Mention the word compass around me and I’ll most likely utter Suunto MC2. It’s almost involuntary. Not that there aren’t other good compasses, it’s just the one I’ve seen used extensively to teach non-land navigators how to navigate, and the one I’ve used the most as well.
In fact, I just taught 11 students in my recent fieldcraft course to navigate with 1 meter accuracy with them, in the dark no less.
As I’ve used this compass there are some ideas I’ve had on how to improve it, or at least use it better. A little 2 page instruction sheet or even YouTube video won’t teach you nearly what you can learn by actually going out and training, and that’s where I’ve learned the most.
I’ve had some experiences that made me scratch my head as I tried to understand them, but I stuck with it and figured these out. One of the major ones was that in some areas I would shoot an azimuth, only to get to the landmark, and shoot a back azimuth that ended up being significantly different.
I would run into this situation while building my azimuth courses, and my first instinct was to attribute the phenomenon to a magnetic anomaly in the soil. The first time I had this happen I was next to a big pile of rock, so it kind of made sense. The next time though, there was nothing around to blame it on. Guess the buck has to stop here after all.
What I realized was that every time I observed this phenomenon, I was shooting azimuths going up hill or down. But I was aiming my compass perfectly through the vee notch like the instructions state. And that was exactly what I was doing wrong.
By using the Vee notch while pointing up or down hill I wasn’t holding my compass level. This caused my compass needle to drift, giving me a different reading than it should have. Then when I’d get to the landmark and shoot a back azimuth, the phenomenon would switch since I was facing the opposite direction.
So long story short, I needed a compass that I could ensure I was holding level. Shooting an azimuth is no different than shooting a rifle really, consistency is still accuracy.
I searched around and couldn’t find anyone making one so I decided to try it myself.
I ordered some of these small levels, not exactly sure of how I was going to use them. I spent a bit of time fiddling around with different methods of mounting it and I think I’ve got a good one.
The lid on the compass is square and goes over the round bezel of the compass. This leaves open areas at the corners, and that’s right where I found I could put the level.
After checking to make sure my bubble level was accurate, I then put the level onto the baseplate and closed it inside the lid. Then I flipped the compass over and marked a hole that would be underneath the level. It didn’t have to be centered, since it’s just for epoxy to run out of. I thought this might lock the level to the baseplate better.
Hole viewed from top, it’s a 1/8” hole
So this works really well for going up hill where I can utilize the upper vee notch in the lid. But going down hill is another story. By the time I get the compass level, I’m aiming out into space and can’t utilize either vee notch on the compass.
The way I rectified this was to tie my dummy cord using a Lark’s head knot onto the compass base and use the S-biner on the other end hooked around my belt. I can quickly unhook the s-biner from my belt to hang free, and utilizing a Marline spike hitch and a hefty stick I can then make a plumb bob.
Now it’s just a matter of lining up the needle, leveling the compass, and steadying my plumb bob. Just use the string like you would a vee notch and sight onto a distant object down hill.