PM1000 Table Saw

[Steve Nieuwsma]

My PM1000 table saw will not hold the blade height when using a dado stack. It does not appear to have blade height nor angle lock. The saw works fine on other blades (rip, cutoff etc.) and I assume it’s due to the heavier load when cutting a dado, especially on QSW oak. When I cut a dado it’s starts off fine and then starts the drifts too deep even when taking light cuts and feeding slowly.

[Aaron Inami]

I would imagine the blade height might crawl with normal blades as well, but it wouldn't matter if you were making a normal cut. I did not experience this on my old PM66 tablesaw. You might contact Powermatic support.

I think the small knob inside the handwheel can be tightened to help "lock" the blade height. That should help if it is the wheel/gear crawling up and not some other problem.

Maybe check the flatness of your table. If there is a dip or hill, it may affect the beginning/middle/end of the dado cut.

[Bill Dufour]

They look like they have lock knob in the middle of each control wheel. That is how a unisaw works at least. There is something down inside the hole that the lock knob shaft pushes out to lock things down. I believe the unisaw lock shaft is 5/8 fine thread with a 30 degee taper point at the deep end.
I see many unisaws for sale with missing lock knobs. Easy to make from all thread if you have. a lathe or even just a grinder. the taper is not critical.
I made one for my rockwell 12/14 with dimensions from Bruce Wren. Thanks Bruce.
Bill D

[Earl McLain]

On my TS (not a PM 1000), the lock knob compresses a fiber washer to secure the lock. Age, compression, dust, whatever renders the fiber washer less useful over time--and should be considered a wear item. Replaced mine with one from the Ace Hardware bins and solved a similar issue. As mentioned, it wasn't noticable on through cuts, but it'll mess up a dado!!

[Bill Dufour]

https://www.ereplacementparts.com/powermatic-pm1000-1791000k-10inch-cabinet-saw-parts-c-32549_32640_388350.html

[Dave VanDewerker]

There should be a large silver knob in the center of the height adjustment wheel to lock the height. Is this knob missing on your saw?