Oil zerk fitting for lathe turret.

After another expensive breakdown I decided to make a pathway for the operator to grease the rollers that a ring gear rotates on to drive the live tools.
Oddly there was no provision for grease or oil to the rollers, and eventually coolant turned the original grease into hardened mud, which not only caused the ring gear to seize but also rusted both the inner surface (Raceway) of the ring gear and the rollers and the inner raceway.

We ground the ID of the ring gear with a tool post grinder and sent the inner race to a hard chrome shop to grind past the rust, build up with chrome, and then grind to finish size. The rollers all went into a vibratory tumbler until the surface rust was gone.

I called the USA tech center for this machine and they knew of no method to grease or oil the roller raceway. Amazing!
So I drilled a long .089" diameter hole down from the outside of the turret base and ended up near the center of a 6MM flange that holds the rollers from walking out sideways, and then cross drilled a communication hole to the roller area.

I assumed the 115 rollers (6MM diameter X 8MM length) were lubed with grease so at the operator end of the longer hole I tapped it for a 1/8" grease zerk.
But when we assembled the whole thing with lubriplate it seemed like there was a lot of grease friction, which wasn't there when it was all dry inside.
So now we have a grease zerk that wants oil. Is it possible to inject oil through a zerk? If so, does it take a special injector oiler? Where can I get one?
Alternatively, is it possible to find a 1/8 NPT fitting with a female cone and ball that would work better?
Any thoughts on this will be highly appreciated, the operator is instructed to oil it every day. My thinking is that the coolant will be forced out by daily oiling.
Thanks,
parts

You can buy a oilier that is used to lube the table on a BP mill,or do as I did. Use a GOOD pump oil can and thread the end of the spout to take a 1/8 PIPE male adapter to use a regular Zerk grease coupler. As I recall threaded the spout 1/4"-28. Use a 1/8" pipe hex plug to make the adapter. Zerk's don't care grease oil whatever.

I bought an oil can that has a 45 degree male point, but they had no female receptacles for it, I guess I can make one.

folks use a chainsaw bar grease gun loaded with oil.

Oil is cheap, bearings expensive. Just make sure the operator sticks to the daily ritual.

I suggest you use the "button head " type fittings rather than the common zerks....these are more accurately made,and the gun fitting locks on positively ,and is easily removed......which is why they are used on airplanes....Oil in an ordinary grease gun is a bit messy ,but not a problem ,if you keep the gun in a plastic bag...........there is also a type of button head with a screw on cover ,to positively keep out dirt.

This particular lathe uses VDI QC toolholders, all of which have a small section o-ring on the VDI shaft to keep coolant out of the VDI socket.
The live tools have a tang that fits into a groove that drives it, but the coolant to holder hole is less than 1/4" from one edge of the VDI shaft, so if the operator fails to make sure every time that he changes tool holders that it actually has it's o-ring there is a small flood entering the socket with it's tang drive slot at the bottom.
There is no seal that I could see between the rotating tang drive and the ring gear behind it, and from the gear side OD past the edges into the rollers.
The system is a good example of one that should never have hit the market IMO, requiring disassembly every few months to insure that rust isn't forming and, I suppose, remove it.
The chrome at least shouldn't rust, and I'm thinking daily pressurized oil will force coolant out before rust can form inside the ring gear and the rollers.
"Use a GOOD pump oil can and thread the end of the spout to take a 1/8 PIPE male adapter to use a regular Zerk grease coupler. As I recall threaded the spout 1/4"-28. Use a 1/8" pipe hex plug to make the adapter. Zerk's don't care grease oil whatever."

Probably the easiest solution right there, the reason grease is forced in with high pressure has more to do with it's consistency, oil probably doesn't need high pressure, or as high.

I dont think you will get enough pressure with a simple pumper oil can,but try it and see.........Im a believer that if you cant see oil running out of the clearances,pump some more in till you can......If rust is a problem,there are special oils for wet machinery that positively prevent rust forming inside.

I modified a normal lever type grease gun for way oil by removing the internals from the tube end and welding the end closed to make an oil reservoir.
As long as the gun is held above horizontal it pumps the oil just fine,I checked mine with a gauge and can get near 4500 psi no problem.

Is John referring to a Bowden style oiler ?

If rust is a problem,there are special oils for wet machinery that positively prevent rust forming inside.

Click to expand...

I'll do a search on this, thanks.

There are "grease guns" meant for oil. For example Pressol 12602.

I got a regular metal oil can and attached a Zerk chuck to it, it seems to work fine.

"Push" Lube Pump for Zerk Base

Simple off the shelf solution. I bought one of these for our Delta Rockwell lathe that has zerks all over the place.

I don't know about your specific application, but I think manufactures chose oil zerks over oil cups when the oil needed to be forced into a cavity and gravity alone would not do the job. On our lathe this included some fittings for the cross-slide that if they didn't get any pressure, the oil wouldn't go uphill into the dovetail. You don't see them often on new machinery because everyone uses central lube pumps (or pressurized grease in the right application), but a zerk fitting still works fine for a local "forced" oil point that can't be easily plumbed to a pump.