Which grease?

Hi all

can any of you suggest from experience the best grease to use on my lead screws. Mo2?

It should preferably be non oxydising or dry out long term and should possess qualities that reduce wear on thread and brass nut.

We all used sae 30 in my day but things have changed Im sure

Stick with oil !

Well how do you get into the lead screws of the cross and top slide. There are no oiling holes afaik

O and btw  i dissembled my cross slide and was amazed at the flimsy Mazac nut casting which is significantly worn and the lead screw is covered in nasty black oxydised old grease that hadnt been changed for years - bad news

not impressed

Edited By brian jones 11 on 01/07/2021 18:55:21

Agree with Nick, stick with oil, grease is more likely to gather rubbish and swarf to make an abrasive paste, can you get access from the rear, squirt directly at the lead screw.

martin P

Edited By martin perman on 01/07/2021 19:00:52

You don't say what the lathe is, but the comment about Mazak nuts points towards a Myford. If that's the case, wind the cross slide and top slide out most of the way, then use the spout of an oil can to lubricate the screws from below.

sorry its an ML7 with a sML7 cross slide - maybe i can add this to a regular footnote

No one suggested drilling an oil hole in the apron casting above the lead nut then?

come to think of it, all those years i never touched the compound slide lead screws in all the machines i used

Wow that piece of information about the Myford lathe has made my day, my never to be metioned in conversation Clarke CL500M has an oiling point directly above the cross slide nut which has a hole through the nut support post to allow oil onto the cross slide thread

Martin P

Yes MP I went out to check I hadnt had a" stoopid boy Pike moment" I dont see any oiling holes in either slide

Doing some more digging there are some synthetic greases on the market which are loaded with PTFE particles specially made for "power screws". I saw this on the lead screws used for x-y tables for DRO milling

FYI the pitch on these is generally 2mm but it can have 4 starts giving a lead of 8mm - impressive precision from EB

I came by some 3ft lengths of 1,5 bsw threaded rod cw full nuts. I had in mind to make a screw press (like a cider press)

then I did some digging and discovered how little force you got for your effort . You could lose up to 70% of force due to friction from the threads, which is why acme threads were invented

Then I thought - its easy to make an acme threaded rod - but what about the nut?

3/8" x 10 tpi LH acme die from a well known supplier (but he doesnt offer the tap to go with it) - cant have punters making their own nuts

Now here's a rare sight 1/2" acme 10 tpi

LH of course from EB £10 2u

If you service your Myford Super 7 cross slide regularly, as you should, then the screw can be oiled at the same time as the dovetails are dismantled, cleaned and lubricated.

The same applies in principle to the top slide although I suppose they are wound in and out much less.

If grease were desirable for either I think Myford would have said so in the manual.