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O-ring
- maintenance
by
Mike Maloney
Reproduced
from in focus 72 (October
2001)
There
are no set rules when it comes to the maintenance of underwater
equipment. Everyone does what they think is best and if their
methods work all well and good. If they don't the outcome
can be expensive so, over the years on many trips on liveaboards
and at shore-based sites, I have carefully watched how other
underwater photographers set up their camera equipment before
diving and how they maintain it.
Approaches
range from the really fastidious types who even take a magnifying
glass to check there are not hairs or grains of sand on their
O-rings to the really casual ones who just give a fleeting
glance at their O-rings before they slap everything together.
Surprisingly, both systems seem to work for them although
I know which one I prefer!
Others
grease their O-rings before a trip and that is that untiI
they return. Not to be recommended in my view. Some take out
the main 0-rings when they travel. This is all well and good
but great caution is needed when you re-assemble your equipment
after a flight of six or seven hours duration, or even longer.
If you are jet-lagged and tired it is so easy to forget to
refit the main O-ring before you enter the water, with disastrous
results.
Though
they might always be extremely fussy about their preparations,
a disaster can be the outcome of tiredness and lack of concentration
after a long flight. So my golden rule is always to be careful
and avoid rushing your preparations for that first dive with
a camera. Indeed, I always do my first dive without a camera
so I can concentrate on checking that my weight and buoyancy
are correct and that all my diving equipment is functioning
correctly. Also, I have time to once again adapt to being
in the sea. Remember, it might be your first dive for a long
time.
As
far as my Subal housing is concerned, I always remove the
main 0-ring before a flight and also for storage at home.
I keep it in a plastic bag inside the housing ready for assembly
and also as a reminder to replace it before I dive. This way
the O-ring does not take up a set shape and also is not squashed
and deformed by any pressure.
I
remove the back plate O-ring every time I open the housing.
Then I thoroughly clean and lightly re-grease it. I always
clean the O-ring groove, using toilet tissue. I only use the
cheaper type because it does not leave any fibres, unlike
the expensive, extra soft luxurious brands. My wife Jan always
uses pure linen tea clothes to clean her equipment and that
works for her. I never use cotton buds because I find they
also leave fibres, which is not what you want. Other people
run their 0-rings through their lips to clean off any hairs,
etc before they regrease them.
Other
accessible O-rings also require careful attention. Each time
I change a port I clean both the O-ring and the seating. If
you look at these rings carefully you will be surprised just
how much in the way of fine sand particles can gather on them
during just one dive, These fine grains are always present
in suspension in the sea and seem to be attracted to O-rings.
On
flights I do not remove the O-rings on the battery covers
of strobes. However, I slightly open them and secure the covers
in place with a strong elastic bond round the housing. Then
there's no chance of forgetting to refit them.
At
the start of a dive trip I always clean the seating and the
O-ring of my Y5120 strobe, fit my eight lithium batteries
and leave it in place until I need to change the batteries.
Blue
O-rings are now fitted to all Sea and Sea units. They seem
to become rather tight in the seating before removal. Indeed,
they almost cling when you leave them in place for say a week's
diving and photography. However, as the lith batteries have
such a long life you may feel more comfortable if you remove
the O-rings halfway through and clean and grease them before
refitting the cover.
Careful
attention needs to be given to the sync cord connections into
the camera housing. I clean and grease them at the start of
a trip then, if all works correctly, I leave them in place
until it is time to strip everything down for the return home.
Before assembly, I always make sure the sync plugs and their
threads are clean and greased. Also, I lightly grease the
shafts of the plugs into which the cables are inserted. If
you do not do this they can seize, no matter how many times
you rinse the unit in fresh water after each dive.
AI
I my general observations refer to my method of caring for
my Subal housing. Those relating to the strobes and sync cords
apply to both Subal and Nikonos V connections as they are
similar.
When I use my Nikonos, I clean and prepare the O-rings in
the same way and use the same materials. However, when I fly
I do not remove the main O-ring. Instead, I just release the
back so the air pressures can equalise and hold it in place
with a rubber band. Again, this is a way of ensuring I do
not forget to replace the back.
A
point which Peter Rowlands always stresses - he is an authorised
Nikonos service agent - is that when changing fiIms you should
always open the back with it facing downwards to stop any
tiny droplets of water caught between the 0-ring and the back
dropping into the main body or onto the delicate shutter blades,
causing untold damage.
When
I return home I reassemble all my equipment, clean all the
0-rings and seatings as I go along and then let them soak
in fresh water for a couple of days. This includes the strobes
as well as the housings and Nik V. While all the salt crystals
are soaking off it is a good idea to work all the controls
a few times while the equipment is in the water. This helps
free the salt deposits which always build up even though some
might be minute. They are the biggest enemy and must be washed
off.
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