Woodworking Talk banner

1 - 20 of 28 Posts

·
Registered
Joined
·
1,183 Posts
Discussion Starter · #1 ·
Is a 38" straight edge long enough to check tables for co-planar on a 8" jointer with 72" bed? I am looking at the Lee Valley 38" Aluminum Straight Edge for $39.50 + $12.50 shipping. Yes I would love to have the 50" one, but not sure if the extra 12" is worth the extra $50. Not sure why it costs $89, but I would prefer not spending the extra bucks. So is 38" enough?

Yes if I hit the lotto, I would get the biggest size Starrett I could. I am poor and don't want to spend more than need be.

Thanks
Paul
 

·
Registered
Joined
·
1,183 Posts
Discussion Starter · #3 ·
I have a few 48" levels, but don't think that the bottoms are truly flat enough to use for jointer set up. Although I am no expert on jointer set up and have been struggling for a month. A new level might be flat enough, most at the BORG seemed cheaply made though.
 

·
Registered
Joined
·
26,896 Posts
I have a few 48" levels, but don't think that the bottoms are truly flat enough to use for jointer set up. Although I am no expert on jointer set up and have been struggling for a month. A new level might be flat enough, most at the BORG seemed cheaply made though.
What is it you are trying to set up? I assumed you wanted to check to see if the rear table is straight with the front table.
 

·
Registered
Joined
·
1,183 Posts
Discussion Starter · #5 ·
Yes, want to check for co-planar. Maybe I am over thinking it. I have watched the wood whisper's video on jointer set up and he is using feeler gauges and checking 1000th of inches. I went a played with the dovetail gib screws and now I think my outfeed table is out of whack, let alone trying to get it co-planar with the infeed. I am at a loss trying to get this thing set up. I am at the point where I would possibly call in a repair man, if there were such a person, to come in and set it up correctly. Before I started messing with it, it seem to work fine, until one day, it wrecked a table leg I was making. Seems like it was cutting on an angle all of a sudden, from front to back to the fence. Now it is a mess.
 

·
Registered
Joined
·
26,896 Posts
It's pretty rare for the jointer tables to get out of sinc with each other. Unless yours has been damaged in some way or another I would just make sure the knives were properly installed. I just lay a 6" steel rule edgeways on the rear table extending over the knives. The knives should barely touch the ruler. If you get all of the knives lined up that way you shouldn't have a problem.
 

·
where's my table saw?
Joined
·
28,616 Posts
I use a 48" level

Yes, want to check for co-planar. Maybe I am over thinking it. I have watched the wood whisper's video on jointer set up and he is using feeler gauges and checking 1000th of inches. I went a played with the dovetail gib screws and now I think my outfeed table is out of whack, let alone trying to get it co-planar with the infeed. I am at a loss trying to get this thing set up. I am at the point where I would possibly call in a repair man, if there were such a person, to come in and set it up correctly. Before I started messing with it, it seem to work fine, until one day, it wrecked a table leg I was making. Seems like it was cutting on an angle all of a sudden, from front to back to the fence. Now it is a mess.
Those screws just need to be snug enough to prevent the tables from shifting. I doubt if you have changed the relationship of the tables by loosening them. :no: Start with the out feed and register off the cutterhead, by backing the infeed down and away. The outfeed should be parallel with the top of the cutterhead, at a point in between the blades. Once you get that good, slide the level across and see how the infeed table looks and if it is parallel to the outfeed and cutterhead barrel.

Let us know what you find. I use the aluminum level because it will stand up on the tables without falling over. You must check at both ends of the cutterhead for parallelism to the outfeed. The only time you will need to shim the gibs is to correct for coplaner, and I would just work with the infeed for that. It rarely goes out of whack, so I wouldn't worry too much at this point. :no:
 
