I have a Ridgid jointer that seems to be way out of alignment. It seems that when you increase the “bite” by lowering the infeed table, the IF table doesn’t lower in parallel to the OF table. Visually it seemed just slightly of (when checked with a 2′ starrett straight edge).
Determined to get to the bottom of it, I ran a small test. I had a piece of scrap 3/4″ birch plywood, measuing 3.2″ x 15″. I marked 4 points on the wood and measured them with digital calipers. With the bed set to take a 1/64″ bite, I took about 10 passes and remeasured at the same points. Then I took an additional 8-10 passes and measured a third time. The results were abysmal, to say the least. At the “front” end it had removed about 1/2″, but at the trailing end it had only taken about 1/4″. It’s unbelieveable. I can’t see an obvious way to adjust the table to parallel. Does anyone have any ideas?
http://www.yertle.com/images/2005/graph1.jpg
Thanks in advance…
-DJS
“Honey, will you please make some sawdust and track it across the carpet?”
“Yes, dear…”
Replies
Smitty, Don't you have any solid wood? I hate to run plywood on a jointer. The glue is real hard on the knives.
I can't see an obvious way to adjust the table to parallel. Does anyone have any ideas?
Are ther no jack screws or alignment gibs hidden somewhere on the machine? Contact your Rigid tech supprot
I have a Delta 37-195 6" jointer and am basing my comments on it. However I think all of these jointers have similar construction.
The Delta manual describes how to make the tables parallel. It is done by adjusting gib adjustment screws. The infeed and outfeed tables each slide in a way - look for the dovetail ways machined into the castings. For each table there are two ways and one has a rectangular rod (gib) to allow fine adjustment of tightness and parallelism. On the Delta there are three adjusting screws for the infeed table gib, each screw held by a locknut. On the outfeed table there are two.
You will need to unlock the normal locking lever/knob for the infeed and outfeed tables. Then set them both at the same height temporarily while you adjust parallelism. According to the Delta setup manual,
"starting with the lower screw first and as you proceed to the top screw, gently raise the outboard edge of the table that is being adjusted. This will offset any tendency for the table casting to 'droop or sag' and permit the gib to be adjusted to a secure fit."
You must make the gibs tight with no play and your straightedge should show the tables perfectly parallel. If the gibs are too tight then normal height adjustments later will be difficult. Once the gibs are set, tighten the locknuts and readjust the table heights with respect to the blade and lock them in place.
Sounds like one of the gibs wasn't adjusted correctly at the factory. Another possibility is a burr on a gib or the way causing a problem and it would need to be filed off.
One sure way to cut a taper is to make multiple passes on the jointer. Plywood would be worse and would also dull the blades. 1/64" adds even more problems.
Take a longer straight edge. Hold it on the outfeed table so that it extends well over the infeed table, full length if possible. Use a feeler gauge of some type. Set the infeed table height to match the gauge and check front and back as well as the left and right sides. This will tell you if the tables are parallel or twisted. Most likely the jointer is fine but your technique for measuring and use is not.
Jointers and planers don't work well at very small increments. You need enough knife to make good contact and not cause the piece to ride up over the blades, 3/64" would be about the minimum, 1/16" is average. There is a lot more to operating a jointer. When flattening or straightening, place pressure on the infeed table for about 1/3 the length of the material. Switch you hands and pressure to the outfeed table to finish the cut. There are many articles in the archives on setting up and operating jointers. Woodworking processes are not finite like mathematics, too many little variances come into play and miniscule measurements and cuts, highlight the limitations.
I would not run plywood on my jointer, the glue can do a number on the knives. A 3' length of clear pine would make a better test piece. If you make many passes with any material, you will get inconsistent results.
You might find it helpful to get a book on the basics of machine tuning, see here http://www.cambiumbooks.com
I work on machines and have rebuilt many jointers over the years and I am puzzled over your methodology in analyzing the problem. Plywood is not a good choice to use. Also sharp knives. You don't even mention feeler gauges in your use of the straight edge. Your incremental material problem can be as simple as the knives being off slightly from the height of the outfeed table. From your description it sounds as if the outfeed table is slightly higher than your knives which produces the taper you speak of. I suspect your jointer isn't as off as you think.
You all are making some good points.
It is also possible, as was suggested, that the feeding technique is causing the error buildup. Assuming both tables are in perfectly parallel planes, the board needs to be held flat against both tables at all times. This is accomplished by distributing the downward pressure on the board so that it is applied to both tables evenly and consistently.
I have a Ridgid jointer that seems to be way out of alignment..
Just me so take with a grain of salt.. Well, maybe a box of salt..
I have a Ridgid jointer that seemed to be way out of alignment.. AND.. It was ME!
Dang.. I got tapers.. Sometimes.. I was NOT transferring pressure on the stock to the outfeed table when the stock passed the blades..
Only jointer I have so.. Not sure but sure seemed to help ALOT!
I checked the tables when I first got it and infeed and outfeed were almost perfect alignment.. I have a 6 foot stainless certified straight edge... It is about 1/4 inch wide with a knife edge.. We use to use it to set LASER beds with for out tests... So I know it is straight!
Thanks all for the posts.
I am definitely transferring pressure- on the 15" sample, I simply held down both ends, one hand on each end, and moved it across the table, so the pressure transfered with the wood.
On the question of feeler gauges, I didn't use any, but I could visually inspect and see a slight increase in the gap as you get further from the blade on the IF table. Will grab some feeler gauges this weekend and take a measurement.
Also, thanks for the tip from the Delta. I'll check mine to see if there is an adjustment there. When I read the manual (gasp) it only mentions an adjustment to take up any slack with the gibs. There isn't any movement of the table, so that adjustment won't fix it.
Will repost after I've taken the measureent and checked for the "delta" adjustment.
Thanks for the help
DJS"Honey, will you please make some sawdust and track it across the carpet?"
"Yes, dear..."
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