Runt - a wee flippy lad

So with Luchador taking a bit of a back seat and The Chilli Daddy only needing minor tweaks I’ve started on my new beetleweight project. Provisionally called Runt - its a wee flipper/lifter lad aiming for a target weight of 750g.

The design was a pretty simple process, I knew I wanted to pack full beetle weight performance in a half-sized package and to leverage some of the reliability lessons learnt on TCD. So a small billet build for the core chassis and a weight efficient TPU front end seemed like an obvious approach. After a handful of cad sessions I settled on this design:

The design lifts The Chilli Daddy’s drive wholesale stripping out the front wheels to save weight and condensing down the chassis as much as realistically possible to keep things light weight. Ditching all the spinner stuff and replacing with Luchador’s absurdly power dense 93kgcm servo.

Once happy with the design I got to CNC-ing the plastics. Here you can see a finished billet chassis sat in the footprint of a TCD chassis for size comparison - so smoll.

After that I did my usual approach of using 3D printed jigs and a hand drill for all the cross drilling operations and threaded insert… erm inserting.

This got me my core chassis plastics together. I dont have a good picture of it but the lifter uprights key around the internal billet geometry.

Another size comparison on the billet chassis vs The Chilli Daddy.

Next I printed the TPU front ends, these slide into slots in the billet keying around multiple features before being secured by vertical m4 bolts with sleeve nuts in the TPU side


Internally the compact nature of the build is a bit of a nightmare for squeezing everything in. Once I get some more servo connectors and can shorten and crimp on new connectors to some things it should be better but in the mean time well…

And here is where I’m at so far


Basically waiting on some hardox to finish up the front end and some small details to sort through out but mostly there.

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