PM60 Jointer Table Alignment

[Daniel Thom]

Long time lurker, first time poster. Let me begin by apologizing if there is a readily available answer, though I've definitely searched and cannot find one...anywhere.

I recently picked up a "vintage" PM60 jointer. In the spirit of getting things done, I've attempted to do what I felt was the minimum to get it back into reasonable running condition, which in my case included:

Cleaned the tables and checked each table for flatness across the length at three points and diagonally across both diagonals. I couldn't get a .0015 feeler under my straightedge anywhere.
Removed the cutter head (bearings were supposedly replaced somewhat recently and they do seem very smooth)
Removed each table
Inspected, cleaned and lubed the ways and gibs with a thin layer of white lithium grease
Reassembled
Replaced the 4 gib screws with identical new cone screws and lock nuts (one original screw was broken off and I had to carefully drill and remove, so figured I'd just replace them all due to suspect abuse)...


To "properly" adjust the tables, for each table, I:


Checked the gibs were properly in place, with the dimples aligned with the gib and lock screw holes.
Installed the lock handle and lifted the table end while tightening the handle good and snug.
Installed the gib screws and ran them in tight and then backed off about 1/6th a turn (one face on the hex wrench).
Shimmed the cutter head a small amount to bring it to within .003" difference from side-to-side with the infeed table (got it to about .0015")
Loosened the locks and moved the tables inline with one another based on the height of the 0 depth indicator on the infeed


After doing all of this, the jointer tables were much closer to coplaner than when I started, but there was still a sag at the end and a bit of a tilt back-to-front. I'll just say these are on the outfeed side, since that's the side I worked on to bring it inline with the infeed... So I shimmed the outfeed until it was just perfect and locked and left it alone. When I say perfect, I mean I couldn't slide the same .0015" feeler under my straight edge anywhere. I could barely see light under the straight edge anywhere either.

Here's the major problem... As soon as I lowered the infeed side, the front edge near the cutter lowered before the back edge a significant amount (at least .008", maybe more). No more coplaner. I could bring it up and down and this repeated each time. Locking made no difference... Tightening the gib screws until it was nearly unreasonable to move the table made no difference...

I remembered the table moving more "normally" before I had set the gib screws appropriately snug, so I went back through the procedure on the infeed side only, this time only setting the gib screws to not really snug instead of pretty snug. (so technical!)... The table no longer drops away on the front edge first! HOWEVER, as soon as I lock the table, the alignment changes. My thinking is "who needs a lock anyhow?" I could also just adjust the darned thing at 1/32" cutting depth and never move it.

Any opinions?

[Andrew Hughes]

First congratulations on finding a jointer with dead flat tables. .0015 is a very small number I think you might be meaning one thousand and a half. Because .0015 is tenth of a thousand If I remember correctly.
Anyways your alignment issues seem to be with the Dt ways maybe something fell in there and is goofing up the fit? Also would keep the ways dry maybe a little wax you don’t want them collecting dust. Eventually that could come back to bite you.
Right now there’s lots of vintage pm jointers on cL glad to hear someone has one.
Good luck

[Daniel Thom]

Thanks! .0015 is one and a half thousandths. Or I suppose you could say fifteen ten thousandths as well. ;-)

As for the lube, yes, I know some run them dry. I just decided to go with a small amount of lube, per the original Powermatic manual, though I choose lithium grease as it's the best I had for this purpose.

I don't think I have any foreign item in the ways, but I do agree it seems like something with the ways. Like when they are pushed fully into place by the gib, something is not lining up the same. I maybe should pull the infeed table again and check things more closely, but I'm not sure past a visual inspection what to look for. Better option than just never locking the infeed table?

