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Re: Auto compasses are fine
By:Nick Schade - Guillemot Kayaks
Date: 8/15/2001, 9:30 am
In Response To: Avoid Auto compasses (Paul G. Jacobson)

: a handheld compass, and a proper nautical compass that is deck mounted, are
: designed to be read from the top, while automotive compasses are designed
: to be read from the back. While this makes sense for a car driver who has
: one of these things on his or her dash, and is not comparing it to another
: compass, the readings are opposite what you get with a "normal"
: compass.

: let me elaborate. Suppose you are in, or next to, an automobile that is
: heading north. Since the manufacturers of these things assume that the
: compass will be mounted in front of the driver, the automotive compass
: will have a floating ball with the letter N on it, facing the driver. But
: to get this display, that N has to be on the SOUTH side of the compass. To
: make it more confusing, the letter on the NORTH side of the compass --
: plainly visible through the front window of the car, or from above, is a
: big "S".

: To make things even stranger, back-reading, automotive compasses, if you read
: them clock wise from above, should go N W S E, while handheld compasses
: would read N E S W.

This is exactly like many (most) marine compasses. Auto compasses are modeled after marine compasses and work in the same way. As long as you use them correctly, these compasses are the easiest to use. The compass you don't want as your primary navigation tool is a handheld "orienteering" compass. These are the typical boyscout compass on a clear plastic base with a rotating dial and a little moving needle with a red end pointing north.

These require that you dial in the course you want and then keep the needle centered in the north marker - "keep Red in the Shed". While this works fine as a back up, the fact that you need to fiddle with the compass in order to change your desired course makes them a hassle to use especially if the weather kicks up and you would rather keep your hands on your paddle instead of fussing with the compass. It also neccessitates that the orienteering compass be placed on your lap so you can do the fiddling and read it correctly. This requires that you look down to check your course. Looking at your lap can be disconcerting in big water.

A marine compass can be placed farther out on the bow where it is easy to see while you are also trying to keep your eye on the course ahead. You can also easily take a bearing by point your boat at your mark and directly reading the compass. The orienteering compass requires more fiddling.

Keep an orienteering compass in your PFD pocket for emergencies and use a direct reading marine (or auto) compass mounted on your boat. Know how to use both.

Messages In This Thread

Cheap Compass *Pic*
John Monfoe -- 8/11/2001, 3:08 am
Avoid Auto compasses
Paul G. Jacobson -- 8/14/2001, 10:58 pm
Re: Auto compasses are fine
Nick Schade - Guillemot Kayaks -- 8/15/2001, 9:30 am
Obviously I have been less fortunate :)
Paul G. Jacobson -- 8/15/2001, 9:41 pm
Re: Obviously I have been less fortunate :)
Nick Schade - Guillemot Kayaks -- 8/16/2001, 9:10 am
True and Direct on the same compass card
!RUSS -- 8/15/2001, 9:56 am
Re: Avoid Auto compasses- Why???
Dave S. -- 8/15/2001, 1:24 am
Why? Purely personal : They confuse me ! *NM*
Paul G. Jacobson -- 8/15/2001, 9:28 pm
Re: Cheap Compass
Brad -- 8/13/2001, 8:04 am
Re: Cheap Compass
John Monfoe -- 8/14/2001, 7:09 am
Re: Cheap Compass as backup
Erez -- 8/13/2001, 1:29 am
Cheap compass
!RUSS -- 8/11/2001, 2:24 pm
Re: Cheap compass
Dan -- 8/14/2001, 12:14 am
Re: Cheap compass
John Monfoe -- 8/14/2001, 7:02 am
Re: Cheap compass
John Monfoe -- 8/12/2001, 4:30 am
Re: Cheap compass
daren neufeld -- 8/12/2001, 10:00 am
Re: Cheap compass
John Monfoe -- 8/13/2001, 2:42 am
Re: Cheap advice :)
!RUSS -- 8/12/2001, 9:10 am
More Cheap advice :)
Ken Sutherland -- 8/13/2001, 4:00 am
Re: More Cheap advice :)
John Monfoe -- 8/14/2001, 7:23 am
Even Cheaper advice :D
!RUSS -- 8/13/2001, 9:41 am
You have great advise.
John Monfoe -- 8/13/2001, 3:39 am
Re: You have great advise.
Erik H -- 8/16/2001, 12:13 pm
Great Site Erick, thanks. *NM*
John Monfoe -- 8/19/2001, 5:59 am
Yup, tooth brush and tooth paste, too.
Tony -- 8/13/2001, 12:13 pm