Yep, thats because I'm asleep

This is a valve buffer combination that I have been playing around with. http://robowars.org/forum/album_pic.php?pic_id=1505 It is the addition of a few ideas that others have posted.

I don't know what thickness each part should be to cope with the pressure and the impact. It is a 50 * 70 mm ram and 100 mm buffer. It is not drawn to scale.
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So even the rain that falls isn't actually going to fill our dams and our river systems

I can't comment about the valve, but the way you arranged the buffer around the cyclinder makes it extremely difficult to make. It would be easier and cheaper to make the cylinder a seperate part and bolt it to the buffer from the right hand end. The buffer would then be just a length of tube with minimal machining.

You could make it cheaper again by using the same construction as most commercial rams, with external tie rods between the end plates. This allows the buffer tube to be just thick enough cope with the pressure without having to be thick enough to be tapped at the ends.

Thanks for the input, Nick. I don't know what is hard to do as I have not done any machining.

Here are a couple of other drawings I have done. They are variations on a theme. http://robowars.org/forum/album_pic.php?pic_id=1506
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So even the rain that falls isn't actually going to fill our dams and our river systems

I am thinking of using the tracks from a Zig-zag remote control car. Does anyone know if these have been tried on a feather? I guess I would need to copy the plastic wheels with HDPE or aluminium.

Any thoughts?
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So even the rain that falls isn't actually going to fill our dams and our river systems

pretty sure Andrew (totally recycled) made a random ass robot from some drills and using modded red wheels as the wheels running some rubber tracks from an rc car, seemed to do alright, came off a few times but that can prob be ironed out with mods and such
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Andrew Welch, Team Unconventional Robotics

What would be the point of tracks, beside the coolness factor? They would weigh quite a bit and a good flipper doesn't need all that much pushing power. If you need more grip, a set of Jake's wheels would be a better buy.

tracks seem like a bad idea in general, they fall off and are only really going to help if your high sided and the point lifting you is actually under the track itself
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Mechanical engineers build weapons, civil engineers build targets

Yay, buy Anderson wheels!!! Ahem, seriously, I'd look at more speed and reasonable traction. You need to manoeuvre around the nasty spinners and flip them from behind. It looked like the shell was dragging on the ground and causing problems at Ideas Festival, perhaps going to smaller wheels and placing them as far forwards as possible would help?

From Philips other posts, I think he's looking for 4WD in the lightest package possible, I'm guessing he's considered using the ZigZag tracks as a simple pseudo 4WD. Stretch the tracks over two wheels and bang, it's done.
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https://www.halfdonethings.com/

Aaron is correct. It is difficult to get the wheels under the centre of gravity. Therefore, I am trying to work out ways of powering wheels in multiple locations without overly increasing size.

I would like to be able to drive off the top of a wedge. (I am looking at you, Cobra.) Tracks may let me drive off. Three or four chain or belt driven wheels per side would be interesting as well.
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So even the rain that falls isn't actually going to fill our dams and our river systems

ITs up to you, but my opinion is that unless you want to go to extreme lengths like George did with his tracked vehicle, then treads are not a workable idea. How about 4WD, with the second set of wheels driven by timing belts?

my track idea worked reasonably well with the grove in the red wheel tires the problem was the rubber belts stretched i was going to fix the problem by useing a small link chain that fitted in the groves and then rivet that to the rubber so the chain wouldnt be able to come out of the groves as it is puled tight between the two pullys - wheels drive is still by friction on the rubber belt

Marauder has bent the flipping arm at the same point after four fights. The HDPE has broken off the end of the ram (where the connecting rod impacts the flipping arm). I am considering putting Marauder on the shelf and building a cheap robot out of crap so that I can afford to repair it after events. It was still fun with a weaker robot. I have never been concerned about winning. I just like to have fun.
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So even the rain that falls isn't actually going to fill our dams and our river systems

That's sad, anything we can do to keep Marauder going? I think its important to have at least one good flipper in the country; if nothing else it keeps us from being 100% 'Brick VS spinner'.