Feed screw lube

Hi,

My 3018 cnc router has feed screws with brass anti-backlash nuts. I am getting a squeal from the nuts if I try and increase the acceleration from the default.

I am using WD40 dry PTFE spray which I am not now convinced is that good. I have sprayed it onto glass and can't see any buildup, although it does feel slightly slippery on my fingers. About the same feel as after touching new clothes in a shop.

Has anyone got a suggestion for a dry lube that I could use?

WD40-PTFE needs a good shake before spraying. The can has a marble in it, which I fear indicates hard work is called for! After 15 seconds shaking I see a fine white layer appear on glass.

Graphite is an OK alternative but PTFE is less messy.

Dave

Edited By SillyOldDuffer on 17/07/2022 16:01:45

Yes, I made the mistake of not shaking it at first, but since then I have been giving it a good shake. I have even tried building it up over several applications letting it dry between.

I have seen mention of Dupont Dry PTFE that comes in a bottle, but have not found it for sale in the UK.

Use way oil. Far better...

I have the WD40 dry PTFE spray, it is good for my application. Recently, I bought a can of PTFE spray from Lidl, 300ml, cheaper, made in Germany and did a test on some polythene sheet. It is slightly greasier than the WD40, but nothing like normal sprays. It says "shake can vigorously for 1 minute".

Linear bearings where I worked specifically prohibited PTFE greases in the specifications. Dedicated way oil is best, I have just ordered a new can of Rocol Ultraglide as I have finished my previous one. I tried plain oil but had some juddering. It's not cheap though.

Martin C

I would like to ask attention for the influence of PTFE on the environment.

We know that micro plastic particles from many human processes are spread around in the environment and are finally taken up in animal and human bodies. It is a hot issue. So, should we still use PTFE as a lubricant?

I must admit: I also (still) use sometimes PTFE based lubricants, but feel concerned.

Are there lubricants free from micro plastics?

I think there are no simple solutions, perhaps bio degradable oils?

Regards,

Jouke

You make a very worthy point, Jouke … and I am certainly not attempting to make light of it … but at least we’ve come a long way since ‘Whale Oil’ would have been the preferred choice.

MichaelG.

.

Ref. __ 

https://www.scran.ac.uk/packs/exhibitions/learning_materials/webs/40/lubricants.htm

https://adtech.co.uk/fluoroplastic-products/sheet-tape-film-lubricants/ptfe-lubricants

https://fluorogistx.com/products/teflon-micro-powder-ptfe/

Edited By Michael Gilligan on 18/07/2022 07:03:42

I've used GT-85 on the feed screws of my woodworking machines for years, as the CNC is likely to get used for woodworking a dry lube will attract less dust than some of the suggested oils.

On our cnc router, we used on the main under the table lead screw a dry lube by crc. However on the Z and Y axis, I used a very small amount of the DMG mori 800 grease. Seems to work well. But mine a ball screw not Brass screw cnc. On my Myford lathe, I have put a very thin smear on the cross slide, and top slide all moving surfaces and on the lead screws. It is working very well so far.

For plastic-free lube you can use Graphite or Molybrumum Disulphide, the trouble is they are filthy. I have even seen ceramic, not sure how suitable that would be for brass on steel.

I have just found "Finish Line Dry Teflon Lube" it is sold as a bike chain lube but in the description, it says it is Dupont, so may give that a go.

In case you go looking for it, the Moly lube suggested by AdrianR is Molybdenum Disufide. It looks like a grey-er version of graphite.

The problem with all dry lubes is that they are dry and non-sticky. So they fall off or wipe off too readily.

Regards, Tim

Silicone spray?

I have ordered GT85 PTFE spray, a bottle of dry teflon chain lube and a bottle of dry ceramic chain lube. All ordered from a mountain bike shop. If they are no good my boys will get chain lube for Christmas :D

If GT85 proves successful, and you need a lot more of it, you'll often find it being sold cheaply at Aldi - I always stock up when it is.

Only noticed the other day that GT85 is actually made by the WD40 company. Smells nicer than WD40.

Rob

Edited for spelling

Edited By Grindstone Cowboy on 19/07/2022 18:45:39