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Peter W. Peter W. is offline
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Default making wires on circuit board immobile but able to be removed later?

Arie
I would think that candle wax would have dyes and perfumes added. Lots of coils, capacitors, transformers, etc. were potted in wax for decades without issues. I guess pure beeswax would be the safe bet though.


Carnauba wax (plant-based) Beeswax and Paraffin wax all have their negatives.
Carnauba wax and Beeswax are both highly acidic, albeit with 'weak' acids - but will attack bare copper and untinned copper wire over time. You will note that old waxed-paper caps used tinned copper or iron leads, not bare copper. You will also notice than when wax 'leaked' onto the chassis, there would be a permanent stain on the chassis - from the acids in the wax. The mix on the old paper caps and coils was, typically, 80/20 paraffin to beeswax - the admixture was more stabile than either alone, and easier to work than either alone.
Paraffin wax oxidizes, is highly flammable - more so even than beeswax- and while hydrophobic is sufficiently lipophilic as to attract fat-based contaminants out of the air - such as cooking odors, nicotine and so forth.

Transformers back in the day were 'potted' in either an asphalt-based tar (equivalent to modern non-plasticized hot roofing tar - that which is melted in tar-wagons), or in coal-tar pitch (awful stuff!). Both of which are stabile over a wide temperature range. Some few things were, in fact, potted in wax, but today that wax would be called "Jeweler's Wax) which, when cold is machinable and quite hard.

There are 'archival' waxes that are both acid free and self-extinguishing, but at $8 - $15 per ounce, not cheap.

I keep archival glue-sticks, electronics-safe glue sticks (compatible) and conventional glue-sticks (not compatible). I need two glue-guns as the change-over is quite wasteful otherwise.

Peter Wieck
Melrose Park, PA