My Index Milling machine has a "Z-drive".

Catch is the upper portion selected the feed rate (0.0015", 0.003", 0.006" per revolution), lower portion has the feed gears (down, neutral, up).

Went to check on the fluid in the box (slowly seeped for years, machine had been stored outside for a while).

I didn't expect to find the upper box full of grease, lower box was obviously gear oil at one time (most of it now rock hard, thankfully some oil left).

Question is what type of oil to refill the gearbox with? Just repack the upper portion with grease? I really don't think the cover has been off since the machine was built in the 1960's.

i would guess sae #20 machine oil. that is what my lathe calls for in the gear boxes.

i had just read my manual for my old clausing lathe because i wanted to change out the oil in the gearboxes. i read that sae #20 was the oil to use. now i just looked for sae #20 machine oil and couldn't find much on it. the only one i could find was amsoil sae #20 compressor oil. i guess #20 oil is #20 oil:confused: . i guess i have some more research to do.

Sniper,

I use 20W non detergent oil for the lathe gear box. Non-detergent lets the metal particles settle out to the bottom of the gear box. My old LeBlond lathe tosses oil out, but the gearbox looks like in belonged in a Land Cruiser (stout!).

Been awhile, but #20 Motor oil is about same as #70 gear oil. So you can not be sure that #20 is #20!.

Someone was nice enough to run my request past the Mobile folks, and got this reply back from me:

>Wells-Index Division, A and D Machinery Company
>
>Muskegon, Michigan 49441
>
>United States
>
>Vertical Milling Machines
>Vertical Spindle Bearings
>Mobiltemp SHC 32 , Mobilith SHC 15
>Vertical Spindle Power Feed Gearbox
>Mobilgrease XHP 220
>Pulley Bearings, Table Lead Screw Bearings & Knee Elevator Thrust
>Bearings
>Mobiltemp SHC 32 , Mobilith SHC 15
>Knee Elevator Bevel Gears
>Mobilux EP 2 , Mobilgrease XHP 223
>Vertical Spindle Oil Cup, Knee Elevator Crankshaft Bearings, Ways,
>Slides, Spindle Quill Trip Mechanism & Automatic Lubricator
>Mobil Vactra Oil No. 2
>Lead Screws, Elevating Screws & Spindle Splines
>Mobil Vactra Oil No. 2
>Horizontal Drive Transmission, Overarm Arbor Support
>Mobil Vactra Oil No. 4

From Grainger's catalog:

Vactra No.1 SAE 10
Vactra No2. SAE 30
Vactra No4. SAE 90

Looks like the z-drive was grease at one time! :eek:

Tom