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Will compasses keep you on track? Land navigation is an essential skill to learn for wilderness survival. Therefore, the compass is a critical part of successful land navigation. People navigated by the stars, dead reckoning, and terrain association before the invention of the compass or the nautical sextant astrolabe. There are many kinds of compasses available to the modern outdoorsman. Compasses fall into two categories based on the method of needle stabilization, also known as damping: liquid-filled and magnetic induction. Thus, purchasing a quality compass for use in the field is as important as having an accurate topographic map.

1. Liquid-filled Compasses

 

The most common type of compass on the commercial market are those with liquid damping. Liquid damping is the method of stabilizing needle movement by immersing it in an enclosed, liquid-filled housing chamber. Several types of liquid are in use for this method. Mineral oil, kerosene, or ethyl alcohol are the most common. Minimizing needle movement in a compass ensures maintaining a direction while trekking over land. An example of a liquid-filled compass is the Suunto Clipper Wrist Compass or the Suunto M3 Baseplate Compass. A quality liquid-filled compass is an excellent option for those who enjoy the outdoors recreationally or you are living in an urban-suburban survival zone.

Advantages:

The advantage of a liquid-filled compass is the retail cost to the consumer. Many of the budget-friendly compasses on the market are those that have liquid damping. Commercial button and wrist compasses use the liquid dampening method for needle stabilization. Therefore, compasses manufactured with this dampening method make them accessible to the average consumer. Examples of budget-friendly compasses using liquid-filled dampening are those by Coghlan’s and Coleman.

Disadvantages:

A disadvantage of compasses with liquid damping is that the liquid can form bubbles. These bubbles can affect compass accuracy. Another problem with these kinds of compasses is that the liquid can thicken in arctic temperatures. Consequently, the thickened oil restricts needle movement. This characteristic of oil-filled compasses limits there use to non-military applications. Moreover, the high temperatures in the summer in arid environments can cause the liquid to expand or evaporate. Consequently, if the housing becomes cracked, the liquid will leak out. Thus, the compass becomes inoperable.

2. Magnetic Induction Damping Compasses

 

Compasses using magnetic induction damping are the second most common compasses available to the outdoorsman. A compass utilizing magnetic induction is one in which the needle is stabilized through a magnetized field created within the needle housing. The most common way that this happens is by a magnet passing through an electromagnetic field.

However, magnetic induction damping in a typical lensatic compass occurs when the magnetized needle is moving through a copper needle housing. The U.S. Army M-1950 lensatic compass is an example of this kind of compass. Magnetic induction damping compasses are the preference of most militaries around the world.

Advantages

The significant advantage of a compass using magnetic induction damping over liquid damping is its use in extreme temperatures. The compass with magnetic damping is usable in extreme arctic and extreme tropical or desert environments. The absence of the liquid in the needle housing eliminates the concern over the liquid freezing or expanding due to extreme temperatures.

Another advantage of these kinds of compasses is they tend to give a more accurate and stable reading when shooting an azimuth. The stability of the needle enables their use for land navigation in both night and day situations. Most military compasses copy the lensatic sighting mirror compasses first introduced by the British on the eve of the twentieth century. You can learn more about the U.S. Army lensatic compass in my article, “A Short History of the U. S. Army M-1950 Lensatic Compass.”

Disadvantages

A disadvantage with compasses that have magnetic induction damping is that they can be more expensive to the average consumer. The process that creates the magnetic induction damping feature of the compass is more complicated than merely filling the needle housing with liquid. Furthermore, the compass housings must be of metal construction for the magnetic damping to work. Consequently, the cost increases to manufacture these compasses.

The second disadvantage of a compass using magnetic induction damping is that it can be complicated to use. For example, complaints often heard against the U.S. Army’s lensatic compass is that it is hard to use to take an azimuth and for land navigation. By contrast, those trained and experienced with these compasses use them as well as a person favoring the Suunto MC-2 Compass. Furthermore, the U.S. Army lensatic compass was designed to meet the specific needs and standards of the military and for military operations. They were not designed for use to survive the apocalypse, SHTF, or grid-down scenarios. Therefore, it is understandable why there are complaints about lensatic compasses.

Final Thoughts

A quality compass is a must-have item in the packing lists of your various bags. The two most common types of compasses are the liquid-filled and those using magnetic induction damping. Additionally, the compass that you adopt is one that should be accurate, durable, and magnetized for the proper hemisphere. You do not want to stake your life on a compass of lower quality.

Most survival experts advise spending money on a good fixed-blade knife. The same recommendation is valid for the purchase of your compass. Furthermore, if you are a world traveler, there are quality compasses available for use in both the northern and southern hemispheres. Suunto and Brunton have compasses that meet this need. A quality compass is an instrument that will enable your survival should you get lost on the trail or the backcountry. Therefore, choose your compass wisely and deliberately.

The best compasses for your kit considerations are those of proven quality, durability, and accuracy. The compass that you choose to include in any level of survival or outdoor packing list is one of the essential items in your loadout. As well, there are strong feelings among many about what brand or type of compass is the best on the market. However, the best compass on the market is the one that you have used and are the most confident with when you are in the field. However, the best compasses for your kit are the following:

1. U. S. Army Lensatic Compass

The U. S. Army Lensatic Compass conforms to the military standards published in MIL-PRF-10436N. Also, the military lensatic compasses are made in the United States. The current manufacturer of this compass is the Cammenga Company in Dearborn, Michigan. Of note, the previous maker of these compasses is Stocker & Yale, Incorporated in Beverly, Massachusetts. For example, the two lensatic compasses that I own are from Stocker & Yale. Moreover, you can purchase one of these Cammenga military lensatic compasses at the Sigma 3 Survival Store.

