On Thu, 07 Apr 2005 21:41:05 -0000, the renowned
(Dave Platt) wrote:

Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

A cautionary note - if it's that critical, then re-using wire which
has alread been wound might not be the best idea. You'd be starting
with wire which had already been bent/flexed, and if you aren't
careful this might put some kinks or irregularities in the winding of
your new coil which might affect its impedance or Q.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

You might be able to do it with a vernier caliper.

24 gauge has a diameter of .511 mm or .0020"

30 gauge has a diameter of .255 mm or .001"

Ooops, you're low by a factor of 10:1 in the inch calculations. Just
as well, since a caliper is hardly repeatable to 1 thou, let alone
measuring a diameter of that size with any accuracy.

Every 3 gauge numbers corresponds to a 2:1 ratio in wire area (amount
of copper). Every 6 gauge numbers corresponds to a 2:1 ratio in wire
diameter.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com