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cuemaker
07-24-2006, 02:34 PM
and for the parts that are not oil bathed, what kind of grease should I use?

The parts I am talking about are the gears in the saddle that move along the feed screws. The connection between the feed screw and the ?bronze? bushing?

etc.

If I have opened up a can of worms and you need more specific questions, let me know.

topct
07-24-2006, 05:11 PM
What does the book say to use?

Boat trailer axle, roller bearing grease........ works for everything. :)

cuemaker
07-24-2006, 05:14 PM
ok, so nothing critical.

I know what the book says for oil, shell tellus 32 or something like that. But i dont remember the grease part.

Evan
07-24-2006, 05:22 PM
I would use thin grease. Really thin grease. In fact so thin that it resembles oil. In fact, use oil. Chips have a habit of getting anywhere and grease will glue them there. Unless the unit is sealed the chips will get stuck in the grease.

SGW
07-24-2006, 06:13 PM
Oil. At the slow speeds most of the parts move, oil will stay put.

BadDog
07-24-2006, 06:54 PM
They also make a special grease for use on exposed gears and chucks that is a heavy tar like substance. It is supposed to keep chips from sticking, and has "self healing" properties such that it closes gaps made by gear mesh and the like. I've been looking for some Mobiltac 375 NC (and there are others like it) for use on my QCGB and gear train as well as chucks.

Evan
07-24-2006, 07:43 PM
Non sticky grease sounds like an oxymoron.

Fasttrack
07-24-2006, 08:00 PM
So does jumbo shrimp but its still on the menus ... :D

BadDog
07-24-2006, 08:02 PM
All I know is that is the claim. It also came up in reference to being the "preferred" grease for chucks for the same reason. VERY high film strength, self repair, and low chip retention all sound pretty good for the application, assuming it works as advertised. Apparently Dow, Texaco and several others make such things including some marketed specifically as "chuck grease". The Mobile stuff (google it for more info) sounds enticing and I would like to try it, but can’t find it at the usual suspects and “Mobil Dealers” sell only 5 gallon drums.

nheng
07-24-2006, 08:30 PM
Oil is cleaner and much easier to "renew" than grease. I use way oil for everything (apron, ways, tailstock) except the QCGB and the headstock. The mfgr called out DTE26 but the way oil stays put and is very compatible with ... the way oil :D

For the chuck, I've had good luck (read: no black streak down my shirt) with thick, black, moly based disc brake grease. From my limited experience with several chucks (greased with expensive chuck grease at the factory), the chuck grease seems to hold swarf with the best of them.

Evan
07-24-2006, 09:02 PM
I use oil only. I use a lot of oil. The only problem I have with oil is that I have to wipe off the excess from time to time. My lathe is covered in oil.

speedsport
07-24-2006, 09:07 PM
Evan,
Did you ever try using oil?

lazlo
07-24-2006, 09:09 PM
All I know is that is the claim. It also came up in reference to being the "preferred" grease for chucks for the same reason.
...
as "chuck grease". The Mobile stuff (google it for more info) sounds enticing and I would like to try it, but can’t find it at the usual suspects and “Mobil Dealers” sell only 5 gallon drums.

BadDog,

When you asked about this on PM, Matt Isserstadt and I warned you how sticky Gearshield and/or Mobiltac is! The Open Gear lubes have tons of additional tackifiers added, so they are very sticky, hence the use for open gears (so it doesn't get slung off).

Chuck grease has 25% Molybdenum Disulfide. Very different animal.

http://ecommerce.ntwhi.com/productDetails.aspx?ProductID=801


Robert

Evan
07-24-2006, 09:13 PM
The trouble with moly filled grease is the staining potential. That stuff is worse than printers ink. It migrates everywhere.

speedsport
07-24-2006, 09:33 PM
"It migrates everywhere", kinda like mexicans huh?

BadDog
07-24-2006, 11:27 PM
When you asked about this on PM, Matt Isserstadt and I warned you how sticky Gearshield and/or Mobiltac is! The Open Gear lubes have tons of additional tackifiers added, so they are very sticky, hence the use for open gears (so it doesn't get slung off).

Are you talking about this thread?
http://www.practicalmachinist.com/ubb/ultimatebb.php/topic/1/23766.html#000010


If so, I just re-read it and I must be misunderstanding both of you.

Matt commented on several different points of my lube question, including the Mobiltac. Other than the chain comment, I don’t see anything negative and he also comments on using an “open gear lube” himself, though a different brand (Lubriplate). Unless I misunderstand, they are both open gear lube and have similar properties if different application mechanisms.

