Top Y rail worn

[Kyle Stapleton]

My top y rail has signs of wear and I was wondering if I could do something about other then buy new ones.

Will post picture tomorrow.

Thanks,

[srwtlc]

Kyle,

Drop the Y motor from the rack and give the Y car a push back and forth across the whole gantry and see if it's tight at any point. I remember adjusting it when we set it up, but it could be possible that something may have changed. Mine was a bit tight and while running a long 3D file that rastered in the Y, my top rail was dry and started galling slightly. While it did leave a slight bump in the rail, it hasn't bothered after readjusting the lower rollers and an occasional wiping of light oil to clean the rails and lube them. Newer PRS's have rail wipers/oilers and it would be a good idea to put some on it. You could purchase some from SB (ask about fit for an older PRS) or you can get the thick felt from McMaster Carr and figure out a way to mount them. Once saturated with oil, they'll keep the rails/rollers clean and lubed.

Since they're a hardened rail, I don't know if there's any good way of dressing them. I'd be willing to bet that your job of those many holes was the culprit. I'd try cleaning them off good with a scotch brite pad with some light machine oil or a penetrating oil on it and then a light oiling to finish. Recheck the lower roller adjustment and adjust as needed according to the manual.

If you find that it is consistently tight/loose on one side and not the other (depending on which side you made the adjustment on), check those rails for parallel. Mine were off a lot when I got the it and it took a fair amount of work/time to get them true. The newer PRS tools don't have the same rail set up as yours and mine and thus don't have that problem.

[Kyle Stapleton]

Here is a bad picture, I added a line to show the ware point.
This small line or bur goes from end to end as far as the Z travels and is on the front and back of the rail and seems to be made by the wheels.
I will be doing all the Scott has said to do as well.

[Brady Watson]

It's a fine line between those lower V-rollers being too tight & too loose. Back them off and slide the YZ car to one side. Then buff the entire rail with a brown scotch pad. Check the bottom rail as well. Buff smooth as needed. For more stubborn gouges - you may have to wet sand with soapy water or WD40 and 400-600 grit. Just work at it. They'll come up.

Work the v-rollers back up into the bottom rail. Move the YZ car back & forth by hand (you'll have to pull the Y motor to do this) and adjust them to where there is only slight drag on it. You'll need the funky flat wrench SB included + 14mm socket - depending on what YZ car you have. Adjust & check drag every step of the way.

Keep in mind it's steel. It's plenty workable even though it is case hardened. Worst case is, you order a set of top & bottom rails for it and replace them. And just a word to the wise...don't be stupid and lazy by using ANY power tool to dress the rails. You ain't that good & it only takes one little slip to destroy them. This is a strictly 'sneak up on it' by hand with finesse operation.

-B

[Kyle Stapleton]

Thanks for the in put, looks like I have a fun weekend coming up.:D

[Kyle Stapleton]

http://youtu.be/Srv4kRnWbkw

Hoping the y rail was the problem I did not mention the noise but after dropping the y motor and running a file I still have a noise.
please help.

[Brady Watson]

Dude...seriously? :rolleyes:

The very 1st thing I see in that video is mashed up chips poking out of the gear rack. Rake out the chips for crying out loud & clean the Y pinion...using a brass or stainless brush. THEN lubricate with grease and properly rock the Y motor up and into the teeth in the rack before tightening.

Chips have dimension & chips mashed into the rack will create noise, and positional loss. Now's a great time for everyone reading this to clean your machines.

-B

[srwtlc]

At about 10 seconds in, it sounds like the pinion is grinding/stripping on the rack, as if the teeth were barely engaged. Is the motor pushed up snug against the rack before tightening it down? How about the condition of the pinions? Worn pinions will be noisier. Run that motor with it disengaged from the rack. What do you hear then?

[Kyle Stapleton]

Checked all rack and pinion they all look new.

Dropped both the X motors and ran the same file from the video and no noise but I could feel the noise in both x motors at the same time.:confused:

Only makes the noise when I run file but sounds great using the key pad the move or jog.