Discussion: Thumb compass fundamentals

Hey all-

Just looking for the basics and also lessons learned for using a thumb compass for orienteering. I'm starting a transition to thumb compass soon.

My model will be the Brunton Jet Spectra 6.

Later!

Thumb compass was an easy transition for me because I was fairly new to orienteering when I got it, probably not much more experience than you. So it shouldn't take much getting used to. Basics:

-place compass on thumb
-hold map in same hand
-rotate map so north lines up with the needle
-go!

That's it! Have fun!

(and maybe others will have more useful information to give)

I used the plate base compass for the longest time and a couple years ago I switched:the thumb compass is amazing, so much faster, it's always on the map, I loved it eversince.

Cristina's directions sound just fine, especially the "go!" part, that's where I have trouble :) I also do occasionally turn the base plate to match the north lines, as a step 4, but the pro's are probably skipping this step nowadays.

I've rotated the bezel on my baseplate for adventure racing, but don't find it necessary when using a good O-map. I switch back and forth between thumb and baseplate without too much difficulty. The thumb compass is just too cumbersome in adventure racing where you often need to be using both hands for something.

The only thing I'd modify in Christina's directions is that you may want to rotate yourself rather than the map to get the lines match the needle.

you may want to rotate yourself rather than the map to get the lines match the needle.

Well sure, rotating the map itself isn't necessary... though I've seen some pretty entertaining attempts by people to rotate both map and body at the same time. This usually results in spinning all the way around and twisting one's arm underneath itself. Not that I would want to try to get anyone to do that... but it is entertaining.

Seems to be quite easy to use just on initial college-tries!

When I switched from having the baseplate compass on the map (almost like the thumb compass) to the real thumb compass, I was less precise when using the compass to go through bland areas. Now it don't drift that much anymore, after having some practice.

I have the compass on the map no matter what, so I can switch between thumb and base plate easily. For course setting I prefer the plate compass, so I don't have to tie knows with the thumb compass on my hand.

A safety tip: Attach a string on the thumb compass and put it around your wrist. You won't lose the compass when you hit a tree and after the race you take it off the thumb but it is still attached.

I would say the basis of thumb (and all compass in fact) is turn down/bend (sorry I am not sure of the term in english), oriented, thumb.
it's basically having always your map turn down/bend, always have it oriented and always having your thumb on the map at the place where you are.
Even if it's can normally be done with a plate compass I have felt it easier with a thumb compass. it's also even more important with a thumb compass as you usually are a little less accurate when you go straigth following oonly your compass.

turn down/bend = fold

it's also even more important with a thumb compass as you usually are a little less accurate

For me, a thumb compass is useful when I'm on a ridge-and-valley or other easily-read map, and am willing to sacrifice precise navigating by compass in the interest of speed.

But on bland, flat terrain with few catching features, I prefer a settable base-plate compass, where the needle and the direction to travel are superimposed upon each other. I find I have a better chance to spike that point feature at 400m with a base-plate.

I am relatively new convert from base-plate to thumb. Overall it has been positive experience for me but let me list few issues I had to deal with:
- I had to improve my map holding habits.
- I made more 180 degree directional mistakes in 3 month while still adopting to thumb compass then I have with baseplate in last 15 years
- I am not as precise with bearings in feature-less areas (seems like everyone else have similar problem).

Problems encountered above did not make me to consider switching back to base-plate. For the first problem I listed – I should have developed better map handling skills even while using baseplate. I got to pay more attention to needles north and maps north line to avoid 180 directional mistakes. For the last one problem with bearings – that’s a tough one however I do have some idea how to get better at it, like taking couple seconds longer to position myself into right direction before taking a plunge through featureless area and practicing taking bearings with thumb compass.

http://www.orienteering.nb.ca/falcons/system.htm
http://www.orienteering.nb.ca/falcons/mapreading.h...

Here is some links to my club site that show certain map reading strategies and systems.

Good links Natasha.

I like the following comment under first link.

