Newbie here... Oil and lubrication questions...

[Mauser lover]

The SAE gear oils you will likely find will be for automotive transmissions and especially hypoid geared differentials. They have high pressure additives (sulfur) which will eat yellow metals (bronze, brass, copper, etc.) Do not use those oils in your lathe.

You can also use ISO68 gear oil, like Mobil DTE26.

Okay, I thought the ISO number and the SAE number were just different scales of viscosity? Because if that is the case it would seem that these two quotes contradict each other...

And where can I look to get a five gallon bucket for less than $30? Tractor places?

 

[Bob Korves]

Okay, I thought the ISO number and the SAE number were just different scales of viscosity? Because if that is the case it would seem that these two quotes contradict each other...

Automotive oils are commonly rated in SAE viscosity numbers. Also, some other things, like sewing machine oils. Most of the machining lubricants are now rated in ISO numbers. We are currently in a state of flux on all of this, and it can be and is confusing at times.

And where can I look to get a five gallon bucket for less than $30? Tractor places?

Tractor places, and also auto parts stores. If you go to an auto parts store, make sure you know what you need and get what you need. You can also buy it online from many of the same places we get our other machining tools and supplies (MSC, All Industrial Tool, KBC, Travers, etc.)

There are gears and bearings in hydraulic systems as well as in automobiles, but they generally require different oils.

 

[Bob Korves]

https://www.walmart.com/ip/Miles-Hytex-68-Anti-Wear-Hydraulic-Fluid-5-Gallon-Pail/49107322
Not $30 any more (been a long time) but $39.98. Have it sent to your local Walmart. Or look around. Mine was a one minute search...

 

[Lordbeezer]

Tractor Supply

 

[gwade]

I use this in my Summit lathe gear box and it runs quietly. I also use it in my MF383 tractor transmission/steering/hydraulic systems. Traveler Renew from Tractor Supply ($47.99 for 5 gals): https://www.tractorsupply.com/tsc/product/traveller-renew-tractor-fluid-5-gal?rfk=1.

 

[Mauser lover]

Automotive oils are commonly rated in SAE viscosity numbers. Also, some other things, like sewing machine oils. Most of the machining lubricants are now rated in ISO numbers. We are currently in a state of flux on all of this, and it can be and is confusing at times.

What about when both ISO and SAE numbers are listed? Check out that McMaster-Carr link I have in the top post. They have ISO and SAE numbers for all their oils, along with some other viscosity ratings that are beyond me.

Thanks for the links everyone. I'm happy with $40-50 for five gallons!

 

[mksj]

When both are listed they are the same viscosity range, so something like an ISO68 oil would be ~ SAE20 (motor oil) ~ SAE80W gear oil. So if you look on the McMasters web page for hydraulic oil they specify it as ISO68 which is pretty much the same viscosity as SAE20. The viscosity can also be expressed in other units and is specific to the operating temperature and the test used. A motor oil may operate at much higher operating temperatures than a gear oil so has different properties and often has a multi-viscosity range like 5W-30 used in a car motor. Same for car differential and manual transmission you may see 75W-90. Machines typically operate at a fixed lower temperature so do not require multi-viscosity oils. In the chart above it shows cSt and SUS which are just different forms of expressing viscosity. The bottom line is just look at the ISO number and the oil application and you will be fine with that. A 5 gallon drum is a lot of oil and shipping can be expensive. On a smaller lathe, a 1 gallon container may be sufficient. I pick up 5 gallon pales from a local oil distributor so I do not have to pay the shipping charges, so that is fine if you have a local distributor. I use Vacuoline 1409 on the ways instead of Vactra #2, I feel it works a bit better if you can source it.

 

[Mauser lover]

Okay, so in my Grizzly manual they mean ISO 68, But if they really meant gear oil, they should have said 80 on their SAE scale, because that is the matching viscosity? Their SAE numbers match as long as they didn't mean to say "gear oil"...

Yes, five gallons is quite a bit of oil. I figure I'm going to need it eventually over the life of... well... me, hopefully. So I can save a bit by buying in bulk now, when I'm just getting started in the machine world...

Plus, I lubricate everything. I probably over-lubricate most things. I change the oil in my vehicular devices more often than the mechanic instructs, so... I guess I'm just picky that way. But all that adds up to using a bunch of oil.

 

[Mauser lover]

Okay, on the grease for the gears...

I have been generally against grease for the blight of attracted dirt/swarf/everything else. Apparently it is no big deal? What about attracting chunks of the gears themselves if a failure were to happen? Or will properly applying only a little grease not be strong enough to keep a gear tooth stuck in the works if it breaks off?

Thanks for the help!

 

[Silverbullet]

Get the Lucas oil additive and use it on your gears it's tacky and great stuff. Probably like old STP use to be. I use to change an uncles oil every three months and I had to use it , he swore by it , it was an old Ford six cylinder.. God I miss unc Max and aunt Cat.