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View Full Version : Jointer tables - how close to parallel?



Jeff Cord
08-16-2006, 12:33 AM
I just set up a new jointer and am in the process of destroying some wood (I mean learning how to joint wood).

I'm working with some cheap poplar so I'm more interested in learning at the moment so my quest is to be sure the problem is with technique (or lack) and not equipment. I'm leaning toward operator error.

However, to elimnate an equipment problem I took out my straight-edge (LV 38" aluminum) and measured the flatness of the tables. They seem OK, each table is within .003" of flat (which could reflect the accuracy of the straight-edge as well as the tables).

I then measured the parallelness (OK, so it's not really a word) of the tables in relation to each other.

Now since each table is not "perfectly" flat how close should the two tables be aligned to each other?

I've watched my dogs chasing their tail.
I can imagine the two of them shaking their heads watching me try to align these two tables thinking "he's never going to get it".

When dealing with these tables how close is close enough?
thanks,
Jeff

Chuck Wintle
08-16-2006, 6:58 AM
Just for my own education just how many ways can a jointer be off? :D

David Eisan
08-16-2006, 7:19 AM
There is only one thing that matters, does it work?

Take two long'ish boards (5'?), face joint them then edge joint them. Slide them together on top of your table saw. Do the edges meet nicely? If so, you are done.

David, who has grown out of his anal phase...

Tony Falotico
08-16-2006, 7:40 AM
Jeff, I am by no means a jointer expert, but will relay some of the learning curve I went through setting up mine a few years back.

It IS very important that the infeed / outfeed tables be as near parallel as possible ....... any angle between the two will be reflected in your work piece.

Also, make sure the tip of the knives line up with the top surface of the outfeed table, if they are above or below you will get a bow in your edge.

I didn't have trouble with 'parallelness', but I did struggle with the knife height issue. It took me a while to learn the 'feel' of the jointer, it does take some finesse, but once I got it I began using it often.

Good Luck

FWIW: Mine was a floor model when I bought it, so it took some time to re-adjust everyone's 'playing' with it.
I destroyed a good bit of wood before I got it right..............

Tony Falotico
08-16-2006, 7:43 AM
Just for my own education just how many ways can a jointer be off? :D


infeed / outfeed table not parallel to each other
knives set crooked in cutter head, or unevenly ground
knife tip not aligned with top surface of outfeed table
fence not perpendicular to infeed / outfeed table

Julio Navarro
08-16-2006, 8:04 AM
Just my hummble opinion but isnt he asking if the tables are level to each other, not parallel, in a jointer the idea is that the infeed be a bit lower in relation to the outfeed, but they must be level in relation to each other.

am I right, perhaps I just missread the question or we are talking about the same thing ?

Robert Mickley
08-16-2006, 8:26 AM
Just my hummble opinion but isnt he asking if the tables are level to each other, not parallel, in a jointer the idea is that the infeed be a bit lower in relation to the outfeed, but they must be level in relation to each other.

am I right, perhaps I just missread the question or we are talking about the same thing ?

I can make this clear as mud. If both tables are set to ths same height, you should be able to lay a straight edge across both tables and not have any discernable gaps. what happens is some times the outfeed table runs uphill or downhill in relation to the infeed table.

If it runs up hill as your jointing a board the center of the board will climb away from the cutter head as the leading edge gets closer to the end of the outfeed table. If it runs downhill as your jointing a board a gap will appear atthe leading edge. At some point as your jointing a board it will rock down onto the outfeed table. Either way the more passes you make you the more screwed up the board will get.

Once they are lined up you lower the infeed table to get your depth of cut. I just went through this with the new to me jet.
when I layed a straight edge across the tables I had about 3/32 gap at the end of the outfeed table. I ended up putting about a .006 shim in the botom edge of the ways to get it up to snuff

Al Willits
08-16-2006, 8:40 AM
Just went though most of this, and imho, you can't be anal about setting up equipt, especially when all that is required is your labor.
This all depends on what your idea of accurate is, and what efforts you'll use to get there....your choice

I'm assuming what he means is, when both tables are brought up to the same level, they indeed should be parallel, they should be both left to right and front to back even (if that makes sense).
I can't help ya with .003 and whether that's ok or not.

