Lube DMM Selector Switch?

[metrologist]

My old Micronta 22-167 failed to read ohms due to dirty selector switch. I opened it up and cleaned with rubbing alcohol (IPA) and now wonder if I should apply some lube to reduce wear? WD-40?

[BradC]

Wd40 is not a lubricant. Additionally don't use petroleum based products around plastics if you expect any form of longevity.

[Lightages]

WD40, means Water Displacement formula #40. It was a chemical soup dreamed up to remove water from surfaces. It is not a lubricant and should NOT be sold as such, but money speaks. Do not use it on anything you care about. It is slightly corrosive and attracts dirt and dust like crazy. It has very little lubricating properties.

Use WD40 for displacing water, freeing up siezed bolts nuts, or other fitted parts, then clean them and apply a proper oil, grease or other lubricant.

There are dielectric greases that are used for switches and such but I do not have experience in sourcing them.

[Electro Detective]

Lightly apply WD40 with a cotton bud  if that's all you have till you get something appropriate

Otherwise you'll have bigger problems due to friction and wear as the IPA has washed the lube away

[Lightages]

Regardless of what Electro Detective says do not use WD40 in a multimeter especially. It is not a dielectric lubricant, will attract contaminants and can cause the safety rating and accuracy of your meter to go down. It is one of the worst things to put inside your DMM. It is also flammable. Do I need to say more?

[Lightages]

https://www.amazon.com/Permatex-22058-Dielectric-Tune-Up-Grease/dp/B000AL8VD2

Use it sparingly

[xavier60]

I have been using PAO synthetic oil on switch contacts for many years with good results.

[Electro Detective]

Regardless of what Electro Detective says do not use WD40 in a multimeter especially. It is not a dielectric lubricant, will attract contaminants and can cause the safety rating and accuracy of your meter to go down. It is one of the worst things to put inside your DMM. It is also flammable. Do I need to say more?

More anti-WD40ism       (())   

If OP applies it with a cotton bud, it's only the LIGHT lubricant that will remain, to ensure minimal selector track friction,
and adequate contact till OP can source an appropriate lube.

LIGHT lubricant means it won't attract any more contaminants than any other lubricant would,
and nothing is going to catch fire unless your suburb gets napalmed by a nest of mutant fireflies,
or the multimeter gets tossed on the BBQ along with the usual cadavers during an after work beer binge session.

Try it for yourself on any similar material/s and plastics before taking the plunge,
it smells like petrol yes, but that soon goes away.
Do a metal to metal resistance contact measurement as well, and see what happens.

There is way too much WD40 paranoia, it's not an aggressive product as some others,
and common sense dictates if you've got nothing else to bail you out,

it's better than nothing   

[mikerj]

WD40, means Water Displacement formula #40. It was a chemical soup dreamed up to remove water from surfaces. It is not a lubricant and should NOT be sold as such, but money speaks. Do not use it on anything you care about. It is slightly corrosive and attracts dirt and dust like crazy. It has very little lubricating properties.

People seem to enjoy repeating  this like sheep, especially on car related forums where it apparently isn't a penetrating oil (it is), it has no lubricating properties (it does) and is generally evil (it isn't).

I would be the first to state that it's not really the correct stuff to lubricate switches.  However it's basically a light oil in a solvent, the same as most other penetrating oils, so has very similar properties, i.e. fine for very light duty lubrication, freeing of rusty/stuck parts and it's excellent at removing heavy oil and grease.

I'd go for a proper switch cleaner/lubricant such as Servisol "Super 10", and use it sparingly.

[Electro Detective]

Exactly     I have Servisol, WD40 and just about every other tinned formula required for electronics, automobile, garden tools 
...and anything else where friction may need sorting 

I have used WD40 in OP's application to lube rotary selector tracks on a meter when I didn't have another option, with long term SUCCESS,

otherwise I would not be recommending it as a short term fix.

[Gyro]

Personally, I really wouldn't contaminate things with a short term fix, followed by the necessary clean up!

Order the correct product and be patient for a few days.


P.S. The best contact cleaner/libricant I've found is Electrolube EML (in fact Electrolube have a whole range of contact lubricants, many of them for very specific automotive applications (at manufacture). EML doesn't have all the Audiophool hype of Deoxit but is just as good - Don't get me wrong, Deoxit is an effective product but seriously, just compare the product datasheets! 

Electrolube SPG is a really effective lubricant for plastic parts, detents etc. It's worth having some of that around too.

[alm]

I would be the first to state that it's not really the correct stuff to lubricate switches.  However it's basically a light oil in a solvent, the same as most other penetrating oils, so has very similar properties, i.e. fine for very light duty lubrication, freeing of rusty/stuck parts and it's excellent at removing heavy oil and grease.

The problem is that the solvent removes any existing lubricant, and the light oil will evaporate soon. Leaving an unlubricated (is that a word?) joint. So the correct statement is that it does not lubricate for long .

[SeanB]

I tend to use Shell Cassida, as it is sold as safe to use on nylon, plus it is white, food safe and I use it a lot at work as a general purpose grease. Being safe on nylon parts makes it a good lube on switches, as they tend to use nylon or bakelite parts as insulators or spacers, though the cheaper ones use ABS plastic, which is very brittle with time and stress with any lubricant.

http://www.gannonoils.co.uk/images/stories/shell-cassida-grease-eps.pdf

[Lightages]

So its one person's word and experience against another.... I say there is a problem and others say there isn't. I have experience that makes me say what I say and the others have experience to say otherwise. AMP Connectors did a study on the effects of WD40 on their connectors in the 1990s. The conclusion was that WD40 was corrosive in the long run, attracted contamination, and was recommending that all of their customers not use WD40 for lubrication nor for protection.

