My first time soldering the high voltage multiplier circuit was an annoying experience - but in the end its a good lesson learned after the fixed. The mistakes was to solder the capacitors close to one another resulting in the high voltage to stray out and short circuit in between the capacitors pins. I thought that using candle wax to prevent the straying voltage but it simply didn't work. Finally scratching out the nearest conductive electrical path is the solution - by doing this, it widen the gap in between the pin and prevent it to stray out to another pins. Hectic works but valuable lesson learned. In future place the capacitor in reasonable distance between one another to prevent this to happen again.
10 Nano Farad or 0.001 Microfarads is good to make voltage multiplier