Look at the back. There should be a 3/8" hole in the center.

Loosen the three black screws (only one shows in the photo, to
the right of the lock tab). The counter will lift off. Then you should
be able to lift the knob free of the back. You will find room in the
back of the knob to accommodate the 3/8" diameter mounting bushing of a
potentiometer, a flat washer, and a thin nut -- the kind normally used
for mounting pots and rotary switches on old electronic equipment.

Now -- in the back of the knob should be a 1/4" hole, and there
should be two setscrews at the back of the knob (probably hidden by the
skirt) which can be tightened by a long skinny Allen wrench to lock the
knob onto the 1/4" shaft of the potentiometer.


I was wondering what those holes were for, they can be seen in picture
number 4 he

http://counterpot.blogspot.com/

where I have a few photos of it disassembled. Thanks for the post, I
thought it was just a hand counter for use around the office but now I see
how it can be attached to a shaft.



When the knob is mounted on the shaft, turn it fully CCW. Reach
into the back of the counter mechanism, and turn the gear there until
the counter reaches zero, slide it back onto the base with the screws
passing into the slots in the skirt, and tighten the screws. At this
point, your knob should read "000" with the pot fully CCW, and some
value when the pot (it should be a 10-turn one) fully CW. Ideally, it
should read "999", but based on your counting the turns vs digits, it
probably won't. (Unless you were determining a full turn by a visible
hole for a setscrew, and missed the fact that there are two at about 90
degrees separation in the knob.

I *have* used this kind of knob, though more recently I have
mostly used the more shallow versions which I described in my last
quoted paragraph above. IIRC, the photographed style, I last saw in
*new* use around 1960, used to build things like temperature controllers
for test ovens for semiconductors which had to meet tight specs.

If you have no future need for it once the contest is over, I
might be interested in acquiring it from you. I have not seen that
style for a long time.


On the bottom of the silver dial is written "Borg Equipment Division,
Janesville Wis. USA, The George W. Borg Corporation".

If you would like to have it I'd be happy to send it to you, email me and
we'll work out the details.


Rob