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Glenn Ashmore
 
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Default Compass needle versus card for cruising

Regardless of the ultimate accuracy, a card will be much easier to use
on a boat than a needle. The card can be damped easier so it will
settle faster.

As an example of the extremes, I have a K&E pocket transit accurate to
..5º. It works great when I am walking off property lines but is
impossible to use on a boat. OTOH, I can get usable bearings within 2º
or so from my W&P puck in seconds.

Chris Doubleday wrote:
I am new to the world of compasses and sailing. My wife recently
purchased a sighting compass as a gift for me when sailing/cruising.
It is a traditional sighting compass with needle and mirror (Suunto
MC-2G-Global). I am more accustomed to using a compass with a compass
card and view finder. I suspect it will be difficult to get an
accurate bearing with the MC-2G-Global on a moving boat due to having
to adjust the bezel while sighting the landmark. Is this the reason
for the different design (card and finder) of the KB-20? The
MC-2G-Global does have a global needle which I underatdnw should help
with some of the pitching and rolling that will occur on a boat, but
it still seems like an error prone process, especially when trying to
get multiple simultaeous fixes as when dead recconing. The accuracy
is noted as 2 degrees, which I imagine is only attainable in the best
of conditions. Any opinions / experience with this sort of compass in
a cruising environment?


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
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