
I have just installed the engravity toggle caps which are originally intended to use on 3mm shaft. Since all my switches are 6mm shaft, I wanted to install these without a mess of glue.
First I attached the aluminium pieces in a lathe, and drilled a 6mm hole. I used a piece of tape on the bore, so each piece would get the same lenght of the hole. You want to use a lathe for drilling this hole bigger, since the aluminium walls only will be 0,5mm thick after this process. No hand drilling


Then I installed shrink tube and heated it around the knob shaft. Some experimentation needed to find the right "spot" on the shaft.

Then grab the shrinked shrink tube with a plier, and start screw the aluminium piece into the shaft. Some force is required. If it go too easy into place, you might need to install the shrink tube again, a little closer to the shafts end.

If you got your shrink tube in the correct location, the aluminium piece get really stuck. And without the mess of using glue.

Use a knife to remove the rest of the shrink tube that is visible

And the result is a much more realistic overhead

