Compass

[sandbender]

Hello, BCUK. Which compass should I purchase? I know that I need a baseplate compass and know the general features. For some reason, the one recommended in The Ultimate Navigation Manual, the Suunto M3 Global, isn't available on Amazon.co.uk. Well, there's one available but it's vastly overpriced. Curious. Are Silva good? What compass do you use?

Where will you need to use it?

For most a Silva 4 is all they will ever need, I have some posher Silva's they have more scales perhaps and the adjustment for deviation mentioned earlier but you do not really need those, being able to navigate is mostly about what is in your head than how gucci your compass is.

 

[wingstoo]

http://www2.ca.uky.edu/Forestry/FOR250/Compass.pdf

2. Permanent Method. Your compass is equipped with an offsetting mechanism to
allow for declination. If you use the compass extensively in one locality, once set,
you need not make further allowances. The adjustment simultaneously takes care
of both map bearings and field bearings.
The offsetting mechanism consists of two bottoms in the compass dial housing,
one of which can be offset in relation to the other by means of a declination
adjusting screw located on the underside of the base plate. The orienting lines
and the declination scale are engraved on one bottom. The orienting arrow
and the orienting points are on the other. As you turn the adjusting screw you
change the angle between the orienting lines and the orienting arrow. It is this
angle that should correspond to the declination of your area. A screwdriver, provided
for this purpose, is tied onto the lanyard.
For example, if the declination in your area is 10º west, turn the adjusting screw
so that the orienting arrow points to 10º on the “west” side of the declination
scale. If your declination is 10º east, adjust the orienting arrow to 10º on the
“east” side of the declination scale. Use the black index line of the orienting
arrow to make an accurate setting.

 

[greensurfingbear]

I use the silva expedition four. Had it for over 10 years. Spot on piece of kit. Mind you mines developed a bubble in the housing...... it disappears when the compass is warm but comes back if it gets cold.....think its time for a replacement.....was thinking of going for a one of the Silva sighting compasses

 

[Headshed]

Another vote for the Silva, I use an expedition 54, as I find the roamer scale useful for grid refs. Although to be fair I always have a Garmin GPS 60 along as well (used for grid location only). For most navigation purposes though, night and bad weather excepted, I usually don't worry about setting grid to mag or mag to grid as I can see my hand rails or target and use the compass to align my direction of travel and then rely on map features.

 

[Tiley]

I've used Silva for nearly the whole of my time outdoors but I bought a Suunto Global compass when fun 'n' games took me to New Zealand. The M3 is just a better product - a bit easier to use and read than the Silva and seemingly better made - and now goes with me everywhere.

 

[Jonbodthethird]

I've got a silva and it works perfectly good enough for the average bushcrafter.


Sent from my iPhone using Tapatalk

 

[Uilleachan]

Te model on mine iss printed along the bottom edge

Yes, just taken a look, mines is a "Type 4/54" although it's marked behind the bezel on the top rather than the edge. Handy tool.

 

[THOaken]

Isn't it that a compass points to magnetic North, but maps point to grid north? And you have to compensate for magnetic declination in your country as it changes every year. I'm currently reading the Ultimate Navigation Manual. My Silva 4 came today.

 

[THOaken]

I have to admit that this is my first time ever purchasing, in fact using a compass. Well, I may have used a compass when I was much younger. I have been going outdoors for about 2 and a half to 3 years now, and that includes wild places like Beinn Eighe and walking off the tracks in Abernethy Forest and such places. I never felt the need to buy a compass and that everywhere else I went I just needed to follow trails. I've never really gotten lost, but I'm planning to go walking by myself in the future for some distance and I think it's time to read up on navigation. In fact compasses weren't even on my mind until I started to think about navigation in the past week. Just for reassurance, is there anyone else who felt this way?

 

[Chilliphil]

A compass is only of use to you if you know how to use it and how to use it with a map. I always carry one with me, but rarely use it unless I'm somewhere unfamiliar and need to confirm my location. Used correctly with a good scale OS map it is an excellent tool. Well done to you for reading up on it, I find maps and navigation a fascinating subject. Just remember to get your bearings right, a bearing slightly out by a few degrees in a miles time is a long way off your track!!

