Does anyone know if Evolube (possibly Elvolube) still exists?
This is a product I remember from many years ago when I worked for an instrument calibration company, its a special lubricant for electrical contacts which I remember using on those front panel brass studs rotary switches on decade boxes and measuring bridges.
A while back I found a crumpled tube of the stuff in a toolbox I picked up at the dump, its sat in a drawer for years until now, the severe rain storms have caused problems with my motorcycle brake light switch and this lubricant (the little I have left) seems the only satisfactory way of excluding the water.
Even if the original product no longer exists, its almost certain that another brand has filled the gap in the market and I'd like to find out the name with a view to obtaining some.
I'd have thought silicone grease was the worst possible lubricant to put on switch contacts!
From past experience of light viscosity silicone spray on switches, it causes intermittent contact - and that was a toggle switch, the brake light switch supplies current to 2x 21W filaments, so arcing is a possibility which might form SiO2 on the contacts.
IIRC, there was a product back in the 1960s called "Elvalube". As I recall, it was made by Gulf Oil, and was just a pure mineral grease without additives.
Never seen any for many years. Any good quality "straight" mineral grease is as good as anything, in my experience, used very sparingly. Greases thicken over time, so it's a good idea to clean any old lubricant off before applying fresh.
--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)
"ian field" wrote in news:R19gi.5262$ snipped-for-privacy@newsfe3-win.ntli.net:
Have a look generally at PFPE's poly fluoro polyethers. You won't want the kilopoise, because the viscosity is huge, but there are finer ones. Water repellence is excellent, as is adhesion, and unlike silicones, they tend to stay where you put them instead of migrating. One possible source of a small amount of low viscosity PFPE is a scuba gear shop, it's used on the oxy tank seals.
When I last used the stuff in a job was many years ago and a long distant memory, and the tube that since came into my possession was so crumpled the label was all but obliterated, but now you mention Gulf Oil I think you may have hit the nail.
"ian field" wrote in news:9ddgi.3231$ snipped-for-privacy@newsfe1-win.ntli.net:
Polyfluoro polyethers. But Googling for PFPE will tell you more unless you like some very rarified chemistry, way over my head.
Correction to my last post, while I'm about it: it's used in the valve seals, not the tank fittings seals, though maybe both, as it's good stuff.
Apparently both PFPE and PTFE are DuPont things. How come one firm seems to manage all the advanced polymers I can easily think of, ever since the fifties? No wonder the tin-hatters say they had special rights to Roswell. :)
"ian field" wrote in news:ixfgi.7367$ snipped-for-privacy@newsfe2-gui.ntli.net:
I think PTFE greases are a suspension of fine solids. PFPE (Perfluorinated Polyethers, correction of what I said before) greases are a liquid. If you choose one with the right (lowish) viscosity, it should stay put on switch contacts, and act like any fluid, so long as it's not too viscous, the contacts should close ok. If the switch arcs from heavy currents and particles build up between the contacts, that might degrade performance, but even then a PFPE grease should help, as it will exclude oxygen as well as water. There are solvents to allow removal, so the only serious obstacle to trying one is price. They cost, so it really pays to look for a source of small tubes. Scuba gear shops had the smallest cheapest supply I could find, maybe £28 spend. Worth it though, if it works, you might not find anything better.
An example of properties of a PFPE grease:
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Fomblin Z-derivatives are widely used as lubricants in the magnetic disk drive industry to decrease the fric- tion between the head and disk, that is, reduce wear and therefore minimize possibility of disk failure.
? Chemical and Thermal Stability - limited decomposition ? Low Surface Tension - good coating, high spreading ? Low Vapor Pressure - low out-gassing ? Good viscosity index - low change in viscosity over wide temperature range ? Good re-flow properties - self coating ? Adhesion to substrate via organofunctional bonds ? Excellent Lubricity - reduce disk wear
I imagine that anything that can be used in that sensitive an environment isn't going to damage a switch, unless the switch produces its own means of destruction and the grease maintains adverse conditions created by the switch itself.
Looking at the ECL products info it would appear that Evolube is not the best choice for switch contacts. Rheogel 283 and Absolube 411A are suitable for this use however.
Its fairly obvious that I got the name wrong, its many years since I last saw the product in a workplace and the tube of it that came into my possession was so crumpled the label was barely readable - I vaguely recognised what was left of the livery on the tube and could just make out a few lines of instructions to thinly coat electrical contacts.
The reply from Fred Abse correctly names the product but googling gets no hits, so it seems likely the product is no longer available. Your suggested alternatives are well worth following up - thanks.
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