The most important part of AMPEX is the drill head. Its design is based on a common ice core drill head that is used e.g. by scientist for research in Antarctica.
The drill head consists of three main parts: The body, the cutters, the coredogs:
- The body is made of aluminium, has a diameter of 94 mm and allows us to drill an ice core with a diameter of 74 mm. In addition to numerous holes for screws, the body has two long grooves which remove the drilled ice.
- The three cutters are made of tool steel and are attached to the body with two screws. They cut themselves through the ice, which is led away over the grooves.
- The coredogs are needed to separate the drilled ice core from the ground. During the drilling process they will be pressed against the surface by the leaf springs. At the end of the drilling process the drill moves a few millimetres up and the coredogs anchor into the brittle ice. Further rotation of the drill scratches the ice core, so it easily breaks when exerting an upward force.
At the end we will disconnect the barrel from the motor and remove the ice core to hand it over to other scientists to perform examinations.
To avoid rotational or vertical motion it is necessary to anchor the experimental box on the glacier. The spikes are manufactured by ourselves in the Studiwerkstatt Aachen. They are connected to the aluminium nodes of the experimental box and consist of two main parts, the casing and the heating cartridge.
- The casing is made from a round bar of copper and processed on a lathe. It gets two millimetres grooves and a borehole to insert the heating cartridge. In addition, we drill two threads for grub screws and a hole for a locking bolt.
- At 380 W/mK, copper has the highest thermal conductivity among metals. Therefore, the heat from the heating cartridges is transferred very well to the ice, which then melts. Thanks to the grub screw there is a secure contact between the heating cartridge and the copper jacket.
During the heating process the experimental box will sink into the ice. Within one up to two minutes, the water will refreeze, so that the box is perfectly anchored to the glacier. First tests in the laboratory have confirmed and even exceeded our expectations!