Tesla Coil

Spark Gap

Here is my multi-segmented spark gap for my 2.375" coil. It has just been modified by cuting the electrods to
a shorter length. It has a total of 3 gaps I will explain more below.

These pictures are in 640x480 pixles resolution for a higher resolution click on the pic.

This is a picture of my newly modified spark gap. The electrodes used to be 3 inches long,
now they are 2 inces long. Cooling and quenching is provided by a 3 inch fan. The air flows
between the 3 gaps out through the back.

Here you may see that the gaps are easily adjusted and may be move around for a bigger gap size.
The gap is set at 0.192" each gap is 0.064". I have milled groves for the airflow
between the electrodes and for the bolts to move the gaps.

The electrodes are made from a copper pipe that was cut in to 3" segments and are 1.125" in diameter,
but following some advice from the Tesla Mailing list I cut them down to 2.125". They are held
in place by aluminum C Channel, it is 0.875" wide, 2" long and 0.5" tall, this also helps with
cooling the gaps. I have used the previous version of this spark gap and worked very
well. This is also a great deal quieter than previous gaps that were used before
because this one is enclosed in plastic.

email me at
if you have any question or any tips.
last updated 09/28/02

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