View Full Version : Type of Compass?
NeanderJoel
10-05-2012, 07:50
I've just purchased myself a compass, map and map reading guide to go and teach myself navigation in the bush. I bought a fairly basic compass and the scale on the sides is in metric, seeing as I live in Australia. I'm just wondering whether I'll need to upgrade the compass once I get to america to something a little more fancy and whether you need the scale thing. Oh the guide came with a "map card" with a grid reference guide, a compass rose and a bearing guide. Did you guys have to use something like that on your hike?
peakbagger
10-05-2012, 08:04
Unless you are lucky, you will need to buy a new compass as most compasses are calibrated for use in either the northern Hemisphere or the Suthern Hemisphere. The difference is how they balance the needle, if you try to use the "wrong" one, the needle will dip down when the compass is held level. There are some compasses that have universal calibration that wokr anywhere. I will let others comment on the actual uses for a compass on on the CDT.
colorado_rob
10-05-2012, 08:09
Unless you are lucky, you will need to buy a new compass as most compasses are calibrated for use in either the northern Hemisphere or the Suthern Hemisphere. The difference is how they balance the needle, if you try to use the "wrong" one, the needle will dip down when the compass is held level. There are some compasses that have universal calibration that wokr anywhere. I will let others comment on the actual uses for a compass on on the CDT. True, this. I had a mountaineering student from South Africa, moved up here, her compass was really screwy. the magnetic field lines up here are oriented differently up/down vs. down there. As PB just said, balanced wrong.
A simple 1-oz Silva compass is fine. Other features are just wasted weight IMHO.
Neander, are you hiking the AT?
I didn't carry and never felt I needed a compass on the AT. I did meet some weekenders that were totally confused because they were using a compass and a guide book which was telling them a side trail was to the east but was really compass west. The guidebooks generally use east and west as right and left of the trail. Sometimes the when heading north on the AT you really heading anywhere but north.
bamboo bob
10-05-2012, 08:12
I just took a compass course at REI in Boston. Six hours of tromping around in the woods. Definitely worth it. Many compasses have a calibration screw so you can add or subtract the declination for the region you are in. But its not big deal to add 15 or whatever degrees as needed. Looking to the CDT next year. I "knew" of course how to use a compass but I never did triangulation before. On the AT and PCT a compass was just weight but some people think I need one for the CDT.
NeanderJoel
10-05-2012, 08:28
Don H - I just hiked the AT this year, I did have a compass but more because it was a gift from my brother than any other reason. The only time I used it was when I went 50 yards off the trail to 'use the bathroom'. I'm planning on doing the CDT next year, as long as I can save up the money. They don't seem to do map and compass courses here in Perth, it's just not as popular over here I guess.
Peakbagger - that would explain why it wasn't working properly!
The Green Mountain Club has a fantastic 7 part YouTube video series on how to use a map and compass. I learned more watching it than reading my book......
Check it out here:
http://www.youtube.com/playlist?list=PL79D437A59BF38E4F
Cheers!
The Old Boot
10-05-2012, 09:18
The Green Mountain Club has a fantastic 7 part YouTube video series on how to use a map and compass. I learned more watching it than reading my book......
Check it out here:
http://www.youtube.com/playlist?list=PL79D437A59BF38E4F
Cheers!
Can you check that link please - maybe it's because I'm not in the US but it says that the video doesn't exist...sigh
fiddlehead
10-05-2012, 09:42
OP: Do you have a GPS?
You should take both although many do the CDT without a GPS (I wouldn't want to)
For those who say you don't need a compass are probably not CDT (successful) thru-hikers.
There are times on the CDT where there is no trail, or you may be on a maze of dirt roads or trails (or cowpaths) with no idea of which one is the one you prefer being on.
With no CDT trail markings.
Now, to be out there without a compass, or GPS would mean.............well, let's just say you'd be out there a long time.
Most hikers anymore use the Jonathon Ley maps I beleive.
