[Coral-List] Underwater Drill
georg.heiss at reefcheck.de
Tue Feb 20 10:32:21 EST 2007
we used hand-held pneumatic drills with great
success. See below excerpt from a publication of
With some care we could use them for years: run
the drill after use with air to remove salt
water, soak in fresh water, clean again with air,
then put oil everywhere inside the drill and run
it briefly to distribute the oil inside the
All material is standard toolshop stuff, except
the drill barrel, which is also standard, used
mostly for drilling holes in walls for
For photos, see
(lower part of the page). I can also send a photo
of the drill and drill bit in higher resolution.
Heiss, G.A., Dullo, W.-Chr. and Reijmer, J.J.G.
(1993): Short- and long-term growth history of
massive Porites sp. from Aqaba (Red Sea).-
Senckenbergiana maritima, 23/4/6: 135-141.
Materials and Methods
Several attempts of underwater coring are
recorded in the history of coral reef research.
The dimension of the operations as well as the
means used vary.
After the early rude method of blasting reef
sections, hydraulic submersible drills have
widely been used with great success (MACINTYRE
1975; HUDSON ET AL. 1976; HUDSON 1977; DRUFFEL &
LINICK 1978; HUDSON 1981; MACINTYRE ET AL. 1981;
DRUFFEL 1982; SCHNEIDER & SMITH 1982; ISDALE
1984; BARNES & LOUGH 1989; WINTER ET AL. 1991;
BURKE ET AL. ?).
The first drill for underwater coring driven by
pressured air is described 1975 at Lizard Island,
Great Barrier Reef (DAVIES & STEWART 1976) but as
far as we know, no study on cores obtained with
this drill has been published. In contrast to
their drill we didn't use an impact tool and we
could work independently from a boat. Further
attempts were made by (STEARN & COLASSIN 1983)
who gave a description of an underwater pneumatic
hand drill. (POTTS ET AL. 1985) took short cores
(10-15 cm long) of Porites with a hole saw welded
to a 30 cm pipe and mounted in a pneumatic drill.
At Curaçao the growth rates of Montastrea
annularis were recently studied on cores taken by
a pneumatic drill similar to our equipment
The intention was to build a simple, cheap and
small coring tool, which can be operated by one
Scuba-diver independent from any supply on the
sea-surface. We wanted to avoid some
disadvantages of the already described machines
for our field work as there are the large size of
some and therefore the limited mobility and/or
the need of energy support from a boat. A
technique for gaining long coral cores with a
handy instrument has been developed.
Besides sampling of several smaller individual
colonies over the depth range to 45 m (HEISS in
prep.) we wanted to get records on growth rate
and proxy dates over a longer period. Another
important objective was the possibility of
comparing with other long-term growth records in
corals in other localities of the world. In the
last 20 years several successful attempts of
large scale coring in living corals have been
made (MACINTYRE 1975; HUDSON ET AL. 1976; DRUFFEL
& LINICK 1978; MACINTYRE 1978; HUDSON 1981;
DRUFFEL 1982; ISDALE 1984).
Due to the availability of Scuba-tanks and the
need for easy handling from small boats we chose
compressed air as the best power source for the
drill. A commercially available RODCRAFT
4200-pneumatic drill was selected on the basis of
its size and technical characteristics. It works
at a speed of 2000 rpm with an air consumption of
220 l/min under full power. Although the
operating pressure is 0.6 MPa (6 bar,
manufacturer's information), we operated the
drill at a pressure of 8-9 bar which is the
pressure supplied by an ordinary first stage
regulator for Scuba-diving. We used in the first
year a SCUBAPRO Mark II first stage. We later
improved the system by using a balanced first
stage (SCUBAPRO Mark X) in order to have a better
air supply in water depths greater than 10m. The
air came from 15 l dive tanks, pressurized to 200
bar, which provides an air capacity of 3000 l.
The connection between tank and drill was a
standard industrial pressure hose of 2 m length.
The core-cutter is a diamond-tipped steel tube of
300 mm length and an outside diameter of 41 mm
(36 mm inside) manufactured by DIA-G
Diamantwerkzeuge GmbH, Kiel.
With this composition of the instrument we could
easily obtain cores of 30 cm length from
different massive growing genera like Platygyra,
Porites, Hydnophora, Favia and Favites.
The initial millimeters were drilled by turning
the core barrel by hand several times on the
coral surface. No template was necessary for the
drilling procedure. Drilling of one 30 cm core
took only a few minutes. Depending on the
rigidity of the coral we could obtain up to four
cores out of one 15l-tank.
At 13:25 Uhr +0000 14.02.2007, aj.martignette at comcast.net wrote:
>I have to drill some holes in pilings for large
>bolts that will be used to mount water quality
>sensors. I would like to avoid having to drill
>them with a hand drill. I know that you can use
>a pneumatic drill hooked up to a scuba tank. I
>was wondering if anyone had details on a setup
>they use and any modifications that are needed
>to the drill.
>Sanibel-Captiva Conservation Foundation
>900A Tarpon Bay Rd.
>Sanibel, Fl 33957
More information about the Coral-List