an rc car has been on my 3d printing to-do list for a long time. sourcing the right parts for the existing models proved to be difficult. hence i designed my own car.
this is the chassis for a 1/6 scale model of a volvo c30 that i intend to build. it has a total length of around 700 mm and a width of 300 mm. most of the off-the-shelf components are either from traxxas or hobbyking.
the design mainly consists of the front and rear assemblies that are attached to a base plate that holds all the electronics components. the 3d printed components have already gone through several design iterations because of crashes. but it has not been tested to all possible extremes. this is also the reason why this is a work in progress. i'll update the design after each improvement.
a few further comments: - i only uploaded the creo elements express file so far since i'm constantly modifying the design. i will upload stl files once the design is robust enough. - it's only a half model because creo elements express has a 60 components limit. - i designed the spur gears with the planetary gear designer that can be found on my website. - i print all components in abs with 3 shells and 20% infill. - creo elements express is free to use and can be downloaded from the ptc website.
here are three videos: http://youtu.be/Pm3R1xp-ONg http://youtu.be/v0asU2l1kwU http://youtu.be/AF1kFuWpaDc
further information on the project can be found here: http://www.muellerr.ch/rc-car-chassis-16/
update 2014-07-18, version 166: the motor pinion of version 163 is a stock part made of steel from hobbyking. the gear teeth are less than 4 mm wide so they tend to eat the 3d printed spur gear's teeth. version 166 has a modified gearing system having a higher reduction ratio of 6.4:1 from the motor to the axles. additionally, the gears are around 10 mm wide. this should improve durability substantially. there are now two versions of the spur gear in the model. one with zero play nominally and another with 0.2 mm profile correction that adds a bit of play.
update 2014-07-20, version 168: gear reduction ratio increased to almost 8:1. this gives the model a better low speed characteristic.
update 2014-09-12, version 176: improved directional stability thorough the addition of a 12° caster angle. higher turning speeds thanks to 3° camber.
update 2014-09-21: each one of the gears has failed at least once recently while driving on a 3s lipo. the problem appears to be the low strength of abs. hence i'm finally switching to nylon (taulman bridge). this material is so tought, it's even a pain to remove support structures.