Sloppy Belt

Not technically. Also of note on gantry style printers that use loops (also called endless belts) you do not want the belts too tight. Too loose is a problem if it is skipping on the gears, but too tight cause the gantry to bind and/or prematurely wear out the bearing surfaces.

 

That tells me your gantry is out of square. Those orange shipping clips actually are dual purpose, loosen all the set screws on the belt gearing and clip those in with the extruder at one corner, slightly tighten the set screws in that same corner. remove the clips and move the extruder to the opposite corner and clip those clips back in slightly tighten those set screws. repeat for the other two corners. That should square up the gantry and even out the tension on the belts.

I would link to a video or instructions but there appears to be very little information on this topic. Most of the gantry squaring appears to be for CNC machines (predecessor of 3D printers).

 

Bingo.

Mine came with one side knocked completely out of kilter. The rod that goes into the steel case was knocked out and that allowed the gantry to shift sideways. I had to press that back into position and it has been fine since. (this is probably over in my unboxnig thread if you want pictures)

 

With gantry style machines you need to think of it like this- the belts are all preset from the factory. Unless one snaps, tension issues are caused by out of alignment, they are closed belts- no adjustments to their tension. This isn't Robo specific, its all gantry