  • Like
Reactions: Paul W Gillespie

·
Registered
Joined
·
473 Posts
Sorry to hear you're not making sawdust. Long bed jointers are prone to saggy tables, often from wear and gib adjustments. Since you loosened the gibs, and your jointer relatively new, I'd adjust the gibs. Start with the outfeed table. Use a jack and a piece of 2 x 4 and apply pressure/support on the outboard end of the outfeed table. Loosen the locknuts, and back off the gib screws until you feel no tension on the screws. At this point you should be able to turn them by hand if you wanted. Now give the jack a pump, lifting the base just slightly off the floor. Now just snug the gib closest to the cutter head, and while holding the gib screw with your wrench tighten the locknut insuring that the gib screw doesn't turn. Relax the pressure and snug the middle and bottom screw. Pull out the jack, double check and lock the middle screw, and finally the bottom screw. Next, lower the OUTFEED table 1/2 - 1 turn. If the hand wheel is a slightly difficult to turn that is okay, because once set the table is locked and never moved. Do not loosen the top gib because the table will droop. Repeat for the infeed table, but the gibs need to start snug and backed off ever so slightly if needed to allow the hand wheel to turn with just a little friction as it did when you got it. Resist loosening the top gib screw too much or the table will droop.

Now to dial in the jointer, find a 3 - 4 foot long board and set your infeed table to make about a 1/32 - 1/16 inch cut. Place the straightest edge, or slightly concave edge on the infeed table, start the jointer, then proceed to cut. Stop feeding the board once 1 - 2 inches are over the outfeed table. Shut the jointer off. Now slowly raise the out feed table until the table is almost touching the cut end of the stock while sliding it over the cutterhead and watching as the end of the board starts onto the outfeed table. At this point I'd be looking for less than a sheet of paper clearance. Now make a full pass, or 2. The edge should be very nearly straight. If it is, great. In all likelihood you'll have a very small snipe at the end as the board drops off the end of the infeed table to the very slightly lower outfeed. Now hold the edge of the board on top of the clean outfeed table. Get at eye level and you should be able to see if the edge sits perfectly flat on the table. Run a second board and mate them to see how they fit. Any errors will be doubled.

Finally, if it's perfect, you're done. In all likelihood you'll see a small snipe at the end thus showing a gap. That is what I was going for, as your last adjustment you'll want to raise the outfeed table against gravity thus putting tension on the mechanism. (Never back off an adjustment on any machine as your final adjustment.) As needed incrementally make very small adjustments raising the outfeed until it's perfect. Go too far, lower it back down and start over again. When set, lock the table and don't use the outfeed hanwheel. (Some shops take them off once set.)

Hopefully it should be cutting well at this point. If there is a slight gap in the middle of the joint, that means the table(s) are still a bit droopy. But wait! If it's just a couple of thousands, you just made a spring joint that once clamped will have the glue joint forcing the ends together. Almost every split I see starts at the end, and you've got the whole joint stopping that. (my preference).

Just an FYI, repeated jointing on the same edge will cause a taper to start even on a well set up jointer, especially multiple light cuts. Possible bad news is if your blades weren't installed perfectly parallel to the tables, you'll need to have the fence in the same position every time. I doubt it would cause a real problem face planning if that was the case. (you could always reset the blade heights, took me forever the first time) The above procedure takes me about 15 min tops, lots faster than my typing. Best of luck, feel free to ask.
 

·
Registered
Joined
·
473 Posts
BTW Paul, when you get your jointer working well again, and you are able to joint 2 boards to make a nice fitting glue joint, you will also be able to make a nice straight edge! It may need to be jointed every once in a while, but should straight enough for use in a wood shop.
 

·
Registered
Joined
·
12,950 Posts
Is a 38" straight edge long enough to check tables for co-planar on a 8" jointer with 72" bed? I am looking at the Lee Valley 38" Aluminum Straight Edge for $39.50 + $12.50 shipping. Yes I would love to have the 50" one, but not sure if the extra 12" is worth the extra $50. Not sure why it costs $89, but I would prefer not spending the extra bucks. So is 38" enough?

Yes if I hit the lotto, I would get the biggest size Starrett I could. I am poor and don't want to spend more than need be.

Thanks
Paul
38" is long enough. However, I would never spend over $50 just for a straight edge. If you look in your local hardware/lowes/home depot/sears/etc you will find plenty of 48" ones for far less.

For an instore check of straightness just hold two together and see if there is any daylight between them.

