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Well, I have adtually manufactured pots and think you can not do that.
Standard carbon track is made out of a 25mm or 16mm wide, 1 or 2 meter long pertinax (phenolic paper) strip, which is roller coated (for evenness and controlled thickness) with phenolic varnish containing various amounts of graphite dust which makes it conductive/resistive after drying and further baking in an oven.
Then you punch/cut suitable "omega letter" shaped tracks, add contacts at ends, attached by hollow or solid rivets.
Slider is an elastic piece of brass which **smoothly** slides over the delicate carbon track, without touching or even less going over the end rivets.
Any jump/bump will quickly make slider lose proper contact with delicate carbon track and make it useless.
1) you can not insert anything between carbon track and phenolic base the sameway you can insert nothing between, say, a car paint and stamped metal body, plus the "bump" will quickly destroy slider contact pressure.
Same with anything placed over the carbon track.
2) to improve contact at ends, pot manufacturer applies a tiny dot of "silver splash" , same phenolic varnish base as for carbon track but with silver dust in suspension, which also gets oven cured.
Layer is same thickness and strength as main carbon one so wiper can slide over it with no problems, but it must be applid while manufacturing, not later.
3) track taps are treated as "one extra end" so puncher uses a special die which leaves an "ear" where needed, which also gets its carbon surface and a little silver patch, to better contact an added riveted terminal.
Wiper never ever touches that rivet, it always slides along the main track.
4) mmmaaaayyyybbbeeee you can add an extra tiny contact (bent wire, brass strip, "catīs whisker" somewhere on a carbon track edge and where wioern does not btouch it, but itīs a most unreliable contact, no real melding of carbon + silver paint but just a tiny mechanical contact, poorly held ... what coud go wrong?
In a nutshell: it requires a factory custom made track, going through all the processes.
If you eventually will use thousands, you may custom order them.
For testing/prototypes use a many contact rotary switch (12/16/24/32) where you can build any custom "curve" and add as many taps as you wish, and only later commit to a cheaper regular pot.
Standard carbon track is made out of a 25mm or 16mm wide, 1 or 2 meter long pertinax (phenolic paper) strip, which is roller coated (for evenness and controlled thickness) with phenolic varnish containing various amounts of graphite dust which makes it conductive/resistive after drying and further baking in an oven.
Then you punch/cut suitable "omega letter" shaped tracks, add contacts at ends, attached by hollow or solid rivets.
Slider is an elastic piece of brass which **smoothly** slides over the delicate carbon track, without touching or even less going over the end rivets.
Any jump/bump will quickly make slider lose proper contact with delicate carbon track and make it useless.
1) you can not insert anything between carbon track and phenolic base the sameway you can insert nothing between, say, a car paint and stamped metal body, plus the "bump" will quickly destroy slider contact pressure.
Same with anything placed over the carbon track.
2) to improve contact at ends, pot manufacturer applies a tiny dot of "silver splash" , same phenolic varnish base as for carbon track but with silver dust in suspension, which also gets oven cured.
Layer is same thickness and strength as main carbon one so wiper can slide over it with no problems, but it must be applid while manufacturing, not later.
3) track taps are treated as "one extra end" so puncher uses a special die which leaves an "ear" where needed, which also gets its carbon surface and a little silver patch, to better contact an added riveted terminal.
Wiper never ever touches that rivet, it always slides along the main track.
4) mmmaaaayyyybbbeeee you can add an extra tiny contact (bent wire, brass strip, "catīs whisker" somewhere on a carbon track edge and where wioern does not btouch it, but itīs a most unreliable contact, no real melding of carbon + silver paint but just a tiny mechanical contact, poorly held ... what coud go wrong?
In a nutshell: it requires a factory custom made track, going through all the processes.
If you eventually will use thousands, you may custom order them.
For testing/prototypes use a many contact rotary switch (12/16/24/32) where you can build any custom "curve" and add as many taps as you wish, and only later commit to a cheaper regular pot.
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