Tesla coil first attempt?

What kind of transformer is it, designed for a neon sign? If so, the secondary winding is probably center tapped and the tap is grounded to the case - DANGEROUS in this circuit if I understand you correctly!!! 35 mA is the current rating: 35 Mili Amps or .035 Amp. You can wind the primary on any non-conductive material. The ones you mentioned would all work, though wood wouldn't be the best choice. TUNE a Tesla coil? The only tuning I am aware of would be of an R.F. oscillator, which you are not using. I have never played/worked with a Tesla coil, but have seen a number of them in operation and examined the construction. I have never heard of one using 60 Hz in the primary - the ones I've seen all used a radio frequency (RF) oscillator for excitation. But if you are trying to feed 4 kV into 6 turns of # 10 wire, I'd say you will either blow a fuse or "tune for maximum smoke" - probably the H.V. transformer! That capacitor in the transformer primary needs to be rated at no less than 670 Volts, (1.4 * 240 * 2) for a safety factor. I would recommend a bleeder of about 1 Megohm and 1 Watt, though it shouldn't be necessary except for safety after you unplug the unit. Good luck with the project!

4000 VOLT 35MA CAN KILL YOU INSTANTLY WITHOUT EVEN TOUCHING THE TERMINAL WITHIN ONE INCH AREA. YOU HAVE NO EXPERIMENT AND TOOL TO HANDLE HIGH VOLTAGE. THIS IS NOT A GOOD CIRCUIT TO PLAY WITH. INSTEAD,USING TV FLYBACK TRANSFORMER HAS CURRENT LIMITS TO 0.5MA.THAT IS MUCH SAVER TO PLAY.

I had a neon sign transformer like that and only energized it once. I decided it was much too dangerous. I don't think mine had a center tap connected to the case, but maybe I did not check. I put a 120 volt 75 watt incandescent in series with the primary and connected it to the 120 volt utility. The bulb lit dimly but it brightened when I drew an arc. Apparently the no load voltage was several times the the name plate voltage, and the arc easily ignited a long strip of paper. A 22 inch torid, with aluminum inside, does not seem correct ,if that is your primary coil. Perhaps the toroid has a different use? You cannot connect the transformer directly to the primary. You need an arc to chop the 60 hertz into a higher frequency. This design of tesla coil is an RF noise generator and is likely illegal, so operate it rarely and briefly or you may get complaints from as far away as a mile. It is a 100 watt spark gap transmitter without an antenna. 1 several 400 volt capacitors in series should work well. 2 I suggest a 2 watt resistor with millions of ohms resistance, shunting each 400 volt capacitor. More ohms means the capacitors may be dangerous for a few more seconds after shut down. 1/4 watt resistors may be ok. 3 Possibly you need 2 each 120 volt light bulbs in series with the primary, since you will operating on 220 volts or possibly 240 volts. More likely one bulb is fine if it is rated 150 watts or more. You should do your initial testing at 120 volts to reduce the smoke and electrocution hazard. You tesla coil will likely work with as little as 30 volt input, except the arc may be too small to be reliable. A 2.5 milihenry choke or there abouts will likely reduce the radio noise. One in each power line lead. 4 I suggest not using wood. 5 You can draw an arc from the secondary, almost as long as possible. The arc will brighten as you improve the tuning. Please be careful, the primary voltage is likely more dangerous than the secondary voltage and your transformer can kill you. Neil

I had a neon sign transformer like that and only energized it once. I decided it was much too dangerous. I don't think mine had a center tap connected to the case, but maybe I did not check. I put a 120 volt 75 watt incandescent in series with the primary and connected it to the 120 volt utility. The bulb lit dimly but it brightened when I drew an arc. Apparently the no load voltage was several times the the name plate voltage, and the arc easily ignited a long strip of paper. A 22 inch torid, with aluminum inside, does not seem correct ,if that is your primary coil. Perhaps the toroid has a different use? You cannot connect the transformer directly to the primary. You need an arc to chop the 60 hertz into a higher frequency. This design of tesla coil is an RF noise generator and is likely illegal, so operate it rarely and briefly or you may get complaints from as far away as a mile. It is a 100 watt spark gap transmitter without an antenna. 1 several 400 volt capacitors in series should work well. 2 I suggest a 2 watt resistor with millions of ohms resistance, shunting each 400 volt capacitor. More ohms means the capacitors may be dangerous for a few more seconds after shut down. 1/4 watt resistors may be ok. 3 Possibly you need 2 each 120 volt light bulbs in series with the primary, since you will operating on 220 volts or possibly 240 volts. More likely one bulb is fine if it is rated 150 watts or more. You should do your initial testing at 120 volts to reduce the smoke and electrocution hazard. You tesla coil will likely work with as little as 30 volt input, except the arc may be too small to be reliable. A 2.5 milihenry choke or there abouts will likely reduce the radio noise. One in each power line lead. 4 I suggest not using wood. 5 You can draw an arc from the secondary, almost as long as possible. The arc will brighten as you improve the tuning. Please be careful, the primary voltage is likely more dangerous than the secondary voltage and your transformer can kill you. Neil

4000 VOLT 35MA CAN KILL YOU INSTANTLY WITHOUT EVEN TOUCHING THE TERMINAL WITHIN ONE INCH AREA. YOU HAVE NO EXPERIMENT AND TOOL TO HANDLE HIGH VOLTAGE. THIS IS NOT A GOOD CIRCUIT TO PLAY WITH. INSTEAD,USING TV FLYBACK TRANSFORMER HAS CURRENT LIMITS TO 0.5MA.THAT IS MUCH SAVER TO PLAY.