[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Melting tar out of NSTs with a Weber (grill)-thanks

Original poster: "" <tesla@xxxxxxxxxxxxxx>

Hello All:

Regarding the asphalt potted NST's, I've found the best way is to soak it in a
container of gasoline, you'll need to daily remove the loose or dissolved
asphalt but it does the trick.  The next step is to completely disassemble and
clean the plates (I'm referring to an 'E' type Franceformer).  Then re-assemble
without 4 to 8 of the plates that go inside of the 'E' (the proper name for
those plates eludes me at this point).  I'm looking at one right now that came
out of a 15,000V, 60Ma Franceformer, it's measurements are:  7.25" X 1.25" X
Approx. 1/32" thick.

This increases the current through the xformer.  I would immerse the cleaned
xfrmr in oil and put 500pF bypass caps to each hi-voltage bushing, run to
ground (not your house ground, but an 8' ground rod).  Better yet is to use a
Terry Filter.

Also, from what I've heard, Franceformer has discontinued the production of
asphalt potted transformers, resorting to epoxy potting, which is anathemy to
our needs.


John & Scottie Cooper


Quoting Tesla list <tesla@xxxxxxxxxx>:

> Original poster: "Robert Hanford" <pomnept@xxxxxxxxxxx>
> Thanks for the replies. The butane torch idea is interesting, would propane
> work as well or is it too hot or not hot enough?
> Robert
> Depending on what you are trying to remove the tar from a butane
> torch is the best bet. Just pass the torch back and forth and let the
> tar run out. Watch road crews as they use torches to preheat road surfaces.
> You have to remember that tar is made with petroleum and confining it
> in an oven you could get enough out gassing to create explosive
> atmosphere in the oven.
> Using a grill can do like an oven - the tar will out gas and the
> vapors can be ignited by the grill.
> Hope this helps
> Al Shumate