Description:

A lensatic compass is a magnetic compass that uses a magnifying glass to read its scale or dial. The U. S. Army lensatic compass is an induction-damped, handheld, north-seeking instrument with an internal, self-exciting light source, in other words, it is self-illuminating (tritium or phosphorous). The baseplate construction is of high-grade aluminum with a powder coating. The needle moves within a non-liquid filled needle housing. Thus, the military lensatic compass is one of the best overall compasses on the market.

Features:

Cammenga makes this compass with two options: model 3H with a tritium luminous dial (NSN: 6605-01-196-6971) or model 27 with a phosphorous luminescent dial (NSN: 6605-01-571-6052). Interestingly, Cammenga produces these compasses in the following colors: Olive Drab, RealTree® Camo, Black, and Coyote Brown. The compasses have a free-floating needle instead of the needle floating in a liquid (water or oil). They are also waterproof and dustproof under most field conditions. They will function in temperatures between -50°F (-46°C) and 150°F (66°C). The compass is also shockproof is dropped from up to three feet (90 cm). Additionally, they also have two needle options: Northern Hemisphere and Southern Hemisphere.

Additional Comments:

Moreover, the lensatic compass is the standard compass in all my backpack load outs. I have other compasses, but my U. S. Army lensatic compass is the one that I keep coming back to when I need reliability, durability, and accuracy. Most of all, I do not have to wait for satellite synchronization or linkage with the lensatic compass. There are no extra batteries that need to be carried in a pack because it is an analog magnetic compass. In addition to these features, the military lensatic compass also fits comfortably into the LC-2 ALICE First Aid Pouch or the MOLLE Grenade Pouch.

Best Uses:

Advanced and Tactical Day and Night land navigation
Orienteering
Hiking & Backpacking
Game Hunting

2. K&R Alpin Sighting Compass

The next type of compass that can be part of your loadout is the mirrored sighting compass. One of the best on the market is the K&R Alpin Sighting Compass. The compass is a product based on input from the German Mountain Rescue Service. These compasses are made in Germany.

Overview:

A mirrored sighting compass is a compass in which the compass dial can be viewed using a mirror while simultaneously sighting an object through the sighing notch or slot on the compass lid. That is why these kinds of compasses are not in the category of being a lensatic compass. The sighting compass is sometimes called the hand compass, forester compass, or cruiser compass. They are one-hand use compasses. Their easy use quickly found them being a favorite of the geology, marine, and forestry professions.

Features:

The Alpin Sighting Compass has several convenient features. The sighting mirror is polished stainless steel. The baseplate, compass lid, and compass capsule are made of high-impact plastic. The result is a compass that is very durable and lightweight. The needle moves within a liquid filled needle housing. The bezel is self-luminating with two large sighting notches (12 and 6 o’clock positions) on the bezel for night navigation. It also has a clinometer to measure incline while traversing uneven or mountainous terrain. K&R has three measurement options for this compass: standard, metric, and mils.

Additional Observations:

This particular compass is an excellent alternative to the military lensatic compass. The large glowing bezel makes it user-friendly for trekking at night. It is easy to use and probably a better option for those unfamiliar with using the military lensatic compass. A rival to the Alpin is the Suunto MC-2 Sighting Compass. Both of these compasses fit comfortably into the MOLLE Gen II Flashbang Grenade Pouch. The K&R Alpin and the Suunto MC-2 compasses represent the best of the mirrored sighting compasses on the market.

Best Uses:

Advanced Land Navigation
Orienteering
Hiking and Backpacking
Game Hunting
Emergency Preparedness

3. Suunto M-3 G Compass

Finally, a third type of compass option for your outdoor activity concerns is the simple baseplate compass. The baseplate compass is the most common type on the market. One can purchase these kinds of compasses with various levels of quality and in various price ranges. The primary use for the baseplate compass is in conjunction with a map.

Description:

Baseplate compasses have a clear plastic base upon which the compass mechanism sits. The sides of the baseplate usually are marked in standard increments. These markings allow the baseplate to function as a ruler for measuring distances on the map. The baseplate also has a magnifying glass embedded for observing small map details. The needle mechanism usually is liquid filled and jewel bearing.

Features:

The Suunto M-3 G Compass has several useful characteristics. The bezel is luminescent. The G model has a globally aligned needle so it can be used anywhere on the earth in both hemispheres. This model also comes in just a northern hemisphere (NH) needle orientation and a southern hemisphere (SH) needle orientation. It is incrementally marked in metric and imperial UTM scales. The compass also has a clinometer for determining the slope of an incline. This compass originates in Finland

Additional Observations:

The baseplate compass is one of the most versatile compasses that one can own. The Suunto M-3 compasses offer the basic navigational needs for most scenarios and applications. They are small enough to fit easily into a MOLLE Flashbang Grenade Pouch. They come with a lanyard which allows attachment to the shoulder strap of most backpacks. These compasses are easy to use and are an excellent option for the occasional outdoorsman or weekend hiker or backpacker.

Best Uses:

General Land Navigation
Hiking and Backpacking
Game Hunting
Emergency Preparations

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