 

[Goatboy]

Hi THOaken,

In reply to your last two posts there are a few different "Norths" True, Magnetic and Grid north. Yup the compass points to magnetic, and most folk for general navigation in good visibility don't correct for declination (which yes shifts over time) but if your navigating over distance, featurless terrain and/or poor visibility then declination is important. Some compasses have a small adjustment screw which allows you to dial in the declination so taking the mental adjustment out of the equation.

On the bothering to use a compass well I too have a good sense of direction and use other tricks and tips to avoid getting lost, but I do carry a compass as it's sods law that I'd get lost somewhere silly. And it's good to keep the skills brushed up. When I started using and selling GPS a number of years back I became lazy but soon realised that one can't rely on something that runs on batteries. So went back and brushed my skills up all over again. Which I'm doing again at the moment as I've been asked to teach a wee navigation course later in the year. It's fun though and always a good skill to keep sharp.

 

[Uilleachan]

Hi THOaken,

In reply to your last two posts there are a few different "Norths" True, Magnetic and Grid north. Yup the compass points to magnetic, and most folk for general navigation in good visibility don't correct for declination (which yes shifts over time) but if your navigating over distance, featurless terrain and/or poor visibility then declination is important. Some compasses have a small adjustment screw which allows you to dial in the declination so taking the mental adjustment out of the equation.

On the bothering to use a compass well I too have a good sense of direction and use other tricks and tips to avoid getting lost, but I do carry a compass as it's sods law that I'd get lost somewhere silly. And it's good to keep the skills brushed up. When I started using and selling GPS a number of years back I became lazy but soon realised that one can't rely on something that runs on batteries. So went back and brushed my skills up all over again. Which I'm doing again at the moment as I've been asked to teach a wee navigation course later in the year. It's fun though and always a good skill to keep sharp.

^^^^ What Goatboy said.

I'd only add to that to say, I too have done a bit of walking in rough places in my time and I seldom use a compass, that said though; if it's serious terrain, like Ben Eighe or more so Rannoch, the Gorms or getting off the top of the Ben, in whiteout/poor visibility, I always know where I am in relation to the map, just incase the cloud comes down and I need find my way off with the compass, which I have had to do on several occasions. So an occasional tool that can save ones life, or face as a minimum, not considered cool to have the MR called out unless your injured.

On your other nav thread I recommended Pete Cliff's "Mountain Navigation" £5 or £6 well spent in my opinion, as small and light as a map to carry and all you should ever need. Now you've got a compass, get the map out and work your way through Pete's wee book, knowing how fast you walk knowing the basics with map and compass is all worth knowing, if you plan going off track.

 

[THOaken]

Thanks, everyone.

So I've just started reading the exercises in the UNM book and the first lesson is how to orient the map. However I don't actually have any maps. I've tried looking for OS maps of Hampshire, but can't really find any. I'd really like to practice these skills as a beginner in woods such as Stansted Forest, Havant Thicket and Hollybanks wood where I live, but I'm not sure where to find them or if they even exist. I can't really do the exercises without maps.

 

[Uilleachan]

Thanks, everyone.

So I've just started reading the exercises in the UNM book and the first lesson is how to orient the map. However I don't actually have any maps. I've tried looking for OS maps of Hampshire, but can't really find any. I'd really like to practice these skills as a beginner in woods such as Stansted Forest, Havant Thicket and Hollybanks wood where I live, but I'm not sure where to find them or if they even exist. I can't really do the exercises without maps.

OS online: https://www.ordnancesurvey.co.uk/shop/maps.html?mapsearch=Hampshire&cat[0]=20

 

[Nohoval_Turrets]

Degrees are accurate enough for this type of compass. Without other tools, I don't think the greater implied accuracy of mills will apply. Degrees are about at the limit of accuracy for adjusting these bezels by sight, and I've never been able to blame a nav error on .25 degree error. Also, I find it easier to remember the values of the main points in degrees - very important in guessing the value before blindly following the compass reading. I can take bearings and back-bearings, and triangulate a position to enough accuracy for any need I can imagine. And I can't walk in a line even close to degree accuracy.

Choose whichever system you like the best. Most civvies choose degrees.

 

[santaman2000]

Thanks, everyone.

So I've just started reading the exercises in the UNM book and the first lesson is how to orient the map. However I don't actually have any maps. I've tried looking for OS maps of Hampshire, but can't really find any. I'd really like to practice these skills as a beginner in woods such as Stansted Forest, Havant Thicket and Hollybanks wood where I live, but I'm not sure where to find them or if they even exist. I can't really do the exercises without maps.

