Trad Gear: Cams
Cams are reliable and versatile pieces of
trad protection that are designed to be
placed in parallel sided cracks, where nuts
won't work.
A cam has three or four lobes mounted on
an axle. Each lobe is shaped according to
a mathematical logarithmic spiral, so the
angle between the lobes and the rock is
always the same, no matter how retracted
the cam lobes are. This means that the
cam will work at any point of it's size range
(more on this later).
When a cam is weighted, the lobes are
forced apart, converting the downwards
force into a huge amount of outwards
pressure on the sides of the crack. It is this
outwards pressure which holds the cam in
place.
When you place a cam, its springs keep
the lobes pressing out on the sides of the
crack, creating just enough friction to keep
it in place. Because cams rely on this
friction to stay in position, make sure to
only place them in clean, dry cracks. Mud,
water or ice reduces the friction and can
cause the cam to slide out during a fall.
Learn more: www.vdiffclimbing.com
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