Can we see the STL? Is it all parts or just that one? What does a calibration cube look like on it?
It definitly looks like overextrusion that starts mid part. The first layers might be a small bit off, but not enough to produce that effect. the motion segment looks fine, it’s tracking like an Openbuilds X equipped machine should… 90 is a bit low for the bed, but it doesn’t look like you have any lifting at all. I’d be inclined to look at the extruder wire harness as a starting point, or the bearing on the idler arm. It looks almost like the motor is exerting a constant force, hits the midpoint and starts extruding more, then backs off again. A short could do that if it has a short, goes into full contact and then moves away, but that would be a very rare issue. usually seen with extended wire harness segments. Since position doesn’t matter though, that almost makes me want to think it’s something in the model itself. A thin outer shell that looks connected to the main structure with a void behind it would produce that effect.
It starts into the issue on the top layer when it starts making the longer straight segments, but the curved perimiter doesn’t seem affected. Issues on longer runs can be due to overcooling of the bore, or a failing heater carriage, but I would expect to see the same issue on the longer perimiter run unless its just running it enough slower that the fillament is able to completely melt.
If it were me, i’d probably verify the temperature on the hotend with a point and shoot thermometer first, if that comes back ok, maybe spring for a second refurb hotend and swap it out to eliminate electrical on the hotend, and maybe even go so far as to run a temporary extruder wire harness to route around the existing one.
is this in an enclosure at all? If so, how is the electrical board vented?
Are you running any of the new experemental firmware variants?