This is looking really great! I am especially excited to see how your custom linac turns out - my design was absolutely too complicated for its own good. You say bodging it with chains can lead to problems, but I found making a compact, custom gearbox for a linac to be an absolute nightmare. I think you are much better going this route.

I also love all the linkages involved in your weapon mechanism. Looks too cool when it's in motion like that. Good luck for Robodojo!