This standard screwdriver seems to be repelling a spark despite it being metal.
“Continue reading” for more details and photos.
It is interesting how the arc bends around it.  This is because the hot arc channel is a low resistance but the air just next to the screwdriver is cold (or at least not not ionised and would have to be “jumped” by a sufficient voltage for it to connect. This only happens with stable pulsed DC or AC arcs.  One could make up a bit of a pseudo-explanation for the arc repellent screwdriver and indeed I have on the 4HV community.

Of course it does spark to the metal as expected if it is close enough.

The air around the screwdriver next to the metal remains cold and presents a greater barrier to the spark jumping across it than to continue to be conducted in the spark channel. This only occurs once the spark is established as it becomes of lower resistance and lower voltage.
When a high voltage (say 10,000 V) strikes initially, it will tend to take the shortest path and would have jumped on to the screwdriver then “out” of the screwdriver and on to the other electrode saving a few mm in total path (=thickness of the screwdriver).
Here though, the arc was established in air without the nearby screwdriver.
Once a high voltage arc is established with a current limited supply then a constant current flows through the ionised channel. A soft orangeish spark forms. (different to the very brief but brighter lightning or Tesla coil sparks) This spark channel will have a much lower voltage across it and the 10,000 V will drop to say 1,000 V or less. Similar to a fluorescent tube which needs a starter pulse of high voltage

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External links

Arc Repellent screwdriver Google+ post:  Jul 29, 2011. 15 comments

Photo Date: Oct 1st, 2004