[bohica]

I have scoured this forum and have found nothing regarding lubrication of the ball screws. In my ignorance, I installed a one shot lubrication system using grease to both ways and ball screws. When I spoke to Gene of IH, he told me that grease on the ball screws would be a great big no-no, and suggested using 10wt hydraulic fluid.

Has anyone developed a method of lubricating the x, y and z axis ball screws? I am thinking of a oil/air misting system for all three axis, but feel that I should look at existing solutions before I have to reinvent the wheel. I've done enough of that over the years.

Considering that this seems to be an very inventive group, someone may have arrived at an elegant solution for ball screw lubrication.

[Geof]

I have a Haas Toolroom lathe and a Haas Gantry Router. In both cases the ball screw lubrication, and linear ways, is by general purpose grease. I find it difficult to understand how it could be considered a no no. One reason for using grease when the lubrication is intermittent, as in once month for the router, is because it is designed to not drain out of whatever it is lubricating. Oil, proper oil with extreme pressure additives and additives to make it sticky, in other words Way Oil, is suitable if the lubrication is constant.

[bohica]

Gene told me that grease is to "sticky" and would prevent the recirculation of the balls in the ball nut and would lead to excessive wear on the ball screw.

[Cruiser]

The grease will hold chips and grit ! for a long time. I use vactra #2 oil. I did use some molly lube for slicking the slides but went right into oil after that.

[Geof]

Gene told me that grease is to "sticky" and would prevent the recirculation of the balls in the ball nut and would lead to excessive wear on the ball screw.

Well grease is used extensively for lubricating ball races and doesn't stop the balls circulating. A ball screw/nut is not all that different to a ball race.

My feeling is that the engineers at Haas probably know what they are talking about. Have you looked up recommendations from the ball screw manufacturers?

[bohica]

I just did a google search for "ball nut lubrication". The results seem to show more favor towards oils as opposed to grease. See the following link.

http://www.lsitvc.com/lubrication.htm

Cruiser, you indicated you favored oils. How do you deliver the oil to the ball screws/ball nuts?

[fatboy55]

Hello everyone, I don't have ball screws, just the standard acme but I use moble synth oil 5w30 weight. What do you all think about that for the ways and screws?

Jeff

[bohica]

Jeff, that lube is fine for a manual machine, you don't have the load on the acme screw. With CNC, the ball screws have a heavy load during operation.

[Cruiser]

Bohica, I use the old oil can and give it a squirt whenever i think of it. when running wet the coolant takes care of some of it. more important to the IH mills is the X slide and screw as they are covered by the table and don't get the coolant washdown. grease could have some benifits but since we don't have covers to keep the area clean it is going to be a magnet for everything and cause destruction, as the grease will carry grit and chips into the works ! Biggest benefit of the oil is it will flush off the grits, an oiling system for the X slideway from the underside straight into the slides with some flow channels would shure be nice as I see it.

[kentavv]

grease could have some benifits but since we don't have covers to keep the area clean it is going to be a magnet for everything

Got to agree with that. But, why did all the photos of the CNC conversion on IH have the way covers removed anyway? Sure, the travel is increased 1/2" or so but at the expense of gunk getting onto the ways, ballscrews, and into hard to clean places. I have since reattached mine.

FWIW: I squirt a lot way oil on to the ball screws.... it's a pretty messy operation

(A quart of bad oil is better than a quart of no oil)

[philbur]

As you have installed a one shot system why not just use it with oil instead of grease.

'Phil

I have scoured this forum and have found nothing regarding lubrication of the ball screws. In my ignorance, I installed a one shot lubrication system using grease to both ways and ball screws. When I spoke to Gene of IH, he told me that grease on the ball screws would be a great big no-no, and suggested using 10wt hydraulic fluid.

Has anyone developed a method of lubricating the x, y and z axis ball screws? I am thinking of a oil/air misting system for all three axis, but feel that I should look at existing solutions before I have to reinvent the wheel. I've done enough of that over the years.

Considering that this seems to be an very inventive group, someone may have arrived at an elegant solution for ball screw lubrication.

[bohica]

Wildcat, One of the big problems is the type of material you are machining. Aluminum is no problem, the coolant (if the way covers are left off) provides a continous flushing of the ball screws. Now cast iron is a completly different story. This material produces a lot of very fine swarf, which is probably an excellent abrasive and I don't think you want any of this in your ball nut.

I will be machining some stone (jasper, obsidion, petrified wood). This produces a lot of very fine silicon dioxide material and I definetly don't want that in the ball nuts. I left all of the way covers on for this very reason. and will be installing additional way protection as well.

Philbur, The pump (Centro-Matic) and the injectors are designed for grease (they have oil pumps and injectors), but I plan on trying it using oil. Not sure it will work properly. In any case, the Y axis lube method I used will not work with oil so I still have to make some modifications.

I appreciate all of you comments. I think this issue is something IH needs to address on their web site and offer some lube specs and plans.

I am going to tear it down and install a lubrication point in the X and Y axis ballscrew mount fittings. It's a PITA, but I would rather do it now than later wishing I had!

