Dial gauge lubrication?

[Prowe]

I have always been led to believe (perhaps incorrectly) that dial gauges should not be lubricated, but I now find after years of use that I can longer trust any of mine because they have become so stiff in use. I am now beginning to think that like a watch or clock they should be dismantled, cleaned and lightly lubricated with appropriate clock/watch oil. As we are blessed with a very wide spectrum of experience on this site, I’m wondering what the general feeling on this matter is.

Many thanks to the administrators and contributors who make this such an interesting and informative site and I wish you all the best for Christmas and the New Year.

Regards to all,

Phil

[kingsteam9]

Phil,

I've experienced the same problem with an old Mitutoyo dti which was decidedly 'sticky' in operation, and did the strip, clean and lightly oil routine. It works ok but at times there is a noticeably slow response - possibly more apparent at low temperatures (my workshop is part of an unheated garage). I don't doubt the accuracy but the problem now is one of obtaining consistent readings, with the needle not always returning fully to the stop. Needless to say in mid summer it performs ok. If I was doing it again I'd think twice about using any form of oil and possibly explore an alternative lubricant - needs a bit of experimentation I think.

Robin

[Richmond]

Hi,

The chemists amongst us will probably shoot me down on this. However, my old toolmaker mate tells me that he uses purified castor oil ( BP ) available from most chemists. Worked for me, as well as removing ear wax !

Seasons greetings to you all!

Keith

[DaveW]

A good clean helps with perhaps a tiny drop of watch oil on any plain bearings but the most usual cause of extreme 'stickiness' is wear to the pin that locates the rack. This slides in a slot bearing to keep the rack on the main shaft in line with the gearing and over time can develop a rough surfaced flat. If it's not too worn it may be possible to file and polish it back to a single point contact.


Dave.

[SteveW]

Guys,

A word on cleaning these things. Years ago I watched as a guy at work decided to clean the workshop clock. He used meths and ended up dissolving the lacquer on the frames which promptly got drawn into all the bearings. Time stood still so to speak.

I've had some success using the Screwfix dry PTFE spray lub. Conscious for Ally-Palley MEX very soon, I've also seen clock oil on either the Proops or the other lot's stand.

[tomol409]

Prowe, I have found that silicone spray is an incredible lubricant. The two fans in the flame effect of my electric fire were constantly sticking. Three years ago I sprayed the spindles with this and they have never ceased rotating since. The fan on my central heating flue stuck and the spray freed it and it has been now going for a year.
I have found that on two of my older gauges the plunger was causing them to stick, and the spray being very thin was able to penetrate and free them up nicely. Tomol.

[Prowe]

A quick update on the lubrication question.
Over the holiday I dismantled a “Baty” plunger type dial gauge that I bought many years ago in a club auction that had apparently come from an apprentice training facility. Without doubt there was quite a build up of sticky “gunge” on the plunger itself, after cleaning it with IPA there was a marked improvement, but still one or two sticky points over the course of the travel. I then noticed that the rack and pinion has a facility to allow the meshing to be adjusted or “depthed” as clockmakers would say, after making a few adjustments with the meshing, I find the dial gauge now works perfectly smoothly over the entire travel.

A Happy New Year to you all.

Phil

[engineernut]

My two-penny worth on this I expect will get shot down, but any detrimental thought would be appreciated for future reference.
I purchased an old Mercer DTI gauge last year at a local steam exhibition and this was sticking quite badly (only paid a few pounds for it).
It sat on a shelf in the workshop until just before Xmas when I decided to have a look at it. Tried slight lubrication which although showed improvement was still nowhere near perfect.
As a final try before stripping it down I immersed it in White Spirit. The spirit was quite dirty when it drained off but the gauge worked perfectly, and still does so far four weeks down the line.
Although initially I did think the spirit would turn sticky when dried out fully but there is no sign of that yet, and if it does will then try the PTFE spray.
Dave

[jonkett]

I managed to have a word with our metrology department today, and they use a product called microtime to lubricate dial gauges after repair.

This i believe is a very light watchmakers oil as they obtain it from a company called Southern's Watch/clock makers supplies.

Hope this helps.

[miken]

When I was an apprentice I was told you should lubricate a dial gauge with powdered graphite.
But ive never tried it.
Mike