Interesting experiment 🙂
I think I am spoiled because I once had the possibility of actual access to the Pot factory.
Which like many other mystery things in Life, is not *that* magical after you actually see it.
80% of the process is metallurgical/mechanical, such as stamping, turning, punching, bending the pot cases and other sheet metal parts (old style pots that is), rivets and riveting, terminals, wipers, etc.
Only injected plastic parts were shafts in various shapes (long/short/ribbed/split/D type) and the real pot parts were tracks.
They cut long, narrow (pot diameter width , either 16mm or 25mm) "Pertinax" (phenolic paper matrial) strips, and applied, with metal rollers, some "Resistive paint" , in various degrees/concentration which they sourced from Philips Holland.
Basically finely ground Graphite floating in a Phenolic Varnish solution.
There were various cans; one good for, say, tracks from 50k to 200k , and so on, higher and lower.
So a single uniform layer, full width , would yield, say, 100k Lin tracks.
Faster or slower speed gave you thinner (up to 200k) or thicker (down to 50k) tracks.
For other values, you used a different conductive paint.
Then the strips were cooked in a controlled temperature oven, which allowed for finer resistance value tuning, pots were very good quality and very consistent.
Then the Omega shaped tracks were punched out of the treated strip, holes punched and pot was assembled, basically by riveting.
Log pots were made with, say, a 200k full width coat and a superimposed 10k half layer one.
Antilog were exactly the same original strip, only punched "upside down" , and my custom S taper just a log strip punched sideways (turned 90 degrees) so resistivity when assembled was low-high-low .
As you see, not that big deal ... if you have access to a small factory and the owners.
That is an unseen area we lost with "globalization".... now parts factories are few and monster size and it's impossible to get custom/special parts unless you are a BIG customer.
The part in bold - with suitable values it would work just as well as a high value pot. Getting a suitable value linear pot 'might' be a problem, but that doesn't invalidate the principle.
Yes a shame 🙁
At one time you could easily make your own custom pots, as all the parts were freely available and simply slid together - but those are long since vanished as well.
It wasn't cheap, but it was a VERY handy way to build a replacement pot when you couldn't get the original one any more.
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