Grease and the z rail

[shilala]

I've crawled all over my paperwork and the intersne to find some good direction on greasing my 2012 PRS BT48.
Excuse me as I explain what I grease, I'm ashamed I don't know proper names of parts, especially since I've been a mechanic all my life. :D

I grease the rails that the machine glides on, but very lightly. Just enough to see that they can't rust. I do that under the table and on the y axis. I do the best I can with the Z.

I grease the two gear tracks, x and y. I can't figure out how to get into the z without tearing the whole thing apart.
I feel a little "hitch" in the z axis when I glide it up and down (when it's not under power) and it makes me think there's a clinker stuck to the gear track.

Can someone please run down what needs greased and how to pull apart or access the z gear rail? It's pretty simple, but I'd far rather have a little heads up before I steamroll into it.

Thanks!!!

[dana_swift]

Scott- I may not be following the manual in this case, but I only grease the rack and pinion gears on all three axes. The rails are not greased to prevent chip collection. The chip particles on the rails would make "bumps" the rollers would have to climb over and ruin accuracy in the related axes.

The wipers on each side of the V rollers wipe the dust off (usually) and make a nice smooth track. If there is a small oxide layer, it would make less roughness than the chips collected on grease.

This will no doubt bring about a lively discussion-

D

[garyc]

Scott, Dana, et al....
This is NOT an official document, but is one I hand out to the Production Customers I visit for maintenance, tune-ups and training. If your actual use is less than the listed 40 or 20 hrs per week, then adjust your schedule accordingly.

[shilala]

I follow your line of thinking completely, Dana. I just set to cleaning that z gear rail. I tied a wire to the spring, dropped it, and I'm fishing around in there with a wire toothbrush.

Thanks for that schedule, Gary. That's the Holy Grail I've been searching for. Mind ya, I haven't opened it yet. I'm trying to degrease and go fetch the kid at the bus stop before she's rain-soaked. :D

[shilala]

I managed to clean all the grease off everything.
I used some solvent to clean the z gear and gear track, along with the solvent, wire brush, and xacto knife. It cleaned that lumpy hitch right up, Dana called that perfectly.

From here on out I'm just going to use a light lubricant to keep stuff from rusting. Maybe that Boeshield stuff. T-9 should work on the entire machine, ya think?

[rb99]

Scott, Dana, et al....
This is NOT an official document, but is one I hand out to the Production Customers I visit for maintenance, tune-ups and training. If your actual use is less than the listed 40 or 20 hrs per week, then adjust your schedule accordingly.

Is there any documentation or videos on the setup and maintenance of the Z's?

[Brady Watson]

Grease your gears. Keep them wet. Lightly oil your rails to keep them clean, bright and rust free. Later PRS should check your felts (under the black v-roller covers) and oil as necessary.

-B

[garyc]

Richard...
Not that I am aware of. During the course of the maintenance, which is usually done with the owner or operator, they are shown first hand how to clean the Z and how to dissassemble it once a year for a thorough clean and lube of the rack and roller bearings.

[jhedlund58]

This is maintenance schedule i was given last week from chris at shopbot... tells more of when than how... the MSWord file was too big to attach... so i pasted it below... u can cut and past into word to get better formatting

ShopBot Machine Maintenance Schedule:

Daily before cutting:
1.) Warm up spindle for 6-9 minutes with C5 routine or ½ RPM
2.) Warm up vacuum pump for 5 minutes with open air valve open. Check gauge for proper vacuum. Should read at least 13”Hg.
3.) Check spindle fan. Wait for the fan to come on before hitting blue reset button. Hold your hand above the fan to confirm air flow.
4.) Check bit, collet and collet nut for wear and debris. Collets are good for 400-500 hours of use if they are kept clean and no “event” occurs such as a broken bit inside the collet or a plunge that bottoms out on the collet.
5.) Check rack/pinion/motor/shaft relationship by rapidly pushing and pulling the carriages near each motor. X1, X2, Y and Z. Adjust motor mount and/or tighten set screws.
6.) Verify square gantry by pulling it against the stops at the end of the table prior to resetting motors. Hold in place and press reset.

