PF Excavator
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Specifications:
- (body) - 27 studs long x 29 studs wide
- 2 x XL PF Motor
- 3 x PF Motor
- 2 x PF Battery Pack
- 2 x Pneumatic Actuators
- 2 x compressor pumps (feeding one output)
- Build time: approx. 14-16 hrs

Details:
One battery pack and iR receiver control the two XL Motors on the base that drive the
tracks. This was done so that no wires fed up to the upper body that could tangle. This
results in a full 360 degree rotation capability.

The upper body contains a regular PF motor that rotates the upper body, a regular PF
motor that drives a compressor (which uses 2 compressor pumps) to power the pneumatic
actuators. The two red switches in the centre of the upper body control the output.

The final regular PF motor on board drives the only non-lego part that raises and lowers
the base of the arm. This works in the same way that the new official Lego actuators do,
however the screw mechanism is visible. A hole was drilled into the end of the screw shaft
and a technic axle glued in. The receiving nut is a lego engine piston housing with a
threaded nylon cylinder glued inside. This results in a very powerful mechanism.
Unfortunately, this does not have the failsafe of the new actuators, so care must be taken
to not overdrive them.


Video coming soon.... :)