.It was the rise in effectiveness of the
Spinners that finally meant that we had to come up with a new tougher design. We decided to go with an evolutionary rather than revolutionary approach. The old design had many good features that we would want to retain.
The drive system had proved very tough and had also been used on a similar 30lb bot without problems so that was retained but would now have a option to fit bigger Speed 700 motors for more power and
speed. The slot, tab and nutstrip chassis design had proved its worth again and again. It made original construction quick and simple, repairs easy and had proved amazingly strong, holding the bot together
even after terrible damage.
The original design had been all been watercut from 3/16" and 1/4" polycarbonate (Lexan) and this had resisted impacts well for a couple of years. The rising power of the spinners had begun
to cause major cracks and splits to develop even in new parts. To prevent this problem a lot of the new parts will be made of UHMW. This plastic is not nearly so strong or stiff as polycarbonate but has enormous
resistance to cracking.
Another problem with the original design was its short wheelbase which made straight line driving tough and restricted interior space. An increase of almost an inch should improve
both.
The last version of CheepShot 3.0 had sloping sides as well as front. I would have liked to retain this feature but it greatly complicates how the front corners joined together. This was Ok for a one
off but for a design I wanted to make available as a kit it would add a lot to the cost. The front corners are also where most damage occurs and replacing custom machined parts on a regular basis could get
expensive and impossible at short notice.