The shorter side on the X makes less air movement across the bed thus retaining more heat in a localized area. Think of all printer motions like little fans themselves. Moving a palm frond or paper fan moved in a large motion moves more air.

The moving bed and undesired cooling it causes is one of the largest weak spots in Cartesian printers.

So on a bed slinger you can orient a print any way you want.

But, a bed slinger has a lot more mass to move when moving the Y axis (the bed, your print attached to the bed) then it does on the X (the gantry and tool head)

So orienting your print where longer moves are on the X axis has a couple benefits

• accelerations on X are less likely to introduce ringing The
• Heavier prints are less likely to come loose from the shifting (although if this is the case you probably should slow down or work on adhesion issues overall)

You’ll see something similar with Voron prints where some orient the infill to be at 45 degrees since that overall works best with how CoreXY AB motors work. E.g. only one motor is pulling vs both working in tandem at other angles.

https://github.com/AndrewEllis93/Ellis-SuperSlicer-Profiles?tab=readme-ov-file#45-degree-profile-vs-standard-profile