Monthly:
1.) Clean rack and pinion with small brush and re-grease. Add a BB size blob every 12” and run the tool end to end about 20 times. Wipe off any access grease.
2.) Wipe all exposed metal parts with light machine oil.
3.) Add light machine oil to felt oilers inside of the 8 wheel covers and z-axis sweeps.
4.) Check rack/pinion/motor/shaft relationship by rapid push-pull. X1, X2, Y and Z. Adjust motor mount or tighten set screws.


Semi-Annual (40hr/week) to Annual (20hr/week):
1.) Replace pinion gears
2.) Check spindle square and alignment.
3.) Update software
4.) Update firmware
5.) Clean rack and pinion with small brush and re-grease. Add a BB size blob every 12” and run the tool end to end about 20 times and then wipe off any access.
6.) Wipe off all exposed metal parts with light machine oil.
7.) Add light machine oil to felt oilers inside of the 8 wheel covers.
8.) Check rack/pinion/motor/shaft relationship by rapid push-pull. X1, X2, Y and Z. Adjust motor mount or tighten set screws.

[rb99]

Richard...
Not that I am aware of. During the course of the maintenance, which is usually done with the owner or operator, they are shown first hand how to clean the Z and how to dissassemble it once a year for a thorough clean and lube of the rack and roller bearings.

I just bought an unused but used 12" retro Z and I am not sure about the maintenance you described in your maintenance sheet. Is there any info about the Z anywhere?

[garyc]

Richard...
I am not aware of any docs other than the recommendation to dissassemble, clean, adjust, lubricate and reassemble. Make sure that there is smooth motion thru the full range of movement.

Here, to the best of my recollection, are the steps I use for the PRS. There are slight variations between the 3 generations of PRS Z assemblies. Some of these items are performed with the gantry at the -X end of the table and others at the +X.

Power off to VFD/Router
Remove Dust collection and cables to spindle/router
Remove bits, leave collet & nut on spindle
Remove springs and hard stops (plates and/or bolts)
block under collet and remove Z stepper motor
Slide Z assembly up and out
Clean rack, scrub, clean polish utilitrack (or dual rail)
Remove, clean check v roller bearings for smooth rotation
Verify mounts are square with YZ car, parallel and clean
Reinstall bearings, lube & reinstall Z assembly
Adjust 10 bearings for smooth operation as per manual
Clean, oil & install wipers & blocks
Replace pinion, lube rack and reinstall Z motor
Connect wires and dust
Clean, scrub, adjust and lube Y bearings, rails & felts.

This is an expansion of the line: 2) Remove, clean, inspect, reassemble, lube and adjust complete Z extrusion assembly. in the Maintenance Shedule. Twice a year for 40 hrs a week use or once if used 20 or less. More often in high dust environments. Intermediate clean and lube can be done thru the Z motor opening.

There is more info in the manual, the latest version is avalable for download or view here: http://www.shopbotdocs.com/

[rb99]

Thanks Gary...

This line: "Adjust 10 bearings for smooth operation as per manual" I am not sure which bearings, and I clicked link and have gone through but I must have missed it. Could you tell me which manual you mean? Thank you.

[garyc]

Richard...
The ShopBot Assembly Manual..
"Widely Distributed, Seldom Read"

There should be an updated PRS version on the SHopBotDocs site that you can view or download.

[rb99]

Richard...
The ShopBot Assembly Manual..
"Widely Distributed, Seldom Read"

There should be an updated PRS version on the SHopBotDocs site that you can view or download.

I have gone over the PRS assembly doc a number of times... I cannot find the Z info.

[garyc]

Richard...
When in doubt use the great oracle in the cloud. (Google search) :D I searched "ShopBot Z axis adjust" and it returned: http://www.shopbottools.com/files/docs/SBG00342081230AdjustPRSZBearings.pdf

[rb99]

Nice! Thanks Gary!