This 8 electrode pair, series quenching rotary synchronous gap was used for all my sync gap TC work from 1" to 65" spark output. The electrodes are positioned in two clusters such that the electrodes line up only twice during each revolution. This gives the typical 120 BPS of a sync gap, yet forces the arc to snake its way through 8 series gaps during each firing for better quenching. The motor is a 3600 rpm modified induction motor rated at 1/10th HP. The motor can be rotated in its cradle to adjust the sync-phase. The rotor is made of lexan, the electrodes are steel, and the framework is a wooden assembly.