02 August 2014

How to cut potentiometer shaft

I have always been very bad at finishing my projects with a proper enclosure. But something meant to stay like a CW keyer needs a good home. That's the case of my reproduction of the excellent K3NG Arduino keyer. The main challenge for me is drilling holes, and the keyer needs at least 6. I had an unused L-C tuner and its box was pre-drilled too!

When everything was almost inside I noticed something I had forgot: the long pot shaft! The knob on the very top doesn't look too nice, does it?!


No way I would take everything apart, and a quick web search revealed few methods to cut it out. The simplest solution was to use a pipe cutter: no electric tool! I passed over the requirement for a vice, crossed my fingers and started turning around:


At this point I held the lower part with pliers and snapped away the top length of plastic:


The final result is nice and I have a CW speed potentiometer, that is much more practical and immediate than "tap here n'there" methods.

Then another problem arose: the 3.5mm panel plug is too short for the box thickness and I cannot put the nut on!