I have the internal 24V SMPS from a printer, it's nice, IDK what the amperage might be, I'll check the mosfet as a guide.
So I wanted to make it variable so I used an LM317 and a 2N3055 circuit. So I was all happy to have it soldered up on a breadboard and then I realized I don't have the LM317 ref. pin on the OVERALL output, so of course it didn't work.
Its funny I never thought it through before I soldered it up wrong