British watch maker Elliot Brown have just announced
the outcome of a unique six month ordeal that they put one of their watches
through. A £550 Bloxworth 929—007 watch was submerged at the bottom of Poole harbour
for half a year to simulate the kind of stresses an average wrist-based timepiece
would go through over 12 years of everyday use. The results... startling.
Find out more at www.elliotbrownwatches.com
Want to know why Elliot Brown watches are
the mutt's nuts? Check out these testing facts about what goes into every watch:
Crystals:
a 16.5g ball bearing is dropped from half a metre above the glass three
times to check it’s hardened and tempered correctly.
Pushers:
Each pusher is pressed 5,000 times to simulate years of wear and tear. They
must function perfectly after the test and feel the same when pressed – no
stiffer, no looser.
Strapping:
The ends of the leather straps are clamped down and the strap is flexed
in half then stretched out 5,000 times to ensure the leather won’t crack. A 1kg block pressing on a felt pad is dragged
backwards and forwards across the surface 150 times dry and 150 times soaked in
water to ensure there’s no loss of colour. Every type of strap in the range
(leather, bracelet, webbing, canvas) is subjected to a traction and torsion
test – a 5kg weight is hung from one end of the strap whilst the other end is
repeatedly twisted back and forth through 180 degrees 5,000 times.
Water-resistance: Every watch case is
pressure-tested in air to 75% of the stated water-resistance - 150m or 15 bar -
when they are manufactured. Air-pressure
is used instead of water because it’s non-destructive and faster than
water-testing. After the watches have been fully assembled, they are pressure-tested
again to 150m in air to make sure they’re able to withstand full ‘wet’
pressure-testing. Pressure testing watches individually is time-consuming and
expensive, which is why brands often only test a few watches from each batch.
Every completed watch is then wet
pressure-tested in a 30cm-deep steel pressure vessel of water to 20 bar/200m
for 10 min, and then placed on a hot-plate at 40-45c for 15 minutes. A drop of water between 18 and 25c is placed
on the glass, and after a minute, the watches are wiped dry and checked for
condensation under the crystal which highlights any leaks.
Shock-resistance: A percentage of every batch is tested for
shock-resistance by striking them twice with a 3kg pendulum hammer - once on
the left-hand side of the case and once on the crystal, which simulates the
impact the watch sustains if it falls from 1m onto a hardwood floor. As an additional real-world test, a selection
of watches from every batch is dropped 4 times in succession from a metre onto
a hardwood surface.
Timekeeping: The assembled watches are put through a
’burn-test’ for 24 hours in 4 positions – face-up, face-down, crown-up, and
crown-down, to test for timekeeping issues.