Highly recommend making this bot.
I made some changes, not to the design but just to the parts / assembly.
I used these foam tires - 40mm OR006-00603. These are +-2g lighter than the 40mm Pololu wheels, with marginally better traction. They are also waaaay cheaper and take massive hits without shattering. You just get chunks of missing foam.
The wheels - https://hobbyking.com/.../light-foam-wheel-diam-40-width...
you have to drill the axel out to push mount them.
I used this ESC with the BE1806 with great results. Very light and compact. https://www.banggood.com/DYS-BL20A-Mini-20A-BLHeli-ESC...
Also take a look at using a stainless steel ruler for the blade.
I run this on my Shrapnel clone and its way better than Aluminium bar. I have bent 3mm mild steel weapons on other bots and taken chunks out of the poly carb without any issues!
Also to help with mounting the blade, I used the supplied prop mount. I used one of these, melt mounted into the bottom plate as a bushing for the motor mount shaft. Grind the thread back. https://mecha4makers.co.nz/.../sintered-oil-less-brass.../
I printed with 2.6mm walls and 1mm top/bottom to ensure that the print is 100% without infill.