Grease/lube for a gyroscope?

[sumptimwong]

Hey everyone. I recently built a gyroscope in the school machine shop, and will be competing in a timed event next week. I'm looking for a lubricant to go between the spindle and the bearing, but I'm not sure which lube will work best for my purposes. I thought to myself, "what better place to ask, than at BITOG?"

The spindle is made of Cold-Rolled steel, and is about 2mm in diameter where it slides into the bearings. The bearings are retrofitted brass screws, which had a small hole drilled into them to accept the steel spindle.

Currently I'm using Tri-Flow lubricant, which I've had moderate success with. My gyroscope is staying upright for about 3.5 minutes. Hoping to get some feedback from you kind folks about other possible lubricants. I'll also be trying out white lithium grease and some Havoline I've got lying around.

Thanks in advance!

 

[tom slick]

what type of bearings are you using?

 

[bruce381]

low touque use a oil only NO grease or a grease thinned with oil to a soupy blend would be best. Also try to "wear"
in the bearing maybe run it with a drill to supper polish the bearing.
bruce

 

[Kestas]

Bruce has a good idea. For break-in, try running the gyroscope with a fine abrasive compound used for metal polish instead of lube. This will mate the surfaces. Once the high spots are gone and the surfaces are burnished, use a light oil for lubrication.

 

[another Todd]

How about Remlube gun oil or sewing machine oil. I agree, do not use grease.

 

[rt_ponder]

How about spray on moly, saw this awhile ago, "swepco moly dry lube #812"
Sprayes on wet, dries in seconds, leaves behind smooth dry film of moly powder.
Ithink some parts stores in los angelas carries it,pelican parts I believe.

 

[Kestas]

Moly is more for EP, high temperature, or anaerobic applications to prevent cold welding. I wouldn't recommend it for low friction applications.

 

[rt_ponder]

I believe, that even though moly is an ep add. Beceause of the tight tolerances of a gyroscope, that the moly powder would reduce more friction than an oil would. A technical fine moly powder has 500,000 slippage planes, making it one of the most "slippery" friction reducers around, that's what the chemist told me.

 

[Kestas]

I've studied crystallography. 500,000 slippage planes is a stretch of the imagination in any inorganic material. The only useful slippage plane in moly disulfide is between the molybdenum and sulfur layers, owing to the weak bonding at that plane. The other planes offer high resistance to movement, i.e., high friction.

Oil, on the other hand has an infinite number of "slippage planes" and is more slippery in lightly loaded applications.

 

[Kestas]

Sumptim, it occurred to me that you may have problems keeping the oil in place while the gyroscope is spinning. The contact points may squeeze the lubricant out and run dry during prolonged spinning. You may try using a finish at the contact areas where the honing marks are patterned in such a way as to "pump" the oil back to where it's needed. I learned this trick from the seal engineers where I work.

 

[rt_ponder]

GEEZ KESTAS do you make a living proving people wrong too, or others opinion invalid? Don't have your credentials, but I've seen this product work on many occasions.

 

[Shannow]

sumptimwong,
If I had to guess, I'd say Malokule's Purple Problem Solver gun solvent/lube.

Reason being is that I had a holden wheel bearing (tapered roller) sitting in the lounge room, that my daughter (3) and I used to play with spinning it, and examining how it worked as a planetary gear set (don't ask...I think I've an autism spectrum somewhere).

I got some PPS for my other applications, and tried a drop on the tapered roller bearing. It lost the ability to be a planetary gear set, and a fast spin would result in pure skidding. There wasn't enough friction to spool up the rollers.

Tried it on a simple store bought gyro, and could unclip the sprung ends (causing an axial load on the spindle), and it would still spin for a long time.

 

[1sttruck]

Try whatever fishing reel oil is popular for a light duty / low friction lubricant. Quantum Hot Sauce Reel Oil use to get decent press.