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Trail talk: how to use the sun clock on the Silva Ranger SL compass

The little Ranger SL sighting compass from Silva includes a sun clock that is simple to use.

Silva Ranger SL compass

The Silva Ranger SL (previously the Ranger 27) is a sweet little sighting compass weighing just 23 grams. Made almost entirely from plastic, the only metal parts are a brass hinge pin, the compass needle, a copper retainer for the compass housing and a safety pin, with which the opened compass can be pinned to the front of a jacket for quick direction checking glances. Closed, the compass measures 57mm x 40mm x 14mm. It can make an ideal lightweight backup compass, though is relied on by some as a primary compass. Accuracy is never going to be spot on with this little compass as bezel graduations are five degrees, though extrapolation can be achieved. For a primary compass, two degrees is the ideal. The 33mm x 28mm glass sighting mirror is also handy for first aid purposes and tick checks.

Closed Silva Ranger SL compass. At just 23cm, the lanyard is very short

A sundial, in it’s narrowest and truest meaning, incorporates a gnomon, that casts a shadow on a dial. This is not how the Silva sun clock operates, despite being described by Silva as a sundial. Silva have included a simple sun clock on the bottom of this little compass though it seems few have any idea on how to use it.

Sight toward the sun with the sighting notch on the top of the lid housing. Even on a partially cloudy day, the sun can frequently be seen through the clouds
With the lid closed to forty-five degrees, the compass needle can be seen in the mirror. Keeping the compass level and maintaining the direction in which the compass is pointing, rotate the compass housing until the compass needle is sitting in the red gate of the housing arrow in the centre of the orienting lines
Turn the compass over and read what time the red arrow on the compass housing is pointing toward. There is no need to orientate the compass at this point. The time here is thirty minutes past midday
On a bright clear day the sun can be precisely placed, take care!
On a clear day the sun can be precisely placed, take care!
The time here is 18.30 in the evening
Looking at the red arrow on the rotated compass housing, it can be seen that it is 18.30 in the evening

Note that daylight saving time is not taken into consideration and the time may have to be amended by an hour as a consequence.

Or look at your watch…

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