I'm discovering there is a leaning curve to getting well cut wood off these things, pressure on the wood on the infeed side at first, then transfering to the outfeed side seems to help, and not forcing the wood though the jointer along with not stopping all help.
Going to fast seems to leave a cut that reminds me of a blade chattering on metal.

I did a search on jointers and planers and have picked up a lot of info...maybe to much, but it has helped me. :)
Good luck.
Al

Jim Becker
08-16-2006, 8:43 AM
Perfectly parallel should be your goal. Any deviation, even if very small, will affect your ability to get boards flat and straight. Remember, a small deviation is magnified over the length of the tables. Typical symptoms of "out of parallel" are boards turning into wedges when edge jointing or becoming more thinner on one side than the other when face jointing. You also want to deal with this adjustment before you set your outfeed table relative to your knives...or even setting the knives.

Jeff Cord
08-16-2006, 10:57 AM
Just as some follow up info.

The outfeed table is dead-on parallel to the cutter, the cutter blades appear to be set correctly (the joiner included a knife setting jig that I used to confirm this).

The outfeed table is set to the correct height relative to the blades.
My biggest issue is the infeed table relative to the outfeed table.
I did face joint a long (8') piece of poplar and got the lead end thinner than the tail end (it turned into a long wedge)
However, I suspect I was pushing down too hard (flexing the bow out of the wood) and I didn't rough-cut the wood to length before jointing to lessen the bow (and joint shorter pieces) before jointing.
Thanks again,
Jeff

Jerry Olexa
08-16-2006, 11:28 AM
I'm in process of evaluating and rating the various jointers to buy.. After reading this, I wonder if these detailed adjustments will get to be a recurring pain....Patience is not a strong virtue of mine....Only musing. Just a weakness of mine... Joint away

Jim Becker
08-16-2006, 12:15 PM
Jerry, it SHOULD be a one-time adjustment, although prudence suggests one check it from time to time, perhaps annually.

Chris Padilla
08-16-2006, 12:22 PM
Yes, even cast iron moves, sags over time. When you need to joint that piece of curly quartersawn bubinga that just cost you $$$$s, you may wish to make sure that jointer is "dead nuts" on! :)

Al Willits
08-16-2006, 2:48 PM
Jeff, remember I'm a newbie at this but it seems your at about where I am now, did you bring the in and out feed tables level with each other and use a long straight edge to make sure the table are not bowed/warped/to high-low at either end of the table as compared to the rest of them?

May want to just run another long test board though, letting the jointer do all the work and see what happens, if still tapered, maybe check the tables for straightness/levelness to each other.....that make sense???

Al

Jeff Cord
08-16-2006, 3:17 PM
I used a 38" edge to test.
But since each table is not perfectly flat (up to .004" off) I'm finding it hard to tell if the tables are parallel or if what I think is out of parallel is really the table not being perfectly flat.

Gary McKown
08-16-2006, 3:57 PM
Julio and others - not to be anal about it, but the tables should be parallel to each other no matter what. If at the same height then they would also be coplanar.

Since the tilt of the infeed on my old Craftsman varies with height (even after shimming the ways as best as possible), I set the table about 1/32" lower (and leave it there), then use a straight edge and feeler gauges to get it parallel to the outfeed.

Jeff Cord
08-16-2006, 11:01 PM
I spent some more time tonight and I think I now have the tables parallel to each other.
Adjusted the outfeed height until I got no snipe, ran a 5' 2 X 6 through and got a flat straight face with straight (and 90-degree) edge so I'm happy.
Thanks for the help.
Jeff