jointer 101', your outfeed table is too high.


George

 

[DavidF]

My 2 pen'th would be out feed table two high at the far end. Checking the knife/outfeed alignment would show it as good. With the OF up at an angle you are planing "up hill" and progressivly lifting the board off the knives.

 

[DavidF]

Gator - if the OF was just too high the wood would just "bump" into the table after it had been passed through the knives.

 

[DaveO]

Well, I brought home a 4' alluminum ruler from work today, it's the closest thing to a straight edge I can get without going throught the trial and error of the MDF and screws, three board method. We'll see what it tells me. I do think that the end of my outfeed table could be a little high. Thanks for everyones advice. Soon I might need more on how to fix my possible problem.

Dave

 

[Jonz]

Dave if that doesn't work I have a 4' aluminum level you are welcome to use any time you need it.

 

[DaveO]

OK, it must be my techinque. With that 4' ruler and a feeler gauge, I wasn't able to get anything greater than .002 underneath it at any point. Where the .002 gauge would go underneath the "straight" edge wasn't in any particular area like the end of the table. It would slide underneath at random points often only a few inches apart. That makes me think that my "straight edge" isn't very precise, but my jointer is set up pretty well. I also checked the blades and they were consistantly less than .0015 above the outfeed table. Not too bad for straight out of the box set up from Rigid. So I come back to my techinque, and advice on that?

I did discover with the straight edge test that my miter station needs some shimming. My CMS is built into my "workbench" and one side isn't coplanner to the main table of the CMS. That eplains some of the less than perfect results I've been getting while cross cutting and mitering. A fairly easy fix, just a few folds of card stock between the bottom and the ledge it is sitting on.

Dave(finally straight:lol: :lol: )

 

[DavidF]

Hi Dave,

When you transfer pressure to the OFT where are you pressing? Are you only then pushing the wood through and not pressing it down onto the IFT? I put pressure just forward of the knives and use a hand over hand movement using two rubber faced push blocks, that way I don't touch the trailing end of the wood at all. What DOC are you taking? I almost never take more than 1 - 1.5mm (1/16"). If the piece is warped or cupped, put the concave side down.

If nothing else works then let me know and maybe I can come round and have a look.

 

[Jonz]

I put pressure just forward of the knives and use a hand over hand movement using two rubber faced push blocks, that way I don't touch the trailing end of the wood at all.

This is the exact technique I use as well.

 

[DaveO]

That is the techique I thought I was doing but there is a good possiblity that I did apply some pressure to the IFT during the second half of the cut. I recall the board not moving very well cause my rubber push pads were sliping a little. My depth of cut is usually only 1/16" or less. This is the 3-4th time I've face jointed, probably need some more practice, and need to wax my tables again. I will probably be doing a little work on the jointer tonight, depending on the condition of the wood I am getting after work. I'll really focus on proper techique and see if that is my prob. Thanks for everyones advice. Dave

 

[Mountaincraft]

Every one will make wedges with a jointer if flattening one face of the board, pushing it through the same direction every time, especially if the board touches at the ends, rather than middle. After getting a foot or so onto the outfeed, push board only by putting just enough pressure to move it on the outfeed side only. Keep swaping ends, looking to see which end you want the most off. Oddly enough, I set the board concave side down and just nibble off the ends to start. Once the knives maintain contact throughout the run, I quit swaping ends and make a few runs just to even the surface. I keep my jointer set at 1/32 in. and live with the extra passes. Prevents many problems. Swapping between planer and jointer will help some, too. Don't make a wedge then try to plane it, that could get ugly.

 

[Ozzie-x]

Yes, swapping the ends of the board may be the solution. Swapping the ends will "cancel out" any discrepancies in the adjustment or cutting. That's the technique I use especially on face jointing rough lumber. I sometimes work up some very ugly, twisted, cupped, warped, downtrodden (you get the picture) rough sawed lumber and never have any wedge problems.

 

[Bernhard]

Dave,

...maybe the wedge is part technique and part misalignment
Some of the minor gods of furniture making preach to transfer all pressure and stock feeding to the outfeed table as soon as enough length of stock is on the OFT to place a push block on it.
Did you check the tables across diagonally? Did you check the tables under load (i.e. applying pressure while checking)?

I have a 6' certified straight edge; your welcome to use it. I actually bought that thing out of desperation when I couldn't figure out why my my jointer would not joint. My jointer was out of plane diagonally.

..my 2 cents. Hope you get the problem solved.

Bernhard