Dashboard Switches

I have been trying to think of how I would like my dashboard to look.  I prefer a minimilistic look, but also keen on the period feel of the car.

I was going to use the Lucas toggle switches, one for lights, one for the rear fog and then a rotary one for the heater blower.  I did toy on the idea of having a swith that I could use to run my fuel pumps to be able to prime the system.

I felt that there were too many switches going to be present so I scoured the internet for inspiration.  

I really like the look of the original rotary knobs in the AC Cobra and I found a place on eBay that sold one for lights and one for the fan.  I had a rotary fan swith so the first job was to get the new knob to fit the switch.  The knob is designed to fit 1/4" hex shafts, but the 3 speed fan switch I have is round with a flat cut in it.  The rubberised knob that came with the switch has a steel insert in it.  I removed this and proceeded to get it to fit in the new knob.

Using the Proxxon, I machined out the internal hex of the knob until the steel insert fitted neatly.  I used some araldite to help bond the insert in.

For the light switch, I had one rotary switch which has 2 positions, side lights and main beam.  The full beam is controlled from the stalks.  That means I will still need another switch for the fog light.

I scoured the internet to see if I could find a switch that was easily modifiable which had the fog light function built in.  I came across a Mercedes light switch (MER-LSWT-004) which has the very functionality I need and looked like it could be modified for my needs.

I set to and dismantled the unit to figure out what I needed.  This unit has a LED in the centre of the shaft, so that was the first thing to be removed.  Looking at the shaft, I thought it easier if I took the shaft from the other switch I had (brass), machined the correct size of hex on it and fit it to the new knob.  I then modified the aluminium piece of the Mercedes light switch to fit the newly machined brass shaft.  I fixed it in using 2x roll pins.

Once that was done, the switch felt a little stiff to operate (new knob is relatively small), so I machined out some of the Mercedes switch internals to soften the "clicks".  I machined a small piece of black nylon to fill in the gap of the shaft to the threaded boss.

The switch now worked very well, pulling the siwtch to get the rear fog light to come on.  Once you switch the headlights off, the switch automatically retracts causing the fog light to go off.  

Black Nylon Insert

The last thing to do now was to make mounting nuts which hold the switches onto the dashboard.  Both switches had horrid looking hexagonal nuts, and typically were a completely a different thread and size to the Lucas nuts.  So I had to make some.

I turned a piece of stainless steel and created 2x blank pieces.  I made them the same diamater so they would look the same, although different inner diameters.  I worked out that the thread of the fan switch was 7/16" x 28 and the light switch was 5/8" x 24.  I ordered taps from the internet and once arrived cut the threads in my newly created nuts.  I then cut grooves in the nuts and also created a tool for tightening / slackening them.  I polished the nuts with the polisher - All in all a good job.

This way I will only have 2 switches on the dashboard and will have a period look.