Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 07-03-2011, 17:18   #76
Senior Cruiser
 
jackdale's Avatar

Cruisers Forum Supporter

Join Date: Mar 2008
Location: Calgary, AB, Canada
Posts: 5,048
Images: 1
Re: Magnetic North Shift

Quote:
Originally Posted by cal40john View Post
Do you mean the magnetic rose is far enough off in one year that you can see errors in your navigation? What are you doing that 10 minutes of error in the PNW show up?
In theory yes, practically no. 2005 18.5E 8'W change, 2011 18E

[QUOTE]
__________________

__________________
ISPA Yachtmaster Ocean Instructor Evaluator
Sail Canada Advanced Cruising Instructor
IYT Yachtmaster Coastal Instructor
ASA 201, 203,204, 205, 206, 214
As I sail, I praise God, and care not. (Luke Foxe)
jackdale is offline   Reply With Quote
Old 07-03-2011, 17:20   #77
cat herder, extreme blacksheep
 
zeehag's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 17,777
Images: 56
Send a message via Yahoo to zeehag Send a message via Skype™ to zeehag
Re: Magnetic North Shift

magnetic north can shift all it wantas to-- when the continents move, please send me an email.
__________________

zeehag is offline   Reply With Quote
Old 07-03-2011, 17:22   #78
Senior Cruiser

Cruisers Forum Supporter

Join Date: Dec 2006
Location: Seattle
Boat: Cal 40
Posts: 2,401
Images: 7
Re: Magnetic North Shift

Quote:
Originally Posted by TheWatchman View Post
Which manual are you referring to?

As I have noted, and you point out, the chart states annual deviation of 5 degrees or as you wrote in this case 4 degrees.

Yet, the news states we are now accelerating to 10 degrees.

5 degrees is a lot of difference to me and if the rate increases?

So my question is how to validate appropriate deviation?
MINUTES! not degrees. 10/60th of a degree per year.

And the 4 degrees was the variation in 1985 when the chart was made, not the change in variation. The bottom of the inside of the rose said 8 MINUTES per year. So he multiplied 8 divided by 60 times the number of years to get the current variation difference, which was 0.75 or 3/4ths of one degree different than what the rose showed in 1985.
__________________
cal40john is offline   Reply With Quote
Old 07-03-2011, 17:26   #79
Senior Cruiser
 
jackdale's Avatar

Cruisers Forum Supporter

Join Date: Mar 2008
Location: Calgary, AB, Canada
Posts: 5,048
Images: 1
Re: Magnetic North Shift

Quote:
Originally Posted by zeehag View Post
magnetic north can shift all it wantas to-- when the continents move, please send me an email.
They are moving right now, (Plate Tectonics) what is your email address.
__________________
ISPA Yachtmaster Ocean Instructor Evaluator
Sail Canada Advanced Cruising Instructor
IYT Yachtmaster Coastal Instructor
ASA 201, 203,204, 205, 206, 214
As I sail, I praise God, and care not. (Luke Foxe)
jackdale is offline   Reply With Quote
Old 07-03-2011, 17:30   #80
Registered User
 
sww914's Avatar

Join Date: May 2009
Location: Punta De Mita
Boat: Vagabond 39 Hull # 1
Posts: 1,842
Re: Magnetic North Shift

Put some 3M 5200 under it and it won't ever move again. Not even if you want it to.
__________________
sww914 is offline   Reply With Quote
Old 07-03-2011, 18:26   #81
Registered User
 
TheWatchman's Avatar

Join Date: Feb 2011
Location: Channel Islands, CA
Boat: Spencer 53 Ketch
Posts: 42
Images: 2
Re: Magnetic North Shift

I stand corrected.

Thank you Jackdale and Cal40John.

Graveyard shift is kicking my ass!

The articles do state minutes, not degrees. Sorry.
__________________
TheWatchman is offline   Reply With Quote
Old 07-03-2011, 18:29   #82
Senior Cruiser

Cruisers Forum Supporter

Join Date: Dec 2006
Location: Seattle
Boat: Cal 40
Posts: 2,401
Images: 7
Re: Magnetic North Shift

Quote:
Originally Posted by TheWatchman View Post
I stand corrected.

Thank you Jackdale and Cal40John.

Graveyard shift is kicking my ass!

The articles do state minutes, not degrees. Sorry.