George
 

·
Registered
Joined
·
1,183 Posts
Discussion Starter · #13 · (Edited)
Just to help clarify the problem I was having. I was jointing the overhanging veneer on these legs I was making for a coffee table, to square them up. I noticed that I was getting more taken off the side on the fence, than the side closest to me. By the time I realized it, there was not enough leg left to get it square and still be the correct size. I was figuring that the leg was being cut by knives that were higher near the fence, or the tables were out of whack. When jointing boards for the table top glue up I also noticed that the were higher in the middle than on the ends, opposite of a spring joint. This could have been user error, but don't think the uneven leg cut was.

When I was squaring up the lumber I also had a tough time getting rough boards, that were just a shade under 4/4, down to 3/4. It seem to always take too much off the side away from me, requiring me to plane them down farther to get a smooth side.

 

·
where's my table saw?
Joined
·
28,616 Posts
The fence must be square to the table...of course you checked?

Looks like a fence issue to me OR the blades are not set parallel across and above the cutter head. If the outfeed table was skewed and you set the blades to that, then you will have the same issue. The cutterhead is the reference to set the tables because "usually" you can't change the cutterhead's position on the machine. Some machines may allow you to shim the bearings on one side....I donno?
 

·
Registered
Joined
·
473 Posts
Looks like a fence issue to me OR the blades are not set parallel across and above the cutter head. If the outfeed table was skewed and you set the blades to that, then you will have the same issue. The cutterhead is the reference to set the tables because "usually" you can't change the cutterhead's position on the machine. Some machines may allow you to shim the bearings on one side....I donno?
Sounds right to me. Another possibility is the stock is not held tight against the fence. The top edge can be seen to be against the fence, but there may be a gap at the bottom that is difficult to see. Try running an edge of 1x stock flat against the fence and check for square.

After the gibs are set, check knife heights at both edges and the center of all 3 blades. in relation to the outfeed table. This will insure they are parallel to the outfeed table and be sure the fence is square to the outfeed. This will insure a 90 degree cut if the face of the stock is held tight against the fence.
 

·
Registered
Joined
·
12,950 Posts
Too bad you did not post that picture in the original post. It would have saved a lot of discussion on the wrong subject.

George
 

·
Registered
Joined
·
1,183 Posts
Discussion Starter · #17 ·
What's the wrong subject George? I still need some kind of straight edge to reset my tables and check for co-planar, since I went messing with them.

I did check the fence and it seemed square to me, before I made these cuts. I also checked the blades and they were a bit off. This led me to trying to reset them. I also think the out feed table is a bit off from the cutter head. Which led me to mess with the gib bolts. I think it might be a combo of all the above causing my problems. Now everything seem out of whack. Hence my wanting info on straight edges.

I will get back in there and start the whole process over again using Old Schools process. I do have a 48" straight edge ruler, Like Hammer 1 links to, just wasn't sure it was flat enough. I also have a couple of 48" levels, but again are the flat enough?
 

·
Registered
Joined
·
473 Posts
Paul, in my last post I suggested checking the fence for squareness at the outfeed table. After squaring the outfeed, checheck the infeed. If it's also square it is very likely the tables are parallel across the width. (It is possible the fence could have a compensating twist) I was trying to get you to adjust the machine which needs to be done so even if you want to buy a straight edge, you'd be ready to use it. I had an Old Delta long bed that the tables had drooped over time about 1/4 inch, and I was able to bring it back to within a few thou with cleaning the ways and adjusting the gibs, and no shimming. The beds cantilever quite a distance and magnify error.

Are you aware that you can make your own straight edge using 3 boards with 3 screws in each board. Quite accurate. Much straighter than a level, and approaching a good steel straightedge. Search it on the web, or I'll outline it for you. The 3 point method is plenty accurate for setting/checking the tables on a jointer. Making a 3 point is also pretty easy. Straightedges are nicer, but not necessary.
 

·
Registered
Joined
·
1,183 Posts
Discussion Starter · #20 ·
Old School did you pull the beds off to clean the dovetail ways? How you cleaned them is something I would be interested in hearing more about, unless I missed it above. I have seen the board and screw straightedge before. I am thinking about buying the 38" veritas, I am just waiting for the LV free shipping event they have around Christmas. If they don't have it, I still might buy it. I have some days off later this week and I will give all the tips a try. Thanks
 
1 - 20 of 28 Posts
Top