Cleaning of Ballscrews

[zoeper]

Hi All,

Refurbishing my machine and the ballscrews seems to have a ton of muck in them. Is it wise to disassemble them and if so, what is the procedure?
If not, what is the best way of cleaning them?
one is 1" diam and the other a 1 1/2"

Thanx
Pieter

[mxtras]

There are two basic methods:

1) the quick method - attempt to flush out the nut with a solvent/oil - something like WD-40, mineral spirits or kerosene. Soak the entrance of the nut and then run the nut over the screw, repeat many, many times. There may be wipers on the ends of the nuts - if they can be removed or at least loosened up, this would help with this purging procedure. WHen you are done, the nut will need to be lubricated properly. Do not attempt to clean out the nut by pumping rediculous amounts of grease into the nut and make sure you look into the correct type of grease to use - don't just use whatever you have. Get the right stuff and don't over-do it.

2) the correct method - take the nut off and clean everything really well and then re-assemble - it's not all that hard - you just have to be careful not to loose any of the balls. The disassembly/re-assembly procedures depend on what kind of nut you have. Posting a pic might help generate more replies to this thread as that would clarify what style of ball nut you are working with.

Scott

[zoeper]

Thanx Scot
My enthusiasm got the better of me and i just went and removed the nut by taking all of the balls out. Method 1 would never have worked in a million years as it seems like this machine was passing swarf through the nut faster than the swarf conveyor could get rid of it (maybe i mistook the swarf conveyor for a ballnut??)
I will post some pics later.

How do they pre tension a ball nut?

Pieter

[zoeper]

What fun it is to reassemble a ballnut!
I cleaned the whole lot today and reasembled. It took me an hour or more to get the first of the four sets of balls back. That was with trying to put them back through the hole that the recirculating tube goes into.
This is how i did the others. (the better way)

1. Stand the screw on one end and slide the nut body over it.
2. Insert the top recirculating tube all the way.
3. Count out the balls that need to go into that segment together and in groups of ten. (this way you load them 10 at a time and if any goes to the floor you will know how many to look for)
4. Put the firs 10 balls in by rolling them into the nut from the top end. (They will stop unce they get to the recirculating tube.)Roll the nut around the screw in an upward direction untill all 10 balls line up against the recirculating tube end.
5. Gently lift out only the top end of the recirculating tube until the balls start to pass. Continue rolling the screw so that all the balls pass the tube.
6. Repeat with the next group of 10 balls untill all balls are in.
7. Roll nut up and down by rotating the screw and watch for the spacing between balls. On my screw the gap was never bigger than a ball diameter proving that all balls are in circulation.

When doing the second set of the same half, make sure no balls are trapped in the dead zone between the two tubes. If there is a gap between two balls and it is bigger than one diameter, this might be the case.

When doing the x axis screw I will try and photo document "how to clean a ballscrew"
If anyone have some tips or other information that could be usefull, please post in this thread and i will combine it all into one document.

Pieter
PS this is the "before" of my z axis screw!

[mxtras]

Nice work! If you can find the time to do a write-up that would be extremely helpful to many, I am sure.

Scott