This book was the standard back in the days when I was a boy Scout www.thecompassstore>com/mapandcompass.htm It's still the best I've ever found. it has sections on navigating with compass alone, map alone, and with map and compass together. The author Bjorn Kjellstrom, was the original designer and of orienteering compasses (modern baseplate compasses) and the founder of the Silva company.

I'd also reccomend you try to find an orienteering club in your local area.

 

[santaman2000]

....Choose whichever system you like the best. Most civvies choose degrees.

Most, if not all, aviators do too. If it's accurate enough to fly thousands of miles, that should be more than accurate enough.

 

[EdS]

Next big question though will be mils or degrees? I have bought both types, mils is a lot more accurate measure than degrees having 6400mils in a full circle , but to be honest when on a compass it doesn't really make a lot of difference without the use of a mils protractor.

Mils isn't more accurate - yes it does break the increments down into small units but a Mils compass uses 6400 mils (or 6000 is Russian etc) per circle to make it easier for field use and a degrees compass uses 360degrees - there in lies a problem with Mils compasses. There are 6283 Milradians in a circles not 6400 so an error is introduced even before you start. For rough navigation you'd do with a hand held device it doesn't mean much but once you start using trigonometry you've got errors.

This doesn't happen with degrees.

Of course if you wanted to do it very accurately and mathematically correct - degrees and minutes works. Much finer increments as 60 seconds per degree, you can even add on seconds. Not that you'd be able to mark a compass up in degrees and seconds.

Mils are handy in that you only use one unit for compass and for use in recticles - they where orginally adopted by the military for artillery ranging ie distances rather than compass use.


Or you could use Gradians - probably the most accuarte

 

[Goatboy]

Yup the difference between degrees and mils is just that it's a different system really. You'll find on less expensive compasses that the degrees are in 5 degree increments (generally) and that the more comprehensive compasses that they are in smaller increments leading to greater accuracy. Learning to hold the compass level is a very important step as an off kilter compass can throw your readings off.

Peter Cliff's book is excellent, comprehensive and easy to understand. Which a lot of books aren't.

Knowing where you are on the map is a good habit to stay in as Uilleachan says. Even if I don't have a compass out I'll periodically be checking my position to the map. With time you don't rely on the compass to do this though a periodic double check is good practice. Learning to interpret the map properly is a good thing. Whether O.S., Harveys or some other. Get to know the symbols and what's a convex or concave slope. Makes life so much easier. The likes of Memory Map have a 3D function where the graphics and shading really help here. Also when mountain travelling in winter aids as to avalanche avoidance due to weather and slope severity. (Also makes life easier as it helps you cutting out loosing height unnecessarily due to poor route selection; I'd rather walk a little further along a contour than loose height gained in mountainous terrain).

If you do go down the route of printing out maps for use in the hills make sure you don't print off too small a section. This can be disastrous in certain terrains as if you get lots somewhere where it's relatively featureless or visibility is hindered then with a wee map you may not be able to triangulate your position - (so speaks the embarrassed voice of experience). Also on the triangulation front I carry a Silva protractor
to allow me to do so from objects far away on the map as you don't want to use a straight edge from a ferrous material like the back of a knife as it'll affect your compass needle. (Also keep radios, mobiles and magnetic jewellery away from your compass.)

Some great advice being posted up by folk, also worth a wee look here(LINK). It's aimed at kids but is a very simple clear way to grasp the basics. Some folk teach navigation as a black art, but it doesn't need to be. Silva's 1-2-3 step guide is fantastically simple and logical.

 

[THOaken]

I don't quite understand. I thought OS had maps of local areas. I thought I'd be able to get a map of Stansted Forest or some other place in detail and see all the contour lines and things so I could navigate my way through the forest. There isn't really any of that available. I've been looking at many different websites, some recommended here, but I can't find what I was looking for. Best I've been able to find is something like this.

I don't know how I'm supposed to be able to learn map and compass without a map of local areas. The only ones OS has is the New Forest. And other maps of local woods are too large in scale, if that's the right word.

Does any of that make sense? I'm trying to find maps that are "inside" the woods... because I already know how to get to them so a map like the one above is useless.