Post By Screwmachine
lubrication for the bearings of spindle
I have a spindle for grinding machine with 20.000 rpm and I want to change the bearings of it. I took them from the trade , 4 pieces new, the number 7005CTYNDULP4, the same number with the spindle. I found out two symbols the "O" and the "V". My question is, how I will placed them? And second, when I received them ,I noticed that , they have a layer of oil for the conservation of them. Before I will placed them to the spindle, I want to put grease. Before I will put grease, could you tell us, if I must clean the layer of oil or not? And if yes, with which material I will cleaned them?
I'm guessing you have pairs at either end of the spindle; the configuration depends on how the spindle maker envisioned things. Do you have any tech info on the spindle?
As for lubrication- 20K rpm will test your cleanliness and technique pretty quick. You should clean the oil off in benzine, rinse in clean benzine, and be sure not to spin the bearing once it's oil free.
Then get some Kluber LDS 18 Special A grease (recommended by Schaublin for their lathes with angular contact bearings as well as Gepy for their small precision spindles). Mix it with benzine, 70% benzine to 30% Kluber. Soak the bearings in this, swish them around, let the benzine evaporate, and you are good to go. Too much grease is not good at all. Schaublin considers this adequate for 5 years of use. In a 20K spindle you might want to service it more frequently.
Most important is absolute cleanliness; and if the spindle requires some sort of manually set preload make sure you know the procedure and get it right. Those bearings have a preload ground into them already, meaning if they are stacked against each other or separated by spacers of exactly the same length on the inner and outer races there will already be preload. Lots to think about with precision bearings. And easy to toast a lot of money with one false move .
I really like this technique! It seems like a very good way to introduce the proper amount of grease into the bearings. Never would have thought of it. Mainly because I would be unsure of maintaining the grease's integrity after it being diluted.
Originally Posted by Screwmachine
Also is kerosene equal to benzine? Or what is benzine? We don't seem to use that word.
For the last rinse, I use full strength industrial isopropyl alcohol. It completely dries the bearing. I always feel if there is any oil type liquid on a bearing it's a dust catcher. Just my phobia. Of course I only do this right before installation.
I would appreciate any further comments Screwmachine, especially about the grease changing its original attributes. Thank you.
Also if anyone else has information about this, please post. This is important stuff! Really important Stuff!
Stanley- What we call benzine is "Petroleum ether" or "hydrotreated light naphtha". Very different from its homophone benzene. I don't know what the difference between 'light naphtha' and lighter fluid is. Maybe the same? The benzine I buy here doesn't smell like lighter fluid though.
A friend of mine in the U.S. just did this treatment on a set of spindle bearings and the Kluber people told him a readily available equivalent to benzine, will ask him what it was (hexane maybe). It's become difficult there to get certain chemicals- while here you just go to the drugstore and they'll sell you just about whatever crazy stuff you ask for. If they don't have it they'll order it in .
As it's a Kluber-approved process I take it that the integrity of the grease remains uncompromised.
Benzine is analogue to Benzin which is the German word for gasoline AND lighter fluid/ Mineral Spirits.
Not to be confused with benzene, being the basic aromatic hydrocarbon and a content of gasoline but absolutely not wanted (toxic) in mineral spirits.
That is an interesting thing. The benzine that is. I have heard of benzine for a long time, yet have never seen it, that I know of. I have heard that it is similar to gasoline and to mineral spirits.
Originally Posted by Zonko
It's a tricky substance to pin down. I'm in the watchmaking world, but despite it being mentioned in numerous texts on the subject, back in the mid 90s when I entered the trade it was already a forbidden fruit in the U.S.
Originally Posted by jdj
Here it's common and easy to get... BUT, not all Benzines are created equal. We used to get it in 20 liter drums, labeled "benzine legere 65/90". Legere means 'light'. It was great stuff. Then I moved and set up on my own, and went to one of the two drugstores in my new little town and asked for benzine legere. The guy gave me benzine rectifie (rectified), said it was identical. It wasn't. Left a film on parts, where the legere left none. Tried the other drugstore, got benzine legere, asked about "rectifie" and was told it was the same stuff, just different name- but this stuff was good. Then bought a liter of "legere" in a neighboring town and it was the same as the crappy "rectifie" .
Looking at this chart from Total, they list the 65/90 essence (essence is French for Benzine, though here they just say Benzine and as Zonko said interchanges with gasoline and mineral spirits in English ). But the 65/90 has the same CAS number as Isohexane, Heptane, Essence A and Essence C. Oh lordy..
For the record, the Schaublin tech manual specifies benzine rectifie- rectified benzine.
Great technique but now I'm completely confused. I thought gasoline = petrol and neither of those things is anything like the mineral spirits we buy to thin paint. The only benzene here is the toxic one you want nothing to do with. I think if you so much as remove the cap from a bottle of benzene outside of a fume hood you've exceeded the recommended exposure. The basic things available at the paint store here are mineral spirits, xylene, toluene, lacquer thinner, mek and denatured alcohol. Spot remover for clothes is, I think, perchlorethane, if it's still available. Of course there's also K-1 kerosene at the filling station and pure paraffin wax oil for lamps (no odor).
Wikipedia redirects you from Benzine, to Petroleum Ether. It puts it between Naphtha and Kerosene Petroleum ether - Wikipedia, the free encyclopedia It has a list of other names for it, including VM&P Naphtha. Which does seem to be readily available in the US. VM&P Naphtha - Rockler Woodworking Tools VM&P Naphtha Solvent, 1 Gal # 404101 by Sterling Clark Lurton