Servicing your lighting switches etc, discussion not problem
Posted: 16 Nov 2015, 13:12
I got asked this in a pm, and thought I would share my thoughts on it.
OK, firstly I must say that in my experience (40+ years), "Switch Cleaner" as we generally know it is very little help when it comes to "servicing" 12 Volt lighting (etc) switches. Most of the stuff you can buy (Servisol, Maplins etc) is NOT designed to do much at all to the relatively heavy contacts found in normal automotive switches. It is designed to "service" the likes of volume controls (etc) on Hi-Fi systems etc, where it cleans the delicate carbon track and coats it in lubricant that is especially geared towards carbon tracks and the associated brass "wiper". It can be effective in delicate multi-contact switches (as found in Hi-Fi etc) to a lesser extent.
When you consider what goes on inside a 12 Volt lighting switch though, one can see why it is of little use (imho). We have some fairly heavy duty lumps of brass that make a firm contact with each other via a spring. These contacts "arc" a little every time they are used, much like the rotor arm of a vehicles distributor. This arcing causes both erosion of the mating surfaces and a build up of pretty solid / crusty carbon deposits. In my opinion, no spray is going to do much to help rectify either of those two symptoms of a dodgy switch (of that type).
I have also personally seen Servisol virtually dissolve certain plastics (I once ruined the plastic jack plug sockets on a guitar foot peddle with the stuff), so I can't recommend that (other than for most volume potentiometers).
If I was going to spray something onto 12 Volt vehicle switches, it would likely be this = "DP60" on Ebay, but in reality, if I had a suspicion a switch needed attention, I would either strip it, clean the contacts by scraping them and lubricating the moving parts with a light application of Vaseline or simply replace it.
Hi John
There seem to be loads of products on the market for cleaning electrical switches. Have you got a recommendation for the best one for light switches like the ones in our vans? Cheers.
OK, firstly I must say that in my experience (40+ years), "Switch Cleaner" as we generally know it is very little help when it comes to "servicing" 12 Volt lighting (etc) switches. Most of the stuff you can buy (Servisol, Maplins etc) is NOT designed to do much at all to the relatively heavy contacts found in normal automotive switches. It is designed to "service" the likes of volume controls (etc) on Hi-Fi systems etc, where it cleans the delicate carbon track and coats it in lubricant that is especially geared towards carbon tracks and the associated brass "wiper". It can be effective in delicate multi-contact switches (as found in Hi-Fi etc) to a lesser extent.
When you consider what goes on inside a 12 Volt lighting switch though, one can see why it is of little use (imho). We have some fairly heavy duty lumps of brass that make a firm contact with each other via a spring. These contacts "arc" a little every time they are used, much like the rotor arm of a vehicles distributor. This arcing causes both erosion of the mating surfaces and a build up of pretty solid / crusty carbon deposits. In my opinion, no spray is going to do much to help rectify either of those two symptoms of a dodgy switch (of that type).
I have also personally seen Servisol virtually dissolve certain plastics (I once ruined the plastic jack plug sockets on a guitar foot peddle with the stuff), so I can't recommend that (other than for most volume potentiometers).
If I was going to spray something onto 12 Volt vehicle switches, it would likely be this = "DP60" on Ebay, but in reality, if I had a suspicion a switch needed attention, I would either strip it, clean the contacts by scraping them and lubricating the moving parts with a light application of Vaseline or simply replace it.
