I was so pleased with how my little CamRoller build came out a couple of weeks ago, that I decided I wanted to make him a little brother.

I designed the original to be capable of supporting my full frame camera with a decently chunky lens on it.

And I won’t lie, I was pleasantly surprised that it does so quite well! I didn’t even intend to put that big cinema lens on it, but decided to give it a shot. Even that big boy didn’t get the CG outside of the wheelbase….noice.

Unfortunately, that’s because that wheelbase is 200mm wide. Not as bad as an electric Hummer, but still pretty large on the work table. So I decided to make a ~50% scaled version, targeted at action cameras and/or cell phones.

And isn’t it adorable??

I think the 50% scaling really worked out nicely in terms of proportionality to an action camera form factor.

Interested in building one yourself? <<Grab the files here on Printables>>. If you do, please share your Make so I can see how it came out!

Before I dive into the BOM details, let’s take a little look at what’s holding up the GoPro.

The actual interface to the camera is provided by an off-the-shelf action camera mount. That camera mount has a 1/4-20 female thread, and it is actually part of the structure of the roller.

I designed it for a 1/4-20 x 3/4” flathead fastener. But I didn’t have any flatheads on hand, so I ended up going with a button head…nobody’s gonna see it under there anyway ̄\(ツ)/ ̄. It’s not ideal having the button head making just a line contact with the chamfer intended for the flathead, but I figure there’s enough meat there, it’ll be fiiiinnneeee.

That 1/4-20 fastener is clamping together the main bearing, and primary structure of the roller.

That structure comes from three components, Rot_top, Rot_center, and Rot_bot (I got it wrong in the image and was too lazy to export a new one…forgive me? :) ). These parts include v-grooves around their perimeters that serve as the bearing races to allow the roller to steer. Filling in those bearing races are a whole bunch-o-BBs.

The 1/4-20 fastener preloads this bearing together. When assembled, Rot_top and Rot_bot are rigidly fixed to each other, which allows for the gear on Rot_bot to provide the turning for Rot_top.