Step 2: Parts
• Flyback transformer
Newer flybacks are recommended as they are very robust. You can use an older flyback for higher current output, however, they are more likely to burn out due to excessive voltage.
• 2x 470Ω 2W resistors
The color code is yellow/purple/brown
• 2x 10KΩ 1/4W resistors
The color code is orange/brown/black
• 2x 12v 1/4W zener diodes
• 2x 400+ volts fast diodes
I used UF4007 diodes.
• 1x inductor
The value is not critical but it should be 47uH to 200uH rated at 10A or more. You can find an inductor from a computer PSU or you can simply make your own, just wrap 20 turns of 16 gauge of enameled wire around a ferrite toroid.
• 1x 0.68uF 250v (or higher) capacitor
This capacitor must be bipolar and must be good quality, such as MKP ot MMC types. NEVER use an electrolytic capacitor, they will blow up. You can test various types of capacitors to see which one suits your ZVS driver well.
• 2x IRFP250 MOSFET's
They are a bit pricey, however, you can use other MOSFET's that has Vds 4x more than the power supply and has the Rds(on) lower than 150mΩ. Unfortunately those MOSFET's are a bit over my budget so I used the IRFP254 MOSFET's instead, not the best, but it is cheaper and it and it should give me good arc results. I also tried using the popular IRF540 MOSFET, however, it gave me very poor results.
• 2x small heatsink
They won't be necessary if you are going to run your ZVS driver lower than 12v.
• Large variable voltage power supply
Now this can cost quite a big chunk of change, you can a computer power supply unit for 12v power source. If you want a higher voltage power supply, then you might want to consider modifying a microwave oven transformer, but this is another project. As I don't have a large power supply so I used six 6v sealed lead acid batteries all in series to gain 36v to power my ZVS driver.
Then finaly the other bits and pieces you may need such as solder, thick wires, etc.