That was his only comment in that thread.

You commented on several points as well (much appreciated I must say). Specifically the Mobilith SHC 220 which was great in that it confirmed my own inclination to use that product. You also commented on using “Lubriplate Gear Shield Extra Heavy” as a replacement for Mobiltac which you didn’t think was available any longer. And I see no other comments on the Mobiltac other than a few more on the same topic.

Am I missing something?

In any case, as I've stated, I'm repeating the Mobile propaganda, I have no knowledge of whether it is better or worse than anything else at rejecting chip contamination.

SJorgensen
07-25-2006, 12:52 AM
Depending on the lathe you might want to use grease on some gear parts. On my SouthBend 9" model A the change gears can be noisy. These aren't real precision gears. Some old timers recommend putting saw dust in the gears to create a cushioning effect. It works pretty well with sawdust and grease.

Evan
07-25-2006, 01:40 AM
You aren't supposed to run the change gears at top speed Spence... :D

speedy
07-25-2006, 07:54 AM
Shell Malleus GL ( Shell Canada). You don`t need much, it goes a long waaay, it quietens gears and SLSTAB.

Zuesdawg
07-25-2006, 09:18 AM
Although Im new to machining... lol, it gives me time to experiment based on the advice given in this thread. Tried oils, grease, ect...

but am having the best luck with BG Rear End Lube Oil

just dont use the friction modifier... stuff stinks to high heaven

cuemaker
07-25-2006, 10:45 AM
Some of the parts are protected to some degree. Specifically the gears ans stuff in the apron.

Here is my problem with oil. Its more likely to get on everything. Once I am done "reconditioning" the lathe, its primary purpose is going to be cutting wood and plastic. I cannot have oil on my wood or plastic.

The reason grease seems to be a bit more "safe" is that its more likely to stay where I put it and continue to do a good job.

Rex
07-25-2006, 10:46 AM
I'm with Evan. For home hobbyist use, I don't think it's neccessary to use THe Exactly Correct Lubricant. If you run a production shop, that's different, but then you probably wouldn't be here.
I use synthetic motor oil and ATF, mostly because samples wind up on my desk regularly. The only place I use grease is the change gears. There, I found a small amount of 5th wheel grease (another sample in a small squueze bottle) worked incredibly well to quiet it down.
I also add oil ports liberally. The 7x10 I just acquired had nasty grease all over it. I cleaned it out, oiled liberally on reassembly. I will order some of those ball oilers so that I can add oil to the crossfeed and compound screws, as well as the halfnuts and a few other places.
My Logan does use a crossfeed clutch, and I try to keep the correct oil for that because it can affect operation. But I've used whatever was handy and it's always worked fine, so I don't lose sleep over it.

Vacuum chips, Over-oil, wipe off excess, cover.
The pleasure of a well-oiled machine.

JCHannum
07-25-2006, 10:58 AM
Some of the parts are protected to some degree. Specifically the gears ans stuff in the apron.

Here is my problem with oil. Its more likely to get on everything. Once I am done "reconditioning" the lathe, its primary purpose is going to be cutting wood and plastic. I cannot have oil on my wood or plastic.

The reason grease seems to be a bit more "safe" is that its more likely to stay where I put it and continue to do a good job.

Grease, or light grease might work OK in that situation, as any chips it might attract would not tend to cause the damage metallic chips would. But, in some applications, grease will "pile" up on the side and not penetrate sufficiently to lubricate the part. You can put all the grease in the world on your change gears, but if it does not reach the shafts and bearings, it is useless.

The only way oil gets on anything is if it is overapplied. Oil in or on the apron and change gears will not get on the workpiece unless it is in such large quantities that it is being slung everywhere. Too much of any lubricant will have the same effect.

If experimenting with lubricants, it is wise to inspect the machine parts from time to time to see if they are indeed being lubricated properly. The purpose of lubrication is to protect the machine. You may have to try several different combinations and application schedules if your situation is different than that of the normal HSM to acheive the desired balance of good lubrication of the lathe and clean parts.

There are several non-staining greases, and white greases. Lubriplate makes some, and it might be worthwhile to look at their products. Working in the food industry, we had to use FDA approved lubricants. They did an adequate job, but had to be replaced frequently to maintain their effectiveness.

Apply the proper lubricant, wipe off the excess and have at it.

cuemaker
07-25-2006, 11:05 AM
So basically I am putting to much thought into it, especially since I already aware of any problems or potential issues. Got it.