__________________
cal40john is offline   Reply With Quote
Old 07-03-2011, 19:12   #83
Registered User
 
stevensuf's Avatar

Join Date: Dec 2010
Location: Back in Scotland!
Boat: Gib sea 43
Posts: 840
Images: 10
Re: Magnetic North Shift

But does the deviation not change as well with heel angle?
__________________
stevensuf is offline   Reply With Quote
Old 07-03-2011, 19:13   #84
cat herder, extreme blacksheep
 
zeehag's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 17,777
Images: 56
Send a message via Yahoo to zeehag Send a message via Skype™ to zeehag
Re: Magnetic North Shift

Quote:
Originally Posted by jackdale View Post
They are moving right now, (Plate Tectonics) what is your email address.
the only constant is change--is time to go sailing.....
zeehag is offline   Reply With Quote
Old 07-03-2011, 20:34   #85
Registered User
 
bewitched's Avatar

Join Date: Sep 2009
Posts: 885
Images: 3
Re: Magnetic North Shift

Quote:
Originally Posted by stevensuf View Post
But does the deviation not change as well with heel angle?
Not as much as when you stand next to the compass wearing your leatherman
__________________
bewitched is offline   Reply With Quote
Old 07-03-2011, 22:42   #86
Registered User

Join Date: May 2009
Location: Vancouver, Wash.
Boat: no longer on my Cabo Rico 38 Sanderling
Posts: 1,794
Send a message via MSN to John A
Re: Magnetic North Shift

Quote:
Originally Posted by bewitched View Post
Not as much as when you stand next to the compass wearing your leatherman
Don't keep your AK47 in the cockpit as it will cause the compass to swing!
__________________
John A is offline   Reply With Quote
Old 07-03-2011, 23:08   #87
Registered User
 
Blue Crab's Avatar

Join Date: Sep 2009
Location: Hurricane Highway
Boat: Cal 29
Posts: 3,883
pirate Re: Magnetic North Shift

Didn't take us long to get back to some decent blather.
__________________
Blue Crab is offline   Reply With Quote
Old 08-03-2011, 00:13   #88
Registered User
 
bewitched's Avatar

Join Date: Sep 2009
Posts: 885
Images: 3
Re: Magnetic North Shift

Quote:
Originally Posted by John A View Post
Don't keep your AK47 in the cockpit as it will cause the compass to swing!
Ah, you've probably got a cheap China copy there.

I believe the extra few dollars for the high nickel content is well worth it for piece of mind.

Now, back to serious matters - if I magnetize my anchor and always set it poleward of the boat, do I need as much scope?
__________________
bewitched is offline   Reply With Quote
Old 08-03-2011, 00:29   #89
Registered User
 
Hillbillylad's Avatar

Join Date: Aug 2010
Boat: Westerly Centaur
Posts: 207
Re: Magnetic North Shift

I guess the problem is and perhaps always was, referring to it as "North". It was never really "North" even when the vikings were following their lodestone on a piece of string. It is rather a reasonably constant point of reference is all. If it flipped totally we would just paint the other end of the compass pointer and be happy. As long as we can adjust for the variation I don't see the big deal. Your compass will always point to the big magnetic, global lump, regardless of what you call it.
Though I do understand how people have got lost believing it is an infallible and eternal lump of metal on the North pole.
__________________
Hillbillylad is offline   Reply With Quote
Old 08-03-2011, 00:40   #90
********* Emeritus
 
SaucySailoress's Avatar

Cruisers Forum Supporter

Join Date: Apr 2010
Posts: 8,236
Re: Magnetic North Shift

Quote:
Originally Posted by cal40john View Post
Well to make the data in my post relate more directly to your question, at the current rate of 10 minutes per year, my charts have to be 6 years old to make the magnetic rose 1 degree off. I don't think I can hold a course that close.
LOL!!!! I think you probably can.... But OP seems to be concerned about a rapid shift:

Quote:
Originally Posted by TheWatchman View Post
Anyone concerned about the headlines detailing a rapid shift of magnetic north towards Russia at an extremely accelerated pace?

How does this affect us as navigators. Deviation recommendations will have to be adjusted?
I followed the links, and they confirm the rumours that the poles are due to flip any time soon. Now that doesn't worry me when it comes to chart use - since according to the book us women need to turn the map upside down when we're travelling South anyway. Shouldn't be too much hassle to rotate the compass too.

But... how might this affect the GPS - which I do need in order to set a course which to steer by the compass (I'll be honest, I've never used a compass rose in real life, only training courses....)?
__________________

__________________

SaucySailoress is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Where to Buy Throttle and Shift Lever ? Garrett Engines and Propulsion Systems 5 14-05-2010 05:12
Stuck Shift Lever Eddie Engines and Propulsion Systems 5 29-03-2010 07:15
Stiff Gear shift mayphoto Propellers & Drive Systems 4 14-08-2008 20:48
Magnetic Induction Cooktops Lodesman Provisioning: Food & Drink 15 11-03-2007 20:26



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 05:48.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.