These maps have an interesting thing in that in the center, they have a point that you can put into your GPS and then see how far away (and at what bearing) you are from it. So, then it's easy to figure out exactly where you are (or not really exactly but, pretty good)
Now some triangulate their way up the trail.
That's OK if you know which mountain tops you are looking at, and it's not foggy, nighttime, or snowing too hard.
You should also understand magnetic deviation as it can make a difference.
What I did most days: Either the night before or early morning, spend some time with my GPS and put some points in it. (waypoints that I want to hit).
Then when it's time to hike, turn it on, get your signal locked in, and check the bearing and distance to the 1st one of the day.
Turn off the GPS (saving battery) and use your compass to follow that bearing.
the distance should tell you how long it should take you.
Say, the first one is 7 miles away.
AFter about an hour and a half to 2 hours, turn on the GPS again and see how close you are.
Remember, the newer GPS's find satellites quicker, using less battery.
Anyway, that's how we did it 10 years ago.
Someone more recent can update me on how it's done these days.
As far as your compass being metric, I don't see that it matters.
Just so either you can set the deviation or, you are good at math.
You'll learn a lot out there and be a whiz when you are finished.
Good luck.
NeanderJoel
10-05-2012, 09:59
Thanks spoke, I'll check it out soon.
Fiddlehead - Yes I do have a GPS and I'm planning on taking it too, but I'd like to try and keep it as a backup and primarily use the map and compass. I do, however, have a shocking sense of direction so I may be using the backup quite regularly!
That's an interesting way of doing it, is that for when you're bushwacking and walking a straight line or was it more to make sure you're still headed the right direction on the trail?
peakbagger
10-05-2012, 10:50
Over on the east coast of the US a declination adjustment screw is real handy as we are 17 to 18 degrees offset from true to magnetic.
I am spoiled and use a Suunto sighting compass for AT boundary work but havent laid out the big bucks for the one with adjustible declination http://www.benmeadows.com/brand/Suunto-4294965769/?gclid=COvgr6OQ6rICFQKe4AodZhsARg&cid=RG0480&ef_id=UG70HgAAUlZMlkAz:20121005145214:s
They are real handy for running a bearing, just look at the bearing with one eye and pick a point in the distance to head to.
In case one of the posters is confused (not the OP) , the declination adjustment available on some compassses is not related to the "needle" dip issue.
Can you check that link please - maybe it's because I'm not in the US but it says that the video doesn't exist...sigh
Try these links to the entire Green Mountain Club Map and Compass mini-course:
Video 1
http://www.youtube.com/watch?v=p584IPVf0-w&list=PL79D437A59BF38E4F&index=1&feature=plpp_video
Video 2
http://www.youtube.com/watch?v=38YY8SgvDXI&feature=relmfu
Video 3
http://www.youtube.com/watch?v=6SkpP8QW5Ro&feature=relmfu
Video 4
http://www.youtube.com/watch?v=jxxBgyksWko&feature=relmfu
Video 5
http://www.youtube.com/watch?v=ZFuq-aShdpo&feature=relmfu
Video 6
http://www.youtube.com/watch?v=af1jUZyXODY&feature=relmfu
Video 7
http://www.youtube.com/watch?v=V6lr4LNt1hg&feature=relmfu
Odd Man Out
10-05-2012, 11:35
I just use a cheap compass. You might need to get a North American compass as others have pointed out so that the needle is balanced. I don't use the scale. The scale is on the map and each map is different anyway, so I just use the "1 finger=1 mile" or "2 fingers=5 km" system.
CAUTION - SCIENCE ALERT!
