FDM 3D printing traditionally operates on a layer-by-layer basis, using a flat bed to construct parts. However, [Humphrey Wittingtonsworth IV] demonstrates in his video how this process can be significantly enhanced in terms of mechanical strength and print speed by experimenting with printing on a rotating rod instead of the standard flat bed.
[Humphrey] modified a Creality CR-10 3D printer by removing the bed and installing a regular 8mm linear rod under the hotend. The rod is rotated by a stepper motor with a 3:1 belt drive. This lets him use the rod as the printing surface, laying down layers axially along the length of an object. This means parts that can stand up to bending forces much better than their upright-printed counterparts.
Additionally, this rotational action allows for printing functional coil and wave springs – even multi-layer ones – something that’s not exactly feasible with your run-of-the-mill printer. It can also create super smooth and precise threads as the print head follows their path. As an added bonus – it could also speed up your printing process as you’re just spinning a slim rod instead of slinging around an entire bed. So cylindrical parts like tubes and discs could be printed almost as quickly as your hotend can melt filament.
Of course, this approach isn’t without its challenges. It works best for cylindrical components and there’s a limit to how small you can go with inner diameters based on your chosen rod size. Then there’s also the task of freeing your prints from their rod once they’re finished. [Humphrey] addressed this by creating mesh sleeves that snugly fit over his center rod. This limits how much melted plastic can adhere to it, making removal a breeze.
This is not the first time we’ve seen experiments that deviate from flat layers. It’s possible to print overhangs without support using non-planar slicing, and adding a fourth axis for the hotend.
Thanks for the tip [George Graves]!
