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Old August 27th 10, 09:10 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
Posts: 1,336
Default Best plastic for antennas, machining

On Fri, 27 Aug 2010 09:16:57 -0700 (PDT), Tim Shoppa
wrote:

On Aug 27, 12:10*pm, Michael Coslo wrote:
Afternoon everyone,

* * * * I'm rebuilding my Bugcatcher antenna. It works well, but the XYL had a
bit of an accident last year when we had a big snowstorm, the leaves
weighted down the limbs, and the antenna, which was strapped down, still
managed to introduce itself to a limb.

* * * * Anyhow, the original antenna was mounted using 1 inch thick plexiglass,
with holes drilled to run the mast through, and tapped screw holes to
mount to the back up plate, in turn mounted to the spare tire holder.

* * * * I'm trying to make something a little prettier now that I'm rebuilding it.

But the thing is, I'm curious about the material. Is there any
particular material to avoid? I know Plexi works, but what about PVC?
Delrin? Bondo? 8^) Miiling, water absorption, etc?


Polycarbonate, polycarbonate, polycarbonate.


Fiberglass, fiberglass, and more fiberglass. It bends, it can easily
be repaired with a surfboard repair kit. It tolerates impacts better
than polycarbonate or plexiglass tubing. It's also UV resistant (when
coated with Krylon):
http://www.mgs4u.com/fiberglass-tube-rod.htm
$10 for 8ft of 1" plus shipping.

Polycarbonate is truly a wonderful material. I don't care what all
those people complaining about bisphenol-A say, polycarbonate is king.


There's some BPA in the epoxy resins used to bond the fiberglass matt
together. Don't drink out of your antenna, and you'll be fine.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558