I agree with Jonno on his post about the 17mm socket being used is a safe way to arm and dis-arm the robot's. This year was the first time that we had a few feathers using this method and it did make things easier and less worrying when deactivating them. There was just one issue where the bottle had moved and so all the gas needed to be dumped as the bottle couldnt be closed. However, that could happen to any bottle.

I take John lear's point about opening the bottle slowly and all it will do is raise the flipper slowly. That has happened a few times before and there's no issue with that. The issue arises when things happen that cause valves to fire and fire quickly. we get this the most at our event's, and having a locking bar stops this becoming an issue so I feel that it's most certainly required.

Craig, originally the rules used to state that any moving weapons required a locking bar. However when more electric lifter's and crushers started coming in things were changed as they weren't really required. For example Tiberius or kan-opener would probably need a huge I-beam to stop them from crushing, and once pressure is applied you cant always release it!

I think it's only a concern for very fast moving weapons. Kan-opener had the right idea with having a thin metal tube that popped into the jaws that could be bent easily if the claws closed, but kept people away from walking inside them!