Radio Shack has an example of generally fine wound wire on
coil forms.  Its their #278-13458, which is an assortment of 3
enamel coated magnet wire.  The package I have uses this
side-by-side wire wound method, but its really machine wound.

One coil uses 40 ft (12.2m) of 22 gauge wire (~.7 ohms).
One coil uses 75 ft (22.8m) of 26 gauge wire (~3.3 ohms).
One coil uses 200 ft (60.9m) of 30 gauge wire (~22.6 ohms).

The coil forms are some form of white plastic, about .088"
to .1" thick; which don't seem to deform or vary on the inside
diameter very much ~ .803 to .807".  The thought of using a
3/4" (.750") magnet or pole inside has occurred, as a possible
copper damping means, especially with the larger gauge wire.

The end flanges are obviously larger in diameter than any of
the wire sizes wound on them, at, 1.975".  This plastic appears
to be tough to cut, and probably tin shears might work somewhat.
They are molded plastic, and have the halfs junction with slight
extrusions of plastic, which seems to be fairly easy to smooth
off.  The plastic coil spindles seem to be the toughest I've seen
over the years.

They are interesting in themselves, and possible seismic uses
are varied.  They have been around for some time, but I
think they could be interesting to see for some, in conjunction
with the Sean-Thomas Morrissey recent messages on coils.

Meredith Lamb








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