Should you trust your compass


(David Walker) #1

Generally yes, as long as you are certain it really points to magnetic north. Or more accurately that it aligns with the local magnetic lines. With everyone now days carrying around cell phones and such, which have magnets, it’s possible for the magnetic needle or card can become magnetized incorrectly and no longer point in the the correct direction if you are not careful to keep them stored apart. I am careful about this because I own low cost compasses and compasses that each could cover the cost of one or several tenkara rods. How to check it and maybe restore it.

https://www.youtube.com/watch?v=DZfHT_cNdMs

I’ve never really gone places where I actually need a compass to know which way to go. Terrain association is usually sufficient. I just like playing with compasses of different designs, and playing around learning different land navigation tricks. Just for fun. :wink: It’s not so important to know where you are as it is to know which way to go to get to where you want to go.

Some of the best info I’ve found can be found in the downloads of the files at the following website. The four part lessons, or the 20 modules that break down the info from the four part lessons into smaller bites. Module 17 & the Part 4 Land Navigation Supplement, which cover navigation without a map I find most interesting. Ded/ Dead Reckoning (deduced reckoning) and what some people call SOCKNAV, Sum of Connections Known Navigation. Or Vector navigation.
The documents are specific to the Cammenga Lensatic compass that has a magnetic card, which has to be used a little differently from the base plate magnetic needle type compasses. But otherwise the information applies to both types of compass.

http://landnavigation.weebly.com/downloads.html

The information from Reid Tillery is also quite good. He also writes about both types of compasses. And also does a great job explaining the UTM Grid system among other topics.

http://www.land-navigation.com/dead-reckoning.html

His Udemy Basic Land Navigation course is good too. Worth doing especially if you know little about finding your way in featureless terrain or terrain with to many features. :confused:

http://www.land-navigation.com/land-navigation-course.html

And several of his YT videos on his Florida Adventuring you tube channel are good. Such as his Mapless Land Navigation video.

https://www.youtube.com/watch?v=QSmMLm-wpOM

And his UTM Grid video - useful to know if you use topo maps or GPS.

https://www.youtube.com/watch?v=HonFxihqstU


(David Walker) #2

Ya might not get to where you want to go if you don’t know your reference point. T.S. Eliot thought a cat must have 3 different names. We have to understand that there are 3 Norths to understand when doing land navigation with a map.

There are 3 Norths to choose from: True North, Grid North, and Magnetic North.

https://maptools.com/pdfs/instructors/NorthReferenceSheet.pdf

Which one to choose?

And a bunch of different map datums to choose from when setting up your GPS.

https://maptools.com/tutorials/map_datum

And Zones:

https://maptools.com/tutorials/grid_zone_details

Some thoughts on why it’s a good idea to use a Compass with your GPS. And why you should think of the GPS as the backup means of navigation, not the primary.
(explained from an infantry perspective, including security, but largely applicable to anyone in an unfamiliar area, choosing to use one or the other to take advantage of which is the best tool for the task at the moment.)

https://youtu.be/ZeSLRT0iXdM?t=1m20s