In light of reading some suggestions on how to “Band-Aid fix” a dash dimmer switch or some offerings of a “rebuilt” dash dimmer switch, I put together a few videos and some pictures. This addresses only one aspect in hopes that it will deter the usage of epoxy for re-installing old scorched resistor coils back into their porcelain mounting trays.
Did you ever finish driving your car and for some reason had to open the hood and touch the ballast resistor on the firewall? Feels good, doesn’t it!
The same thing can happen with a dash dimmer switch. If the switch is working properly or restored correctly, there will be no resistance in the full on position. No heat is occurring because there is nothing in the way of holding back any current. When the dimming effect of using resistance the switch was designed for comes into play by turning the dial counter-clockwise or due to corrosion, heat builds up. It’s just simple physics.
I made four short videos that tell the story better than me.
The first up is an original unrestored E body dash dimmer switch that has one of the typical problems not working in the full on position, but turning the dial counter-clockwise slightly to get some light output. Nothing special used, just a car battery driving this dimmer with a headlight bulb as a light source instead of a string of bulbs in parallel.
The second video shows a dried piece of epoxy touching the resistor coil. It is about a minute long, but half way through, you can see the epoxy melting until falling off. No problem fast forwarding if you don’t like to watch paint dry or grass grow.
The third video is picking up the piece that melted off due to heat showing the burn marks.
The fourth video speaks for itself.
Before I started to offer my version of a “restored”, not just a "rebuilt", dash dimmer switch, I asked myself this question. “Is there any possibility of this switch catching on fire?” Epoxy wasn’t even an option to test.
Yes, I am a hoarder. I saved the very piece of wood I used along with a propane torch to see if I could possibly catch what I use to install my new custom made 302 stainless steel resistor coils on fire. The answer was and still is no. However, I did catch the wood on fire!
Sorry, I don’t kiss and tell, so please don’t ask what I use or how I do it. Be assured that a JS Restoration will have either version of B body thumbwheel dash dimmer switch and the E body dash dimmer switch each fitted with replacement 302 stainless steel resistor coils (Made in the USA) working like new, producing the light output the factory intended with the correct bulbs specified in their service manual.
Thank you for reading and watching these videos and looking at the pictures. If only one car can be saved from any possible damage, it was worth posting.