Lubrication For Lathe Headstock

[pete]

Properly engineered lubrication products are a complex science. Luckily we only have to understand a bit of the logic and physical properties behind that engineering for the lubrication products we might be using. High detergent oils such as those used in automotive engines are designed to keep any contamination suspended in the oil until it hits the filter. Very few home shop sized machine tools would have a pumped and properly filtered lube system. So a non detergent oil is desirable since it allows any wear particles to drop to the bottom of the sump and hopefully remain there until there flushed out at the next oil change. Adding a magnet to the sump can help if it's placed where there's no chance of any gear contacting it. That obviously won't help with any non ferrous particles though. Clean diesel fuel works well for flushing out anything sitting in the bottom of a sump. I hate to second guess any machine tool manufacturer or even a dealer, but Shopmasters recommendation and use of that Marvel oil is the first time I've run across the recommended use of any high detergent oil in a head stock sump. Given the little I'd like to think I understand about lubrication I'd still question there logic about using that type of oil.

It may or may not not be part of the issue, but any semi sealed oil sump will have a vent somewhere above the usual oil level. It's required so as the head stock warms up or cools down the air pressure within that sump stays at the normal atmospheric pressure. If that vent becomes plugged the higher internal air pressure as the head stock warms up can force oil through the weakest point (that seal) If it were me I'd double check that vent is clear or even if the hole was drilled in the first place. Your lathe wouldn't be the first one I've seen a post about where the vent hole wasn't drilled at the factory.

[John Hasler]

Detergents don't suspend wear particles, just combustion products. I don't think that they will do anything at all positive or negative in a gearbox. I agree that MMO is a wierd choice, though. There must be a light gearbox oil with an EP additive out there.

[pete]

Your correct and I used a slightly wrong choice of terms I guess.

[Steggy]

He told me they use "Marvel Mystery Oil".

aka Snake Oil. A good quality, non-detergent SAE30 motor oil will work well...after you fix that leak.

[John Hasler]

SAE 5 would be closer to the viscosity of MMO.

[Steggy]

SAE 5 would be closer to the viscosity of MMO.

True that, but too low for use with any machine fitted with tapered roller bearings, ABEC 5 or ABEC 7 ball bearings.

[16WhiteColly]

When I asked Grizzly Tech Support what HL-70 Gear Oil was, they told me they recommend 30W Non Detergent Motor Oil for the headstock on the 9729.

I am sure David Brown is going to be happy to have this information as it has been a 17 year wait to date.
[emoji846][emoji846]

Sent from my SM-N975F using Tapatalk

I realize that it will not help David Brown, but was just sharing information on the HL-70 subject, since it is vague on the recommendation and a question that has been asked often. Maybe I should just read and stop posting.

[NP317]

Don't stop posting.
I found the info about equivalence between those two oil designations to be quite useful, and made notes in my lathe Op. Manual about it.
Thank you.
RussM

[AllenH59]

I use engine oil in my my lathe headstock.. This reminds me it might be a good time to change it.

[John Evans]

I use engine oil in my my lathe headstock..

Bad idea if you are using detergent oil !! That is made to suspend wear particials until engine oil filter can remove. Non-detergent would be OK . I use tractor hydraulic fluid which has anti foaming and wear properties ,also good for most other lube points other than the ways.

[whateg0]

I use engine oil in my my lathe headstock..

Bad idea if you are using detergent oil !! That is made to suspend wear particials until engine oil filter can remove. Non-detergent would be OK . I use tractor hydraulic fluid which has anti foaming and wear properties ,also good for most other lube points other than the ways.

I have read several discussions where experts have argued over the use of detergent oil in machines. While many seem to lament the suspension of wear particles, I've seen many also say that particles are not suspended in such a way that they circulate through the system again. They say that the detergent is there to keep combusion byproducts (which I suppose could also be particulate, such as carbon) in suspension.

Dave

[John Evans]

The few times I have seen a makers recommendation for engine oil use it has always been for Non-detergent oils ,usually about 20WT.