Variable capacitors of small capacity.
(I did not find a topic about old components for theremin here).
I am publishing a photo report of my experience.
This is an extinct type of electronic elements. Previously, there were these:
convenient for fastening to the front panels of devices. With a shaft for the handle. I managed to get suitable ones, with fastening for a nut, but without a shaft for fastening the handle. For a screwdriver. I went for broke, forgetting decency)) When the head says - no way! This will be rude and ugly! And the hands say - Ah!! Spit! somehow we will break through! I took old steel sewing needles, stuck them tightly into the groove of the short shaft, on epoxy glue. Then I put a thick spring on them, suitable for the diameter, also on epoxy glue. It seems to have turned out to be a strong shaft. And along with these experiments I decided to use epoxy glue to install the shaft on regular trimmer capacitors. Trying to ensure the maximum area of gluing, contact of the shaft with the capacitor.. Also, using advertising plastic, which is very easy to process (easy to cut with a knife, glued with super glue), I made shafts for those capacitors that were extracted from radio equipment of the 80s...90s. (In some video recorders, for example, there were miniature variable capacitors, 5-10 picofarads. And all this, wholesale, and did))
I didn't guess with the diameter of the shaft under the handle. Then I tried to wind a thread there, on universal glue. Thicken. But it didn't turn out very well. And in this case, you also need to use epoxy glue.
In some models of theremins, the capacity of such variable capacitors turned out to be large, and I used a dremel to cut out part of the metal plates of the variable capacitors, reducing the capacity.
What happened:
