@Smoke7, I may be paranoid, but I would not use copper wire to attach the silver bar. Especially if you are using heat, I think there could be moisture that would get on the copper wire, complete the circuit, and suck some copper into the electrolysis. It might be worth the investment to get some silver wire.
The basic instructions call for cleaning the electrode at the end of the process. That is fine for making a liter of 20ppm. If you start make higher ppm with heat & gelatin, you will need to fire clean the bar along the way, perhaps several times. For example, when making a liter of 320ppm at 15mA, I clean the anode (& wipe the cathode) about every 20 minutes at the beginning. Toward the end, it seems like I can extend the time to 30-35 minutes. I also find that I get less build up of silver oxide on the cathode when I run with the water hotter.
The SH-2 on eBay or Amazon is an economical stirring hot plate. I see Amazon has an even cheaper stirring hot plate available now, but I don't know anything about that one. I've used an SH-2 for several years.