People can believe what they want, but usually where there is smoke there is fire.

metrologist:
Do you what you think is best for you but please follow up with some more research of your own and ignore me and the others. I don't think you will find a consensus here.

[stj]

o.k. get ready for a flame-fest or tears.

i am a repair engineer working on pcb's upto 40years old.
i have seen WD40's work up close enough times.
IT IS A PCB DESTROYER!!

NEVER put it on a pcb or spray it into chipsockets - specially into chipsockets.
it's a penetrating oil - and it does.
it slowly gets under the tracks and eventually lifts them off the fiberglass matting.

any pcb that has been contaminated with WD40 must be washed with a de-greasing agent as soon as possible.

i'll just add that i dont give a shit if you dont believe me, it's your pcb's and if they ever end up on my desk they will probably be turned away.

[stj]

btw, the correct thing to use on sliding contacts is contact lubricating grease - any good supplier should list it.

[Gyro]

I tend to use Shell Cassida, as it is sold as safe to use on nylon, plus it is white, food safe and I use it a lot at work as a general purpose grease. Being safe on nylon parts makes it a good lube on switches, as they tend to use nylon or bakelite parts as insulators or spacers, though the cheaper ones use ABS plastic, which is very brittle with time and stress with any lubricant.

http://www.gannonoils.co.uk/images/stories/shell-cassida-grease-eps.pdf

FWIW, Electrolube SPG (Special Plastics compatible Grease) is an ABS compatible lubricant. They also produce SPGA, specifically for for ABS and polycarbonate which is more adhesive to the surfaces (but that one only appears to be available in 200l tubs!)

http://www.electrolube.com/search.html?sitesearch=spg

Electrolube stuff also seems easier to source in the UK - RS, Farnell etc.

[metrologist]

metrologist:
Do you what you think is best for you but please follow up with some more research of your own and ignore me and the others. I don't think you will find a consensus here.

One thing I think we agree on is that there should be lubrication 

I had a distant memory of seeing permatex silicone based dielectric grease so went rummaging around my shop and found the tube. I applied a light coating to the tracks with a toothpick.

The meter was failing to read resistance and jiggling the selector made the reading jump from Mohm to kohm on a short. Now it is working well. Thanks all.

[eKretz]

Please do not use WD-40 on electronic devices that you value. I too have used the stuff for decades as well - and it is very useful *in applications that it's suited for!* Sensitive electronic devices are not one of these. For mechanical movements that aren't too finely constructed or for cleaning gunk from same - it works great. Ignore Electro-Detective, he has been outed as an instigative troll even by Dave.

[stj]

while we are on the subject of lubes.
does anybody know what the fine mint-green stuff is that used to be used in vcr's on the plastic gears and sliders??
i wouldnt mind a pack of that. 

[Gyro]

I always suspected that it was something that exuded from the kids when they were toddlers! They used to post all sorts of stuff into ours.


P.S. I remember the grease was black in early Ferguson top loaders, presumably something Moly based. I guess you can work out from the above posts what I would recommend as an alternative.

[SeanB]

while we are on the subject of lubes.
does anybody know what the fine mint-green stuff is that used to be used in vcr's on the plastic gears and sliders??
i wouldnt mind a pack of that. 

Probably available from Matsushita as a service part, or from Sony as well. Slide lubricant, probably a molybdenum sulphide based additive with a non tacky base lubricant and metal soap thickener.

The black one is similar, just a molybdenum disulphide based additive ( black) in a similar base. a good substitute is to go get a tube of Molyslip oil additive, though I will warn you it is hard to get out of your fingers afterwards and it permanently stains clothes.

[stj]

not from SONY, those assholes used regular "golden" grease that hardened over time and jammed everything up!!

[Electro Detective]

Please do not use WD-40 on electronic devices that you value. I too have used the stuff for decades as well - and it is very useful *in applications that it's suited for!* Sensitive electronic devices are not one of these. For mechanical movements that aren't too finely constructed or for cleaning gunk from same - it works great. Ignore Electro-Detective, he has been outed as an instigative troll even by Dave.

More baiting? 

I never recommended OP to use it on 'sensitive electronic devices' which implies spraying it on, which is a no no.
If eKrutz READ the comments above in sequence rather than engage in continued butthurt underhanded troll calling (from ONE post Dave outed me from) I stated apply 'with a cotton bud', which means only the light lubricant remaining will be applied, and none of the carrier solvent.

I have used WD40 (and all the rest of the magic sprays and greases) wisely for decades too btw


The original post again:

My old Micronta 22-167 failed to read ohms due to dirty selector switch. I opened it up and cleaned with rubbing alcohol (IPA) and now wonder if I should apply some lube to reduce wear? WD-40?

A "dirty selector switch" requiring a temporary lube is not 'sensitive electronic devices' and if OP only had WD40 on hand, it would have done the job till sourcing something suitable suggested by members above 

If OP metrologist thinks I'm pulling his leg and wishing harm to his meter or 'instigating' anything, I will remove all my comments immediately   

 

[Electro Detective]

.

Quoting Youtube poster AllAmericanFiveRadio


"PANASONIC model RF-800 1964 This was the first time I used WD-40 for this purpose.

I'm being conservative with the years it's much closer to fifteen years ago.

I had tried many tuner cleaner products, and some worked for awhile, some did nothing and others made it worse. I have had zero problems.

I do not spray the WD-40, I use an eye dropper, or a small screw driver to apply just a few drops where I want them."



Many more Youtube replies have similar positive experiences at youtube.com/watch?v=lyjUDh7Djpo