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Default Nichrome winding insulation question

msg wrote:

WKW wrote:

I have two old soldering stations with burned out elements I want to
rewind. ( One is an old ungar they quit making ages ago but it was a
good iron ) I found some #30 Nikrothal 80-20 wire cheap on eBay which
appears to be the same length and resistance as the original. I just
want to know what kind of paint or insulating material to use to keep
the wire from shorting to the metal barrel or to neighboring turns (
They are both 24 volt transformer units ). I took one elemant apart
already and the coil is sandwiched between to metal tubes about .02"
apart.



I am sure that you will receive replies from folks considerably more
familiar
with heater construction than myself, but FWIW, please see how I worked
with
soldering iron heaters to build an SMT hot air rework tool at:

http://www.cybertheque.org/homebrew/smt-rework-tool

I found that windings separated by ceramic spacers was typical in units
that I disassembled and I used refractory cement in my finished unit to
provide structural strength and thermal conductivity and thermal insulation
in appropriate places.


I forgot to mention that the internal insulation in all of the heaters I
cannibalized was mica -- in discs, sheets, bars, etc. Ceramics made up the
rest of the structural material. When inserted into the metal tube, the
spacers prevented any contact with heater wire.

Michael

Michael