identify this spindle

[draemr]

Hi,

I'm building a new diy mill and got a spindle off of ebay. looks and feels nice, but don't know who made it. And especially how to keep it lubricated properly.

It's 2.75" in diameter, about 7-1/2" long in the body and has a spindle nose with a .750 bore.

There are two 3/16" holes in the end of the housing. one each end. the look like they go to the bearing journals either for cooling or lubrication or air purge.

numbers on it are: 49333-9 and 275-9644.

Guy I bought it from said it was from a disc drive manf. facility. It looks like it is a cartridge type grinding spindle, belt drive.

So, I'm looking to find out the mfg, and how to lubricate it when I'm using it.

See the pix.

Thanks for your help in advance.

Michael

[mc-motorsports]

That does look a lot like a grinding spindle, or some other sort of low load high RPM spindle. The best way to rate the one your going to rebuild would be to not exceed the RPM rating for the bearings you will install. I would think 10K would be just fine and should suit your needs.

I wouldn't put too much load on a spindle like that, they generally were never made for high torque milling ect. The shafts are thinner, the bearing placement isn't optimal and the bearings are probably ridgid and not meant for axial thrust loads.

As far as lubrication, most grinders are either greased and "sealed for life" to where the bearing was greased on assembly and no further lubrication is required for the life of the bearings. The other is an oil/air lubrication which those lube units can be expensive, but they basically just put a low PSI flow of air into the bearings with a slight mist of oil, too much oil and the spindle can get hot and the oil will tend to puddle inside. Not enough and you can guess what happens. You could just use an air tool air dryer and oiler, should work for your app, just use .125" nylon tubing to feed the bearing supply and try to figure a way to regulate the oil flow. Too much oil is better than not enough! And 20 psi is sufficient.

Hope this helps,
Michael

[draemr]

Hey, thanks so much Michael.

I think I will try to see if I can get the rough one apart to look at the bearings, possibly grease them in place if needed. That way I will know what bearings are in it so if I need to source them I have some numbers.

Is this spindle likely to be hard to get apart? or is removing the old bearings from the shaft the hard part?

Anyway, your comments helped me a lot. I'm probably going to use it for light duty machining at slow IPM using smaller diameter cutters, like maybe 3/8" max. So maybe I won't overstress the spindle bearings doing that.

Michael

[mc-motorsports]

Shouldn't be difficult to get the spindle apart, the bearings are most likely press fitted and will have to be pressed off. NEVER press on the outside race of the bearing unless you absoluty have to, this will 99% of the time damage the bearing. You may have to make a couple of tools and or fixures to properly dis-assembe the spindle, the new bearings can be installed by heating the inner race with a heat gun. Heat them until it's painful to so much as tap them with your finger. After so many years of experience, I just use touch. I think SKF reccomends 180*F if you care to use a temper stick. If your anywhere around NE Ohio, let me know. Good luck!
MC

[draemr]

Hi, just an update on the spindle.

I found some other spindle images on the net and I think these may be OMLAT-TORINO spindles.

I made a wrench to loosen the nut at the drive shaft end of the spindle, and I was able to get that to free up with out too much pressure. I marked the position of the nut so I could replace it in the same position.

After that, I loosened up the 6 cap screws around the spindle nose and after those were out, the spindle shaft came out without any trouble.

There are 4 bearings. The two nose bearings I measured as 2.165 in diameter, but that probably means they were 55mm bearings. They seemed thicker than I expected. The two front bearings were separated by a spacer and on the shaft was a preload nut that tightens them together at the inner race. I didn't touch that. I'm guessing these are AC bearings? Didn't see any numbers on them.

The two rear bearings are smaller, I measured 1.850 which probably means 47mm bearings. They also have a separate preload nut.

On both sets of bearings is a reddish/pink creamy colored grease, some of which has escaped the races. I'm wondering if I would need to get some more grease to add some, and what kind would it be?

That's as far as I went. I'm satisfied that it will probably withstand some load for the light milling I'm going to be doing.

I put it all back together which was uneventful.

Any comments?

Michael

[mc-motorsports]

Yes, more than likely angular contact bearings. As long as you didn't loosen the nuts that are locking them down, you should be ok. As long as you didn't disrupt the grease, I would leave it.

If you would like, you can look for L45 high speed bearing grease, it's a "barium soap" base as I remember, what ever that is... it's amazing how little grease the bearings need, and yes, after greasing them, most of it does tend to come out. My boss used to say "the bearing throws out what it doesn't need and will pull back what it does". Makes no sense, right? I never knew what he meant by that anyway.

Mount it up and try it. Plus, if it blows, a simple bearing arraingment such as that is easy to rebuild. You will just have to find bearings with the same ID, OD and thickness and choose the angle, preload and RPM rating that suits your need. Google a company called Bearings Inc. They have pretty much everything as I remember, not the best prices, but they will sell you 1 bearing if that's all you need.