[Andrew Hughes]

I knew it was small number 15 thousand sounds smaller the one and half.:)
Anyways you know what happens with these old machines they get lifted from the ends of the tables. Maybe nothing you can do about it. Sure seems like its worth inspecting the ways a little closer since the tables are a fine as it gets.
I don’t know if would be satisfied using a jointer with a fixed indeed.
Maybe have to play the hand your dealt and see how you do?
Let us know what you find.
Good luck

[Daniel Thom]

Andrew,

Thanks and no worries about the measuring! Ask me how to do something with fractions and I fall apart... I can't tell you how many times I've cut something 1/8" under instead of over... I like to measure twice and cut three times. :-)

I have to say, the ways *looked* ok before I reassembled, no obvious major wear, etc. But I didn't try to do any kind of measuring to verify the appearances. The fact that things seemed to be ok with the gib screws being just a bit looser makes me think I may be able to just use it like that (presuming it really does adjust properly, I have to readjust then measure for any change)... I don't know that locking the table is really necessary. I can't imagine it spontaneously moving, but then again, I have no experience with this machine.

I also wonder, in the back of my mind, if someone were to have mixed up the two gibs in the past before I got it (I know I didn't because I serviced one side at a time)... I think they surface the two tables together with gibs installed at the factory, thus making the gibs specific to the table... But a gib causing this problem seems a stretch for my brain unless it has a lump in it... I'm just debating how insane I want to drive myself with this machine vs just limping it along for now so I don't have to keep working around not having a jointer!

-Daniel

[Andrew Hughes]

Maybe I’m wrong but it don’t think the gib screws are there to adjust the table alignment. They should be tight but not so tight that you cannot move the table with the hand wheels. I haven’t seen every year of pm jointers so anyone wants to correct me that’s fine.
The ways should fit together unless they are cracked or broken. The the gib screws hole them there. Make sense?

[Daniel Thom]

You're correct, the gib screws aren't for alignment, though they do *massively* move the alignment by forcing the gib into the way and thus "aligning" them. My understanding is that, on a jointer, they should be relatively snug as the tables aren't adjusted with much frequency (unlike a machinists mill or something where there is always travel as a function of the machine)... The last little bit of adjustment on the gib screws can make a fairly large difference to overall alignment though, which is why they need to be locked down as they definitely make a difference and can throw you way out. It's that last little bit I'm fighting with as if I make them snug enough that the lock doesn't change the table alignment, then the table comes out of coplanarity (is that even a word???) when it is moved. If I make them a little less snug, the table appears to stay coplanar (I need to actually measure, but it's for sure *WAY* better), but the lock moves the table out of coplanarity... So I'd rather give up the locking of the table, which seems mostly pointless and if I'm proven wrong, I could probably devise a way to lock the table with the actual adjustment handle...

But it seems like I can't be the only one to ever struggle with such a problem? I don't think I'm doing anything wrong with my adjustments. I'm pretty sure I've got them well within the ballpark. Yet...

[Andrew Hughes]

I see what your taking about that lever handle. I don’t ever remember using it on my In feed side only the outfeed table. Never felt like the tables would move without me involved. It’s been about six or seven years since I had a Dt way jointer in my shop.
Your on the right track.
Good luck

[Daniel Thom]

Thanks Andrew! I'll give it a shot without using the lock handle, may be a day or so before I get back out there, but I'm super excited to get to making scrap wood and sawdust!

[Andrew Hughes]

Sounds cool 😎 sorry for implying you were trying to adjust the tables with the gib screws. Let me know if you have any trouble get flat straight edges. I’ll try to help and pay attention to what’s going on.:)

[Daniel Thom]

No worries at all! I really appreciate the replies and questions, it never hurts to clarify! I'll post back after I spend more time with it in the next day or two for sure!

[Chris Hachet]

Congrats and good luck. I also have a vintage PM 60 that I pretty much leave for a strong 32 of an inch cut.

[Daniel Thom]

So I readjusted/shimmed the tables without locking the center table lock handle on the infeed side and with the infeed gib screws set a little less tightly. The table now maintains much better coplanarity when moving, though I'd say it's not perfect, so I may fiddle more, but for now, I put in freshly sharpened knives and ran a few short test pieces through and had perfect results on those test pieces. I'll need to run a couple longer pieces through to test the jointing fit for ultimate perfection still, but I'm confident that will be good given what I've seen so far and if not, I'll readjust for 1 1/32" cut and leave it there. I'll probably replace the center locking handle with another larger gib screw and lock nut so it is helpful for keeping alignment instead of just a lock I'm afraid to use.