Jointer/Planer question: how far out before you make adjustments?

[Jeff Ranck]

So I've been in the process of setting up my new minimax FS30c Jointer/Planer. It has been slow going since I have had very little shop time due to work and other commitments. In any event, I've been checking all the alignment of things with a dial gauge starting with the jointer outfeed table alignment with the cutter head (the xilent spiral cut one). From one side to the other, the alignment is out 0.003" (higher on one side than the other). To adjust, you turn locking nuts, and move bolts in or out with a wrench. I've been wondering, can I really take out that much or am I going to simply mess things up further?

So how far out of alignment before you start making adjustments? I know it is to some extent personal preference, but at some level, you are limited by how accurate you can be as you tighten down the locking nuts after you adjust things. Things always seem to move around a bit.

[Jim Becker]

Run some wood through it before you do any changes to the setup. That's the bottom line. If you cannot perceive any real difference in the materail you're milling, don't worry about making the adjustment. Three thousandths is pretty small... ;) ...and wood moves more than that in a day.

[Bill Dufour]

0.001 is the number I have seen that makes a visible line when two boards are joined and finish is applied. of course most of us would sand it a bit even if it looked perfect after glueup.
Bill D.

[Prashun Patel]

I do as Jim says. If I can joint a flat enough face and square enough corner that I can't see daylight under the piece against a known, good straight edge or square then it's good enough for my joinery.

I set up my Hammer A3-31 and didn't even bother to align it before trying it out. It passed my eye test and I haven't felt the need to touch it in 2 years.

(The good thing about the eye test is as I get older, the tolerance of my eyes gets wider and wider, which works out well for my own perception of the quality of both my alignment and joinery.... ;))

[Van Huskey]

I am in the Jim/Prashun camp, adjust only AFTER I determine the results are not satisfactory. Keep in mind moving a 16 TPI bolt .003 is roughly 17 degrees of rotation. I have no idea about the actual thread pitch but it gives an example of how little the actual adjustment could be.

[Patrick Kane]

I adjust things until they are as perfect as i can attain. On a table saw that is .001" over a 10" blade fully raised. If its .002" I will MAYBE let it slide, but .003" i will take the time to improve it. As far as a jointer, i would not accept .003" over 12". Over 16" or 20", i probably would. More importantly, how does that compare to the tables' relation to one another? Are they coplanar? If they are .001-.002" coplanar, then I would deal with the cutterhead being out slightly. I say this, because you will inevitably throw off the relationship of the tables the second you go to adjust the high corner of the outfeed table. Did you check the planer table relationship to the cutterhead? That i really wouldnt accept anything more than .001" out over 12".

My used 20" jointer came to me completely out of whack--it was maybe 1/8" out of coplanar over 38". I spent 6-8 hours adjusting it three separate times to get it to where i was comfortable. I think the outfeed table is .001-.002" out of parallel over 20" to the cutterhead, and the beds are .001-.002" out of coplanar over my 38" straight edge. I really need a longer straight edge to improve on that. I think it is worth the time(my situation was extreme, mind you), because on properly built machines this is something you do once every 5 years. Unless i start jumping up and down on the end of my outfeed table, i shouldnt have to adjust the jointer again until i move it. I own machines to make my life easier and my end product better. That doesnt happen if i dont maintain and calibrate them to the highest of standards.

[David Kumm]

The planer table is more critical. How is that? Dave

[Jeff Ranck]

The planer table is more critical. How is that? Dave

Haven't gotten that far yet.

[Rod Sheridan]

I do as Jim says. If I can joint a flat enough face and square enough corner that I can't see daylight under the piece against a known, good straight edge or square then it's good enough for my joinery.

I set up my Hammer A3-31 and didn't even bother to align it before trying it out. It passed my eye test and I haven't felt the need to touch it in 2 years.

(The good thing about the eye test is as I get older, the tolerance of my eyes gets wider and wider, which works out well for my own perception of the quality of both my alignment and joinery.... ;))

Yup, that's what I do as well.

If the test cuts are satisfactory, the machine doesn't need any adjustment.................Regards, Rod.

[Bill McNiel]

(The good thing about the eye test is as I get older, the tolerance of my eyes gets wider and wider, which works out well for my own perception of the quality of both my alignment and joinery.... ;))

Thank you Prashan - I've been laid up for a couple of days and your post brought the first rays of humor into a bleak world. I truly laughed out loud.

[Art Mann]

I agree with Jim, Prashun and Rod. If you joint and plane material that is flat and straight as measured with a precision straight edge, don't mess with it. You can make it worse rather than better. When I bought my Jet JJP-12HH, I just plugged it in and started using it. It produces stock that is well within the margin of error which can be attributed to technique or material flaws. Just a few days ago, I got out my precision straight edge and measured the coplanarity of the infeed and outfeed tables. There is, in fact, about a 0.003" drop at the very front of the infeed table. I would have to be out of my mind to attempt to adjust that away. It just doesn't make any difference, especially if you use the correct jointer material handling technique.

I read with some interest the comment Patrick Kane made about correcting a 0.003" error in the alignment of a saw blade to the miter slot. I would like to see a demonstration that this activity produced any measurable change in the accuracy of width or straightness of a set of test samples. I would bet that there is more variance attributable to cutting technique than anything else. This is similar to an actual experiment I have done in the past measuring the accuracy of a crosscut sled.