By the way, the fact that the magnetic field is not usually parallel to the earth has biological implication. It has been found that there are bacteria that produce small iron crystals in their cells and that they can use these to determine N from S using the Earth's magnetic field. The problem was they could not figure out why a bacteria would need to know N from S (it's not like they are migrating south for the winter, like birds). Then then determined that because the magnetic field was not parallel to the Earth, the bacteria could use their internal compass to determine up from down. It seems that when you are only 1 micron long and suspended in water, the force of gravity makes it difficult to know "which way is up", but using a compass to figure that out helped the bacteria find food and oxygen. They found that southern hemisphere bacteria of the same species had their internal compass oriented the opposite way.
colorado_rob
10-05-2012, 12:22
CAUTION - SCIENCE ALERT!
By the way, the fact that the magnetic field is not usually parallel to the earth has biological implication.... cool stuff, thanks for sharing! i'll add to the Nerd content a bit too... looks like we're getting ready to do a magnetic pole-flip in a couple/few hundred years or so. This apparently happens every so-many milennia. The magnetic pole is moving fast these days, something like 1/2 a degree every 10 years. During the pole-flip, our compasses will be really whacky, basically useless. Plus the earth's "shield" from various solar rays will be very weak. Buy sunscreen futures! Google this all up if interested. Here's one example:
http://phys.org/news/2011-11-magnetic-pole-reversal-geologic.html
Please forgive the (additional) thread drift. I could not resist.
garlic08
10-05-2012, 13:33
On my CDT hike, I used the cheapest, lightest Silva compass I could find, used it quite often (did not have a GPS) with the Ley maps, and it worked fine. The Ley maps have an English scale printed on them, so you don't need one on your compass. And echoing others, you definitely need to pay attention to declination on the CDT--it will change substantially during the course of your hike, especially in the North. The Ley maps version I used did not show declination. I carried a chart. I did not use the other items you mentioned. I used the compass mainly on off-trail sections of the CDT to check heading, to orient the map at junctions and road crossings, etc. I never needed to triangulate on the CDT, but I have done that with the same compass on other trips. It's pretty rough without a sighting mirror, but rough is usually OK for hiking. It's not like you're calling in an artillery strike.
NeanderJoel
10-05-2012, 20:29
Okay thanks guys, I'll probably just get a cheapish compass from REI when I get there then. It sounds like it's not as difficult as I thought it may be, but then it's different for everybody I guess.
Interesting "science alerts" by the way. I believe some breeds of ants use the magnetic field to find their way back to the nest, too. Now I'm off to get lost in the woods!
Always carry a deck of cards! You know what they say:
"If you ever get lost in the woods just start playing Solitaire and before long someone will come along and tell you to play the Jack of Hearts on your Queen of Clubs"....... :)
NeanderJoel
10-06-2012, 05:47
Haha I'll put one in my "in case of emergency" kit
NeanderJoel
10-06-2012, 05:48
I only got lost enough to need my GPS once. I call it a good day :) Quite lucky actually, because as soon as I turned it on it said "low battery"
SunnyWalker
10-06-2012, 22:27
Silva Ranger compass. It seems that many CDT hikers confess to spending 1-2 hrs., each day trying to figure out ether where they are or where they are going. That is to me a sigificant amt of time to waste. Maybe a better compass, with declination adjustment would help out?
For those of us who are not orienteers, the compass built into the iPhone suffices just fine. It's fine if you just want to check your direction occasionally, and, the magnetic declination is automatic, based on your current location.
If you are carrying a phone anyway, this compass is zero additional weight.
Sent from my iPhone using Tapatalk
StubbleJumper
10-08-2012, 10:03
For those of us who are not orienteers, the compass built into the iPhone suffices just fine. It's fine if you just want to check your direction occasionally, and, the magnetic declination is automatic, based on your current location.
If you are carrying a phone anyway, this compass is zero additional weight.
Sent from my iPhone using Tapatalk
I've used my Android compass, and it's true that it works prfectly fine. However, I get a little bit of a funny feeling relying solely on electronics for navigation. Last summer I actually lost my compass when navigating to a backcountry shelter where there was no trail. It was very disconcerting to be miles from the nearest town with no obvious trail and have only a cell-phone to find the route. If the battery died or there were some other problem with the phone...
