Cheers guys. Ok, internals! as I mentioned the weapon is powered by a standard type 20kg servo through a couple of bars to push on the furthest forward of the lifters arms, and the drive is actually 4 metal gear micro servos at the moment. These turned out to be a pretty poor method, but at this stage I was really just aiming to get the thing mobile, and without the need for ESCs this was a nice simple solution, going straight into the receiver. They are actually quite a bit more robust than I expected, but the small shafts to attach the wheels to mean they probably wouldn't take much to break in battle. Here it is with the lifter arm removed (cable ties everywhere!):
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This means that it is all powered by one 6v 950mAh receiver battery, slotted into the rear bulkhead, although i have plans to upgrade the drive, as it is 200g+ under the weight still, and have a selection of bits already to try out when i get time
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