potateCircles less circle-y
dual_sport_dork 🐧🗡️Do you have something stuck to one of the gear wheels or pulleys in your belt path?
No, checked that and the period of the undulations is speed dependent
Hmm. Well, then I have no choice but to concur with the others that this appears to be some manner of resonance issue. So much for being hipster about it.
Do you have the machine on a wobbly table? Are any of the armatures loose and able to move? The print head assembly is solid on its linear rails and doesn’t wobble if you grab it and move it around?