I've got a secondary coil for a tesla coil and would like to spray it with some lacquer I got at my local hardware store. Is this kind of lacquer okay?

Do it Best
Do it Best 11 Oz. Clear High Gloss Spray Lacquer

 

The important things about what get applied to the coil are first, that it does not damage the insulation of the coil wire, and second, that the coating does not contain any conductive material, such as carbon particles or metal particles. That should be verified by looking at the label on the can.

 

Are any of these bad?

ACETONE, LIQUIFIED PETROLEUM GAS, n-BUTYL ACETATE, GLYCOL ETHERS and AROMATIC HYDROCARBONS.

 

lacquer not a good pick this is betterKrylon Kamar Varnish,

 

Welcome to AAC.

The problem with ordinary spray coatings are breakdown voltage and resistivity. Something like MG Chemical‘s acrylic conformal coating is designed to be high voltage compatible and is even specified for preventing arcing. It has a rated breakdown voltage of >1500V and a resistivity of 4.6 × 10¹⁴Ω-cm. A similar product is Tech Spray FINE-L-KOTE AR.

Any product not designed for this may or may not have similar properties and because they are not made for it the manufacturers don’t test for or report it (that I can find). Based on the chemistry it is reasonable to make the assumption it is likely they offer about half these specs.

The other potential problem is hydroscopic behavior. Coatings will vary in their tendency to absorb ambient moisture. If they are formulated in a way that makes this aggressive, the conductive water will reduce the high voltage handling capacity.

 

A very good point is made about moisture absorbing!

 

Thank you all, your input is appreciated.

 

Remember that 555 timer circuit that is supposed to tell me the resonant frequency of a secondary coil? Well, in the video it shows on the schematic that there is a ground connection. I've discovered that if I connect the potentiometer to my body with a wire, or to the house's ground connection through my variable power supply, or just by touching the battery with my hand, I can get different readings. Do I really need a ground connection? If so, how do I properly ground it to get the right reading?

 

Whoops. I just realized I put this question on the wrong thread.