6. Relocation
Stop, admit you are "lost"

Com'on... who is going to admit that they are "lost"... :)

1. On bland, flat terrain, the old boy scout method of 'spot a tree' is useful - then recheck compass and spot next tree. It really doesn't cost time since there usually is a tree on your way :); just pick one out.

2. For 180's, it helped when someone pointed out that ALL letters and numbers on a map (including control #'s) face the same direction. (I learned how much I subconciously rely on that when a Texas map with a large title on the edge, thus rotated by 90 degrees, really messed me up a while back!)

1. On bland, flat terrain, the old boy scout method of 'spot a tree' is useful - then recheck compass and spot next tree. It really doesn't cost time since there usually is a tree on your way :); just pick one out.

I agree with this one. I used to do "tree spotting" trick earlier in my career but slowly got away from that habit when using baseplate. However this approach crossed my mind when I notice flaws with bearings using thumb compass

Wow - great stuff so far from all. Thanks!

2. For 180's, it helped when someone pointed out that ALL letters and numbers on a map (including control #'s) face the same direction.

yes, also pit and small depression are oriented to the north.
line of the marshes are perpendicular to the north line

i've always used thumb compass, and i can't orienteer without it... it just don't feels real with a regular compass.

What method is there except "spot a tree, go to it, repeat"??

I can't really rermember ever having done that, and there are definitely places where it doesn't work well due to lack of trees. I much prefer to pay attention to stuff that's actually on the map.

pay attention to stuff that's actually on the map.

Well, here in the midwest we have a lot of terrain that is (1) flat; no readable contours, (2) indistinct vegetation boundaries, and (3) few handrails or point features.

In such terrain you're left with only your compass and pace count...and the better you're able to run out a lengthy bearing line at speed, the better you'll do in competition. 'Spot a tree' is one technique to develop synthetic point features to guide you as you run.

It's true that I live in the northeast US, but I've been to orienteering meets all over the US (37 states and 7 Canadian provinces, plus a few European countries), and I've found that reading the map works pretty well wherever I've been.

That said, I realized that I have used the "spot a tree" method at least once recently: at the Night-O Champs this past summer in Wyoming, On the 4th leg, after crossing the road, I headed for the group of trees at the fence, then for a pair of trees near some stony ground north of the control, and that got me close enough to to cross the reentrant and spike the control. On the other hand, although I was spotting trees, they were trees that are on the map.

2. For 180's, it helped when someone pointed out that ALL letters and numbers on a map (including control #'s) face the same direction.

Just don't rely on that for Adventure Racing or Rogaining!

Or for the names of streets, streams, etc. Unless my name is listed under cartography. In that case all text will be aligned to magnetic north (with the exception of mysterious messages that are 2 point or smaller that you can't read anyway).

2. For 180's, it helped when someone pointed out that ALL letters and numbers on a map (including control #'s) face the same direction.

Just don't rely on that for Adventure Racing or Rogaining!

Heh! I remember a US Relay Champs meet one year where the numbers next to each control on the map were oriented to be right-side up as you were reading the leg heading to that control. It wasn't until after I'd finished my run that I figured out why I'd messed up a leg or two. (Trivia question: what year and state?)

I also remember a Ski-O World Cup race where the entire map was mistakenly printed oriented to south. I made it all the way around the first loop without noticing. Then when I picked up my 2nd map at the map exchange, slapped it in my holder and spun the holder to quickly line up the mag-north lines with my compass, I just stood there in front of hundreds of spectators trying to figure out why nothing made any sense. Eventually I got it lined up with the nearby powerlines and got moving again, but never fully figured out what went wrong until after the finish. (It did help me to understand later why on my first loop I'd passed a few people who I knew to be competent navigators standing at intersections staring at their maps acting like they were lost.)

(Trivia question: what year and state?)
Brandywine, Delaware, 1991. First US Relay Champs to use the "modern" format, and the first USOF-sanctioned A-meet in Delaware.

Great discussion, I do adventure racing so I find myself on a tight budget - otherwise I'd get a thumb compass.

I have a baseplate that I hold in my hand. It is attached to my wrist with thick and soft piece of string that I removed from a designer store Shopping bag.

