Mk 12. (partial reconstruction of ~). First of the "X-wings". Uses one rubber band across top of arms and bits of foam to allow flush contact.

Mk 13. Much shorter cross-arms.

Mk 14. ran for 36 hrs (before motor failure)

Mk 15. BIG motors, geared down 1:3 twice (ie 1:9) - still runs hillariously fast. Simpler contact arms though... first of the "Y-wings"

Mk 15 gears

Mk 16. Micros geared down 1:3.

Mk 16. gears

Mk17. belt drive 2:1, narrow wheels

other side of 17.

15,16,14,17.

15,17,14.

mk20

some Mk18s clustering in the pen (kind of :)

doing something else (all right, they're not doing anything really)