hey everyone,
im trying to "adjust" the compass on my cd25. i bought the boat used and there were no manuals for anything so im not sure how the adjustment screws on the compass work. there are 2 that i can see, one in the middle and one on the right side. each one has an effect on the compass, but i dont know how to use these. does anyone know what im talking about here?
thanks!
dan
compass question
Moderator: Jim Walsh
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len
Re: compass question
dan
the screws control magnets, one for E-W and one for N-S - there have been some fairly recent posts on using GPS to adjust the compass - to simplify: you drive the boat on a known course (due E, due W, due S or due N) and use the screw to make the compass correspond to that course - you go back and forth until you have it as close as possible and then do the perpendicular course - it helps to have someone else aboard, it helps to make the courses a few miles long, it helps to have landmarks (e.g. buoys) to go between, and you can't use the moment to moment GPS reading, you need to use the GPS heading - when you are done you will hopefully have removed most of the deviation from the compass
len
the screws control magnets, one for E-W and one for N-S - there have been some fairly recent posts on using GPS to adjust the compass - to simplify: you drive the boat on a known course (due E, due W, due S or due N) and use the screw to make the compass correspond to that course - you go back and forth until you have it as close as possible and then do the perpendicular course - it helps to have someone else aboard, it helps to make the courses a few miles long, it helps to have landmarks (e.g. buoys) to go between, and you can't use the moment to moment GPS reading, you need to use the GPS heading - when you are done you will hopefully have removed most of the deviation from the compass
len
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Don Sargeant
Re: compass question
Chapman's "Seamanship and Small Boat Handling", a must have book in my opinion, gives clear instructions on how to "box the compass"
dan wrote: hey everyone,
im trying to "adjust" the compass on my cd25. i bought the boat used and there were no manuals for anything so im not sure how the adjustment screws on the compass work. there are 2 that i can see, one in the middle and one on the right side. each one has an effect on the compass, but i dont know how to use these. does anyone know what im talking about here?
thanks!
dan
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Chris Scheck
Get a Chapman's
Yes, you should definitely have a copy of Chapman's. It's the ultimate coffee table book -- it takes a coffee table to hold it!
The only question is do you want to spend $40 or so for a new one, or do you want to pick up an old copy at a used book store.
By the way, there is an alternative to boxing the compass yourself ... you can pay a professional adjuster to do it. They usually advertise at most boatyards.
cscheck@aol.com
The only question is do you want to spend $40 or so for a new one, or do you want to pick up an old copy at a used book store.
By the way, there is an alternative to boxing the compass yourself ... you can pay a professional adjuster to do it. They usually advertise at most boatyards.
cscheck@aol.com
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Jon
Or The Annapolis Book of Seamanship
The Annapolis Book of Seamanship by John Rousmaniere is more sailing specific. This book also covers every topic any sailor would ever need.
Jon
CD25 Sovereign
Jon
CD25 Sovereign
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Nautical Traditions Offic
Re: www.ritchienavigation.com.......
Captain Dan,
Look at the listed web site. They have a method of turning your compass with the use of a GPS. They also ID which screw to turn for which adjustment. I did it on Hanalei and it worked very well! It doesn't take much adjustment to make a BIG difference!
Hey, want to cheat a little, to see if you are even close, walk the dock and ask each skipper what the heading on his compass is reading when they are tied to the dock. If pointing the same way(the vessels), at my marina, slips point almost east, they should all be reading pretty close to the same degrees. I wouldn't set the compass this way, but it will let you know if ya are way off!
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
Look at the listed web site. They have a method of turning your compass with the use of a GPS. They also ID which screw to turn for which adjustment. I did it on Hanalei and it worked very well! It doesn't take much adjustment to make a BIG difference!
Hey, want to cheat a little, to see if you are even close, walk the dock and ask each skipper what the heading on his compass is reading when they are tied to the dock. If pointing the same way(the vessels), at my marina, slips point almost east, they should all be reading pretty close to the same degrees. I wouldn't set the compass this way, but it will let you know if ya are way off!
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
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Nautical Traditions Offic
Re: "Boxing" the compass.....
Captain Sargeant,
With all due respects Captain, "boxing" the compass occured when a vessel lost her stearage way due to slight or no winds. The vessel would slowly turn about the compass and "Box" it! Turning a compass is something else entirely...I remain Sir, your most humble servant....
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
Nautical Traditions Officer
New England Fleet
CDSOA
With all due respects Captain, "boxing" the compass occured when a vessel lost her stearage way due to slight or no winds. The vessel would slowly turn about the compass and "Box" it! Turning a compass is something else entirely...I remain Sir, your most humble servant....
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
Nautical Traditions Officer
New England Fleet
CDSOA
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Don S.
Re: "Boxing" the compass.....
...and respects to you, sir.
But it would appear we're both incorrect. A short web search shows that "boxing the compass" refers to naming the 16 cardinal points in order. A test for apprentice seamen(seapeople?). As for "turning the compass" I've not heard that term so I can't misuse it yet. I think I'll re-read Chapman's tonite just for sport -- I haven't looked at it for at least 25 years.
Don Sargeant
~~COQUINA~~ etc.
But it would appear we're both incorrect. A short web search shows that "boxing the compass" refers to naming the 16 cardinal points in order. A test for apprentice seamen(seapeople?). As for "turning the compass" I've not heard that term so I can't misuse it yet. I think I'll re-read Chapman's tonite just for sport -- I haven't looked at it for at least 25 years.
Don Sargeant
~~COQUINA~~ etc.
Nautical Traditions Officer wrote: Captain Sargeant,
With all due respects Captain, "boxing" the compass occured when a vessel lost her stearage way due to slight or no winds. The vessel would slowly turn about the compass and "Box" it! Turning a compass is something else entirely...I remain Sir, your most humble servant....
Dave Stump
Captain Commanding
s/v Hanalei CD-30C "#1"
Nautical Traditions Officer
New England Fleet
CDSOA