The string was long enough to fashion a small loop (thumb/finger) and a big loop (wrist). The compass on occasion will flail around but it is mostly controlled and convenient.

I would have thought that the compass would have come with a "piece of string", a "Forearm strap" or a Thumb wrap - I guess when it does we pay the price...

The long and short, I'm happy with my arrangement; Orienteer on...

Where I live, there's always contours on every part of almost every map, but there is not enough of other stuff to navigate with.

Nobody's mentioned it yet, but thumb compasses are a pain if you're using trekking poles in a long Rogaine or adventure race. We only use poles for races 12 hours or longer, so I use a baseplate for these after managing to lose my thumb compass repeatedly at the 2005 North American Rogaine champs. (Had a spare baseplate).

I have one Moscow capsule I could switch between a thumb and base plate, but after losing and eventually finding the capsule, I've ordered a second capsule and a spare retaining ring.

I believe that and paddling and ski-O are the main reasons Silva produces the compass that straps around your wrist and thumb with the bezel sitting atop the base of the thumb. Not quite as close to the map as a thumb compass but still always there. As far as I recall, that's what I've been seeing Pam James use even in regular orienteering the last few years.

I often take bearings when I navigate through semi-flat and feature rich area with catching feature behind instead of trying to read every feature in between. I find that when I navigate through feature rich area I have to slow down and even with slowing down I am prone to make mistakes because with too many features to read. I can cruise through area without thinking, running faster when I take bearings in situations like that.

Maybe I missed it in this thread, but what is the actual "cause" of people having more difficulty with bearings when they use a thumb compass?

I have used a thumb compass in adventure races, by just clipping it to my Camelback and using it like a baseplate. Then when I got to tougher nav sections, I would take it off and wear it properly. I figured out the first time I did this that clipping it directly to the carabiner I had led to interference. So I added a lanyard and it worked well.

what is the actual "cause" of people having more difficulty with bearings when they use a thumb compass?

Various direction-finding methods, in order of accuracy:
1. Moss on the North side of trees
2. Sun's direction at noon
3. Thumb compass
4. Settable base plate compass
5. Sighting compass
6. Surveyor's transit and pole

The reason a thumb compass is less accurate is because you do not actually "set" the compass...in normal use, you merely place the compass on your desired map route, rotate your body until the compass' needle and the compass rose on the map appear to be parallel, and then proceed forward. Aligning the 1" needle with north on the map, and keeping it there as you run, takes practice, and is never as accurate as a settable base plate compass, where your set bearing and the compass needle are directly on top of each other.

I find thumb compass very accurate when taking a bearing.. I should say " when TAKING THE TIME in taking a bearing".I like a fast and accurate compass. difference between the fastest silva and not the fastest silva, is some good dollars, maybe a second or so less time in "stabilizing" the needle and if you did not allow that extra second for "the no so fast silva", then you might make an error and spend some time , and then of course the excuse is the compass, maybe the map, but never you as you" saved" that extra second.

I agree Nick. I used my thumb compass at the North American's this year and in flat terrain was very happy with the accuracy of my bearings.

I too love my thumb and am "lost" without it. When teaching clinics, I bring both, but would rather have the thumb.

>Silva produces the compass that straps around your wrist and thumb

I use this in AR but not O. I take it off the thumb and use only on the wrist for the MTB and paddling. Loop over the thumb for the orienteering/trekking section or bring out the baseplate (hanging around my neck...pause..pause...NOT).

2. Sun's direction at noon

I have actually used this many times, mostly in ski-O. Sometimes despite having them with me I don't even bother taking a compass out on the course with me if it's a sunny day. The thing is, during ski-O time of the year, if you can see the sun, it's pretty close to south (in northern hemisphere of course). Most ski-O start times are within a couple hours of noon one side or the other.

And... of course JJ's answer to my trivia question (above) was correct. Maybe that was too easy. For a harder one, name the year and country of the world cup race where the map was printed oriented to south.

I could never get my bearings when wandering around Sydney Australia, until it dawned on me (pun intended) that the sun was North at noon. I guess I subconsciously use sun position for sense of direction far more than I know.