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What types of oil can be used for high voltage transformer insulation? Answered

I am modifying microwave transformers for a higher voltage to drive a Tesla coil and I need to know what kind of oils for example vegetable or paraffin can be used for high voltage insulation in the transformer to protect it?
To what voltage will it insulate?


You can start out with putting your question into a search and get lots of hits. I think you are looking for some kind of mineral oil, one that does not break down easily and is non-flammable.

yup, most diy hv enthusiasts either use:
transformer oil
some sort of tar
mineral oil (works great and easy to get)

just make sure u get rid of air bubbles in the liquid

it may work, but that just sounds like a bad idea, I mean paraffin oil is kerosene, right? Dunking high voltage stuff in a highly flammable liquid in hopes the liquid causes the high voltage equipment to stop arcing is just a bad idea :P

Have you ever tried lighting it ?
liquid kerosene is used in EDM machines sometimes as the working fluid - and even when you kick whacking great sparks under it, there is no fire.


I just tested my paraffin oil, it's food grade and I couldn't ignite it.
One of my main concerns is that the oil wont be able to make its way through the windings.

I woudnt use a MOT for that. They are pretty weak for a tesla coil. Use a DC flyback. But you could use mineral oil or vegetable oil though..