Tablesaw Lubricating Advice

Tips on lubricating a sticky mechanism for raising and lowering the blade on a cabinet shop table saw. April 18, 2010

Question
The blade on my Powermatic 66 is awfully hard to raise. I've tried lots of different lubes on the gears over the years, but nothing works very well. Any ideas?

Forum Responses
(Solid Wood Machining Forum)
From contributor R:
It's probably not the gear; try lubing the pivot. The gear's lube is good for awhile but wears off. If relubing the gear isn't fixing it, then it has to be the pivot that is dry. The pivot may be a yoke which means there are two areas that need to be lubed.



From contributor M:
Also use spray lube on any bushings where the raise/lower and tilt mechanism shafts go through.


From contributor D:
I'm going to wager a guess that it's in the design. We have one here and I've seen a few older Powermatics that all suffered from the same problem. Spraying Liquid Wrench helps, but it may be inherently difficult to lift the heavy left tilt arbor mechanism with the worm drive geared too high.


From contributor S:
I agree that the problem is not the gears but in the bronze bushings on the pivots and the shaft of the crank handle. Oil is drawn into tight areas via capillary action. If the machine is of high quality, there is no space for any oil between the shaft and bushing, and oiling it will only provide short-term benefit.

I've also seen fine sawdust packed tightly between a shaft and a bushing. Bronze bushings should not be lubricated, and should not need to be lubricated. I suspect you need to disassemble the mechanism and clean the bushings and shafts. If any bushings show signs of slop or wear, replace them.



From contributor M:
There are no bronze bushings on a PM66, according to the parts diagram for a 1995 model. The steel shafts go through holes bored in cast iron assemblies.

If you grease and lube all areas where there are moving parts on the raise/lower and tilt mechanism, especially the shafts, it should solve your problem (it always does for me). Do not disassemble anything without trying this first. I usually get 6-12 months out of a lube job, but this depends upon usage.

I just did a full lube job on mine this morning and it took about 15 minutes. You will have to remove the motor cover to access all the areas that need attention. Some are easier to reach if you tilt the arbor, and a flashlight is invaluable. Move the blade up and down and side to side several times to distribute the lubricant throughout the contact areas, and you should be back to new in no time.



From the original questioner:
What kind of grease did you use?


From contributor M:
I use white lithium from a tube, which makes applying it easy, but I really don’t think the type of grease is very important. We're not talking about high heat or heavy usage on table saw trunnion and gear assemblies. If I didn’t have the white lithium I would just use the grease from my edgebander or automotive grease, but applying it would be a little more difficult. The spray lubricant that I use on the shafts is Boeshield T-9, but again, I think that any good quality spray lubricant would work just as well.


From the original questioner:
Thought I'd share something pretty off the wall. I poked around under the saw with a flashlight and realized the gears were really gummed up with crud. I found a can of 3M Citrus cleaner, sprayed the heck out of the gears, ran the arbor up and down, sprayed some more. So far, it seems to be working quite well with no lube at all. Now every time I fire up the dust collector, it smells like oranges in the shop.


The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
I have maintained a shop full of Powermatic equipment for 32 years and have learned this: steel shafts in cast iron holes wear the cast iron away into a very abrasive powder that eats the mating parts at an ever increasing rate. The best solution I know of is to remove the shafts, flush and scrub the holes with solvent, dry and grease with the thickest type you can find. My can of auto distributor cam grease is just about gone and I am having trouble finding more.



Comment from contributor J:
My aged Powermatic 66 also had a very hard time raising and lowering the blade and it was almost impossible to tilt the blade without very heavy effort.

Close inspection confirmed what I suspected: a serious buildup of sap and resin on the worm and spur gears.

The goo had combined with sawdust over the years and just clogged the gears -- especially the tilting gears, which mostly just sit there collecting sawdust and are rarely exercised.

I had poked at the gears earlier with a small flat blade screwdriver and ice pick, but with little luck.

Determined to clean it for good, I fashioned a simple scraping tool from a piece of wire about like a heavy wire coat hanger. The idea was to pick a piece of wire about the size of the root of the gear -- around 1/8" thick. I bent a loop handle into one end and bent a 1/4" ell into the business end, creating a tool about 8" long. This allowed me to scrape the buildup out of each tooth on the spurs and run the tool in the worm gear as I turned the handle. I literally had to chip off the crud in big chunks.

I sprayed WD-40 onto the gears and the pivot shafts, then scraped again.

I came here looking for lube recommendations. Not sure what Powermatic recommends, but I figured a light penetrating lube like WD40 would seep into tight places to free up shaft binding in the bearings and also dissolve or at least loosen resin buildup on the teeth.

I resisted putting heavy grease in the teeth because it could not help but attract and capture sawdust, then compress the mixture into the teeth.

After the cleaning and light lube, my saw operates like new. It's an absolute pleasure to turn the elevation and tilt handles. The blade practically lowers itself. The flywheel effect of the heavy iron handles literally helps lower the blade.

Don't forget to remove the locking knobs in the middle of the handles and lube the threads and clean the conical tips.

For access to the tilting gears, after removing the locking knob, remove the cast iron blade-elevation handle on the front using a 1/8" Allen wrench. Now the whole tilting gear mechanism is accessible. Clean the gears as you turn the tilt handle. Be sure to scrap all the way through the teeth on the spur. There was a LOT of crud in them. It was like hardened epoxy.

Also, remove the sawdust access panel on the front, put a towel on the floor and lay down on it. This allows you to look up and reach the elevation gears. Removing the motor cover also lets more light in and allows more access so you can clean areas. There was an amazing amount of buildup all over the inside of the saw, including melted plastic from when I cut some acrylic sheet years ago.

My little gear scraper now hangs on a small magnetic hook on the front of the saw. I can employ it more often so I won't have the buildup happen in the first place.

Still not sure what the official gear lube is, but my saw is working great now.