It was an old post on Lena’s guestbook: Lena's guestbook / Гостевая книга Лены
There’s also various other posts including on this forum:
https://www.geocities.ws/hairfreethere/
It’s very simple to build one of these devices. A 9V battery would work, but I like the 12V so it’s capable of higher currents. I wouldn’t go too much higher without a good current limiting circuitry. Usual potentiometer is a 11kΩ for 9V, and around 20kΩ works ok for 12V. Mine was salvaged from an old radio. The foot pedal is from aliexpress. The wires are flexible 20awg silicone wire, from hobbyking or aliexpress. There are a lot of digital or analogue ammeters (1-2ma range) on aliexpress that could be used instead of a multimeter. A Ballet Prima Ejector needle holder would be nice and they usually come with a banana socket. Hobbyking has good quality banana plugs and sockets. Using a probe holder with built in switch like some of the Sterex ones instead of the foot pedal might be more convenient for a lot of areas when doing electrolysis on yourself.
I’d do a lot of research first. Make sure you understand the basic concepts like ohms law (current = voltage / resistance), how to calculate units of lye. 0.1mA * 10s = 1mC (millicoulomb) = 10 UL (Units of Lye).
I haven’t read the whole thing, but this seems like a good basic overview:
This is a very good resource, the Hinkel lectures on “Balancing the Currents” and “Tips on Inserting an Electrology Needle” are a good start.
https://electrologynow.com/
The various pages on this site are all a good read, although some may be a little controversial here.