2A Variac for Phase Shifting

Last week I took delivery of the first item needed to create the phase shift module. I was going to rely on mechanical adjustment for phase shifting but after a lot of reading up I have decided that the ability to adjust phase remotely while the tesla is operational is a must. If you are pretty new to Tesla coil building (like me) the subject of phase shifting can sound quite complicated. In simple terms, the synchronous motor rotation is locked to the sine wave of the AC power supply meaning that the spark gaps always present themselves at the same point on the sine wave. Without any phase shift the same AC sine wave is applied across the capacitors meaning that the spark gap may not present as full charge is reached in the capacitors. Phase shifting allows you to advance/retard the sine wave to the synchronous motor so you can present the gaps when full charge occurs in the capacitors. Without phase shifting you can only alter this timing by physically rotating the motor in its mount or rotating the spark gap disc relative to the motor shaft. Both of these being impossible (or very dangerous) to do while the TC is in operation and can be very difficult to quantify adjustments.
To make the phase shifter we use a variac wired as a variable inductor, a motor run capacitor and bleed resistor.

First to arrive was a 2A panel mount variac. I bought it from a seller on eBay called Wattbits. This is the second variac I have bought from these guys, the first was a 10A version that is the main power source for the Tesla coil.

Here's the 10A version in the power supply module.

The 2A version is physically about half the size. I want the phase adjust module to look similar in design to the power supply module so I have ordered a length of 185mm diameter clear acrylic tubing and a couple of 185mm acrylic discs for the top and base.

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