[NC Cams]

NSK makes high precision ball screws and linear ways. WHen I worked there, a very common GREASE lube that was used in/on them at the time was Shell Alvania #2 GREASE. For low friction, Exxon Beacon 325 was used but this tended to be a bit runny as compared to Alvania even though both greases supposedly had the same NLGI viscosity rating (#2).

Grease is nothing more than a lubricating oil with a thickening agent. The thickening agent could be an number of compounds who's sole purpose is to increase the grease viscosity and/or to make the stuff adhere to surfaces where it would otherwise run/slide out/off.

If you go the oil route, you're probably going to have to REGULARLY replenish it otherwise, it is going to drip/run off due to gravity. If you slather grease into the load zone, it should coat the parts and the lube should remain in place more effectively.

Oil tends to get/be messier simply because it leaks all over. Grease is no more or less prone to attract dirt than oil and, perhaps less because it stays put until/unless it gets hot and runs.

For high speed used, grease tends to be more viscous and it will create more heat problems. For low speed use, oil can more easily rupture the lube film (because it is less viscous). ANY situation that is associated with high frequency oscillatory motion is hard to lubricate properly regardless if you use grease or oil - we've had the best results with EP greases that have self plating zinc additives and/or moly disulphide additives in such applications.

[BrendaEM]

I read an article on rebuilding bike forks which someone reverse engineered RockShox RedRum, and found it to be Torco MPZ Engine Assembly Lube.

Given that engine assembly lube is supposed to stick to things, and take a lot of pressure, such as during engine main bearing break-in. Perhaps it would be good for milling machines too.

Sieg owners would freak out if you put a red colored lube on your machine, as their rite-of-passage is taking the original red grease off.

[Geof]

I read an article on rebuilding bike forks .....

I read your link and found this: "Mineral oil is a great alternative to DOT Brake fluid. Mineral oil is not caustic and is non-toxic, but the main performance advantage to the rider is that mineral oil will not absorb water from the air like DOT fluid will....

Which is an interesting piece of advice.

I have no idea what material the seals in bike hydraulic brakes systems are made from.

I do know that everything I have read about rebuilding brakes on cars and motorcycles cautions against getting mineral oil anywhere near the seals in hydraulic brake systems because the seals are not compatible with it.

[Pres]

.... that mineral oil will not absorb water from the air like DOT fluid will....

FWIW:
Close to true, except for DOT5 -a silicon based brake fluid.
Expensive to buy, but does not absorb any water.
(water just beads up in the bottom of the fluid)
The silicone coating stops ALL rust and corrosion.

DOT 3 & DOT 4 are the cheaper, water absorbing type.

Pres

[ckm]

FWIW:
Close to true, except for DOT5 -a silicon based brake fluid.
Expensive to buy, but does not absorb any water.
(water just beads up in the bottom of the fluid)
The silicone coating stops ALL rust and corrosion.

DOT 3 & DOT 4 are the cheaper, water absorbing type.

Pres

I just want to reply to this before someone uses a silicon based brake fluid. Just as background, I have been restoring cars (but not professionally) for 15 years and racing for 10. I have a full shop, 3000 sq. ft. of workspace with every kind of automotive tool you can imagine.

You should NEVER use silicon based brake fluid in a street car. NEVER. In fact, it is very, very dangerous to do so.

There is a very good reason why brake fluids absorb water, it's actually a design characteristic. If they didn't, water would pool at the low points in the system, then boil into steam as the system was used, creating a compressible gas, potentially making the system inoperative. Also, water pooled at low points can cause brake line to rust, as these are mild steel, corrosion coated only on the exterior.

There are three circumstances where it is acceptable to use silicon based fluid:

1. It is specifically required by the manufacturer (none currently to my knowledge)
   
2. Race-only car, the fluid is typically changed after each race.
   
3. Museum car, where it will sit for long periods. Note that the system MUST be flushed before the car is used.

One final note, you CANNOT go back to regular non-silicon fluid after using silicon-based. It's a one-way decision. If you want to go back, all the components must be changed (at the very least all the lines and calipers, the rest must be throughly flushed).

If you are really worried about moisture in your brake fluid, change it often. It's cheap and you should change it once a year anyway. High-performance fluids like Agip Blue actually have higher performance characteristics and boiling points than silicon-based, some most race teams just use hi-po regular fluids.

HTH,

Chris.



There

[SMW Precision]

Thought I would see what Ballscrew Manufacturer said on lubrication. This is their quote!

Lubrication Lubrication is required to achieve optimum life for a ball screw assembly. Ball screws that are not lubricated can experience up to a 90% reduction in calculated life. In general, standard lubrication practices for anti-friction rolling element bearings apply. Grease, oil or dry film lubrication can be used. Many ball nuts are equipped with a 1/8-27NPT lube port machined into the nut body. For models that do not have a factory lube port, contact factory for recommendations on lubrication application.

See page 15 for Rockford Ball Screw Grease. This lubricant is specially formulated for use with ball screws as well as ACME screws and bearing mount assemblies. Rockford Ball Screw Grease is packaged in convenient 14 oz. grease cartridges.

http://www.rockfordballscrew.com/