On 10/15/19 12:32 PM, John Robertson wrote:


Perhaps mineral spirits - sometimes called Varsol if I am not mistaken -
will do the job.

https://www.wisegeek.com/what-are-mineral-spirits.htm

Is there a problem with coating the parts in wax even if they are still
coated in some residual oil? I expect the reason for the paraffin was to
waterproof the parts and as paraffin is just another form of oil would
it now work just fine all be it somewhat discoloured if the oil residue
dissolves into it? It just won't look as nice...

John :-#)#

Interesting question. True about paraffin and oil relationship. Didn't
think of that. Well, it was my project. The high voltage transformer
was submerged in about 64 oz of mineral oil. It was in a pvc junction
box and stayed in there for years. Connections into the box were single
hole and single wire, then sealed by RTV or epoxy. Interestingly, it
wasn't my seals that leaked. Somehow, the oil seeped into screw holes
on the bottom of the PVC box and leaked down into another storage bin
I've had the entire thing in just for that purpose in case it ever
leaked. I never trust oil filled electronic devices. I used to work on
dental x-ray units, which are (were) all metal housings and even vacuum
sealed. However, more often that not, even perfect ones in storage
would end up with an ounce of oil under them after being stored for
years. However, that was a tried and true business, never had to remove
oil from anything and if the transformer was bad, it was just junked.
Here, with my own project, is obviously a different story if I am going
to pot the coil in the paraffin. I think I'm going to pick up a couple
of cans of electronic component spray cleaner, which doesn't leave a
residue, and spray out the transformer and PVC junction box insides as
much as I can, let dry, and then refill with the molten paraffin. I'd
like to leave the assembly in the oven for a while to make sure as much
air works out as possible, but my oven has a minimal of 170 F. It might
be too much, but I'm not sure.