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"

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.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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