Build 67. Tunnel Top with Heated Seat Switches
I went for heated seats for my build and although most of the wiring loom is already pre installed for it, I am still required to cut the holes in the tunnel top for the switches to fit. I emailed CC when the kit was delivered to ask about how they do this in the factory as the tunnel top (with carbon vinyl) is an expensive part so I didn't want to mess it up!
They sent me a pdf jig (downloadable below!) that they use in the factory (basically an A4 sized scanned drawing) which marks where to cut the holes. I used this to mark the initial holes on the outside and then used a tape measure to get the exact centre point on each side. Next I drilled a 2mm hole in the exact locations to mark the pilot hole, (N.B. I drilled from the inside, metal first)
The factory uses a 16mm Q Max cutter (as shown in the images) to cut the initial hole in the fabric and the aluminium. To use this cutter I needed to widen the initial hole to 8mm for the bolt to go through, I did this in steps of 2mm widening it slowly to keep it in the middle, drilling from the aluminium side first (trying not to touch the fabric part too much). Then I used the Q Max cutter on both the holes to get a nice 16mm hole in the fabric and aluminium.
Once this is done you need to file the aluminium holes (only the aluminium parts!) to 20mm whilst not touching the fabric part (leaving that at 16mm). This means that when the switch slots in, the fabric is held nice and taught and it will all look professional!
To widen the hole I drew around a 20mm socket with permanent marker on the inside and then I used a Dremel with a drill bit attachment to widen it to the markings. The drill was barely put into the hole to ensure it did not catch the fabric (there is plenty of space as the fabric sits about 8mm beneath the aluminium because of the cushioning). It was also necessary to put a small notch in the side to stop the switch from spinning. I also used a grinding stone to smooth the hole off once it was the right size.
I have to admit I spent a lot of hours pondering on this and worrying about messing it up, but in the end it was fairly trivial, just so long as you measure lots and then take your time widening the aluminium hole! I'm very happy with the result, even my wife said it looks professional!
The last job was to place the tunnel into the car, I tucked the seat heater wires well into the scuttle area (above the padding) and also tidied them with cable ties. The handbrake was pulled to it's highest to allow it to slot into the hole. I then used a plastic trim lever to ensure that it placed over the carpet and then pushed it into position. I decided not to screw it into place as it was quite snug anyway and the seats will also hold it in place some more.
Timelapse
