"Larry W4CSC" wrote in message
...
"Gordon Wedman" wrote in
news:XLGte.74286$9A2.12976@edtnps89:

He plans to mount it on a swing arm so that he can position it in the
companionway and see it from the helm.


You tell him for me that if that damned "swing arm" has a knob that turns
to lock it in place that will swing free when the knob is loose for him to
save his money. Geoffrey paid a fortune for this fancy aluminum dual arm
thing from Waste Marine and it's USELESS AT SEA! Any roll or pitch that
can loosen that damned screwlock does so and BANG!...there goes whatever
is
bolted to it into whatever it can bang it into....

USELESS....
http://www.westmarine.com/webapp/wcs...splay?storeId=
10001&langId=-
1&catalogId=10001&productId=76614&catalogId=10001& classNum=484&subdeptNum=1
42&storeNum=3
(add up all these lines that wordwrapped to see the exact POS we have.)
$174 and it doesn't even have a lock washer! If anything turns
counterclockwise from a roll...it has NO LOCK AT ALL and swings totally
free! How awful...looks nice, though....USELESS!!


My friend will probably build his own as he hates to pay for anything he
*thinks* he can build.
I put my JRC radar display on a couple of RAM mounts which are swing arms
that are probably similar to what you have. I find you can't really get
them to stay in place by just trying to turn the large knob.
What seems to work is to hold the knob and work the arm back and forth. You
can get things really tight that way. My radar stays in place but not yet
tested in rough water.