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[email protected] tabbypurr@gmail.com is offline
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Default How do they paint the stripes on resistors, bumble bee caps, etc?

On Wednesday, 3 January 2018 16:11:52 UTC, Clive Arthur wrote:
On 09/09/2017 03:11, wrote:
I've always wondered how they paint on the colored stripes. I put "how
do they paint the stripes on resistors" on google, but all I got was
links explaining how to READ color codes.

Has anyone ever heard anything about this process?


Resistors are made from a clay-like material containing carbon or other
conductor in various amounts. Colourants are added, and the material is
rolled and layered into large 'pats', so for example a 4k7 resistor pat
might have cream, yellow, cream, violet, cream, red, cream, gold, cream
coloured layers. This is rolled to the correct thickness corresponding
to the final resistor length, then hollow punches form the resistor
bodies, usually several thousand from one pat. The better quality ones
are rolled for smoothness and low noise. The wire ends are fitted, the
resistors are baked and often varnished. For high accuracy resistors,
the depth of one wire end is adjusted on test before the baking stage.

Cheers


You're surely pulling someone's leg.


NT