Happily enough, after spending the night at the shelter, I backtracked a quarter-mile and found my compass laying on the ground beside a rock where I had sat down to study my map. It was exactly where I carelessly left it! I was quite happy to collect my my $7 Silva and wander on down the trail.
Interestingly enough, I am not a technology Luddite. I used my Android a great deal while hiking, and in particular the AlpineQuest app and downloadable topo maps. When you are not on a marked trail and hike in mist, or if you are in a "featureless" landscape it's really great to get a GPS reading and see yourself positioned on the topo map. But I just can bring myself to rely only on that for navigation!
bearcreek
10-09-2012, 11:23
I strongly suggest carrying both a gps and a compass. As you hike, you will develop a preference for the tool you want to use for primary navigation.
Be wary of declinations printed on maps. Declinations are not a fixed value, but change slowly over time. Many of the topographic maps are old enough that the declinations printed on them are over three degrees out at this point in time. A correct value can be determined with a gps or smartphone gps app, (also printed on every Mapbook page) so that may be a reason to carry one of those, even if you don't use it very often.
Historically, there have been places where compasses work better than recreational grade gps. There are also places where a compass will not work reliably at all. The volcanic Malpais in NM is a great example of this. The Zuni-Acoma trail is like hiking through a giant magnet, and while compasses are worthless there, gps works fine.
Recently, Garmin has started making inexpensive Etrex receivers which utilize technology previously available only in expensive professional gear. The new units use both the US and Russian satellites simultaneously, doubling the number of geometric possibilities, and making gps work in many places it didn't before. Our professional mapping gear has this capability, and it works virtually everywhere, under heavy tree cover and in highly obstructed environments like deep canyons and steep hillsides. While the Garmins are not nearly as accurate, they are plenty accurate enough to follow a trail.
Spirit Walker
10-09-2012, 22:09
We didn't carry a gps on the CDT on either hike - never needed one. We only attempted to triangulate once - when we were looking for a well that was supposed to be on the road we were following and wanted to know whether we had passed it already. We figured out where we were and soon discovered the well had been demolished.
Otherwise we used the compass mostly to check whether the trail or road we were on was heading in the right direction. Sometimes a jeep road will have numerous side roads off it, none labeled. You know you're supposed to head off on a road that goes southeast. If you take a road and it starts heading in the wrong direction, perhaps you took the road 100 yards too soon. That happened to us a couple of times. Same thing with unmarked trails. You see blazes - but are they for the CDT or for another trail? Where is it heading? You don't need a fancy compass for that, or even great orienteering ability, just the ability to read a map and compass.
The times we got lost on the trail were almost always because we were going through a bad burn (Wagontongue Mtn. comes to mind) or when the trail was buried in snow. Map reading ability is what got us through. We did spend a lot of time keeping track of where we were. You need to pay attention to your maps, much more so than the AT or PCT. It's part of the experience. Having a gps probably gives you reassurance that you are where you think you are, but hopefully it's not telling you anything you don't already know.
I just saw a friend who hiked the CDT this past year. The CDT is a lot easier to hike than in terms of navigation challenges even from five years ago. (This is her second CDT hike)
She spoked highly of the Bear Creek maps and cherry picking Ley routes for such places as The Winds.
Seems like that is the trend now for CDT hiking: Easier route finding and relying mainly on Bear Creek maps with select JLey alternates.
handlebar
10-10-2012, 20:38
I'd take both a compass and a GPS. I'd load the GPS waypoints form Bear Creek Survey's web site into the GPS. I'd also consider taking the Bear Creek Maps, though they don't have the alternates (including the Lower/Upper Gila River route, the Gila Cliff Dwellings, and lots of alternate routes in the Winds and the Bob Marshall Wilderness. Nor do they have the excellent notes representing years of hikers' experiences that Jonathan Ley adds to his maps. I used both the Ley maps in '10,'11 and added the Bear Creek maps in '12.