Switch cleaner.

[Paul JD]

Originally Posted by Herald1360

Trichloromethane, "trike", was the "go to" general degreaser back in the days.

I imagine you mean trichloroethylene, trichloromethane is chloroform.

[bluepilot]

I remember back in the 1970s using trike when making printed circuit boards. We used UV sensitive resist and work took place in a yellow transparent tent to keep the UV out. Also kept the trike fumes in. A few breaths and we were completely inebriated. Can't say I ever felt like complaining.

[Alistair D]

If anyone has access to he August 2012 issue of Practical Wireless Harry Leeming published an interesting article on switch cleaning. and getting good long term results.

I do have that issue of P.W. here but, due to mobility issues. I am not sure when I will be able to scan it.

This article will almost certainly still be covered by copyright so I will check with the mods if I can post it here. The alternative would be PMs and email.

Al

[Hartley118]

Originally Posted by 2000 type

WD-40 was specifically banned from BT telephone exchanges. There was probably a good reason......

That’s surprising because I understand that WD40 is basically white spirit, and my memory of working in a telephone exchange is that all contacts were cleaned with white spirit. But that was then (1960) and policy may have evolved!

[2000 type]

There were other chemicals and additives in it - something to do with fish oil if I remember, but one big problem was that the manufacturers wouldn't reveal exactly what the composition was. The volatile elements would dry out leaving a sticky residue that was not good on light contacts.

I recall the ban being promulgted in one of the engineering maintenance bulletins.

Regarding white spirit, in a very old (1929!) Strowger exchange I worked in as an apprentice (known as a Youth-in-Training), selector bank contacts were cleaned with a mixture of about 6:1 white spirit and Oil, Bearing No.16 (known locally as "slosh") applied with a specially curved toothbrush, then dried with an absorbent tape. The bank insulators were of fibre material.
The exchange remained in service until the 1970s so it apparently worked without causing too much damage.

[Bazz4CQJ]

I don't think the Classic WD40 product was ever promoted as a contact cleaner.
I recall it first appearing around about 1976 and it was sold mainly as a aerosol lubricant for use around the house/garden/garage. I don't recall a comparable aerosol being on the market before that. I've never used it as a contact cleaner... and never would.

There are a few people for whom the very mention of "WD40" seems send their blood pressure soaring, and will blame all kinds if ills on it, and I really don't share those views.

There's no doubt that some of the best contact cleaners were to be found among the ozone-depleting compounds, but they are long gone (from public sale) and we have to find and make do with the best of what's now on the market.

B

[G6Tanuki]

Original WD40 was around in the mid to late 60s, when it was sold as a spray on treatment for damp in car HT systems, along with products like Holts Dampstart and Contect Duck Oil.

The WD part of the name standing for Water Dispersant.

I first came across it in Texas in about 1970 where it was used as a treatment for outboard motors after they had been used in salt water. You bought it in gallon cans and applied it using a garden pump up pressure sprayer.

Its use as a general purpose cleaning and maintenance spray came later.

[DrStrangelove]

Rocket WD40!

Accept no substitutes for use with your Atlas missile!

https://www.wd40.com/history/

Note: do not spray on the thing at the top inside the pointy bit.

[HamishBoxer]

I thought WD40 had silicon it, I used it way back on wet ignition leads and for trying to free rusted up bolts etc. Never on switches, DE-Oxit fan, not cheap but works and needs very little.

[G6Tanuki]

No, the original WD40 is silicone-free; indeed this is marked on the can!

WD40 company *do* now offer a silicone based lubricant in their product range though.

[ppalped]

I was with the impression that Fluke somewhere in the past recommended WD-40 for cleaning the terminals of their meters. I wasn't really sure, so I had to go through old stuff to confirm:

- Fluke 80 Series V, User Manual Rev 2, May 2004, page 35, Section General Maintenance: "Soak a new swab with a cleaning and oiling agent (such as WD-40). Work the swab around in each terminal."

In more recent manuals (either user or service for any given type of equipment) they seem to recommend IPA for cleaning the terminals.

I never used WD-40 (the original, blue can) to clean terminals anyway. Only WD-40 Contact Cleaner - that is a completely different product and the only similarities between the two start and end with the WD-40 prefix.

Alex

[Welsh Anorak]

I've been quite impressed with the WD40 Specialist contact cleaner, available from CPC and, usefully, Screwfix.

Original WD40 is handy for garages, but we always used to sniff a customer's VCR that came in for repair. A liberal coating of WD40 meant a liberal application of pen to invoice book many hours later!

The best contact cleaner I used to get was the Philips one which didn't melt plastic. Although Servisol was ubiquitous back in the day, squirting it onto a plastic GEC solid state TV's channel buttons resulted in them and the on/off switch vanishing into the depths of the cabinet a week or so later when the original 'repairer' had galloped into the sunset.

[Oldcodger]

I've not read all the previous posts, so excuse me if this is a repost. Anyone PO/BT of circa 1970 , possibly ex Leeds will remember the ( 24/60 channel carrier) where one of the line amps ( providing NFB o the system ) had a nasty habit of the contacts going HR and the gain increasing . To cure this, sometimes a quick twist of the switch was sufficient. Other times it needed a good squirt of switch cleaner. But one brand in particular caused more problems than it solved.

[Alistair D]

Originally Posted by Alistair D

If anyone has access to he August 2012 issue of Practical Wireless Harry Leeming published an interesting article on switch cleaning. and getting filegood long term results.

I do have that issue of P.W. here but, due to mobility issues. I am not sure when I will be able to scan it.

This article will almost certainly still be covered by copyright so I will check with the mods if I can post it here. The alternative would be PMs and email.

Al

I now have the PW article scanned and converted to PDF. The mod team (thanks David) has suggested that there could be copyright issues putting the article online. What I had forgotten was that the file would be too large to post it on the forum anyway.

So, if you want a copy please PM me an email address.

Al

[samjmann]

I used Philips contact cleaner for years. It was the one of choice over Super 10. Philips spares stopped selling around 2008 I think or maybe earlier. Chances are it was marketed by Philips, rather than their manufacture. Maybe Sideband might know on this forum. SJM.

[knobtwiddler]

The Philips being discontinued led me to discover Deoxit. I was going to remark about how well I found it to work, but didn't as I recalled the anger I felt when I couldn't get it anymore and didn't want reminding.