MPU-9250/6500 mount for Ender-5 S1

THIS HAS BEEN SUPERSEDED BY MY IMPROVED GROUND-UP REDESIGN

A secure mount for your MPU sensor on the Ender-5 S1 print head.

Secure fit: Priority was given to ensuring that the mount is secure; the official Creality mount for their Sonic Pad sensor has 1.5 axes of contact at best, with no contact on the Y axis and a large overhang on the Z axis, whereas this mount has 3 axes of significant contact and should stay perfectly still during calibration.

Location: Placement of this mount is centred on the print head and only exceeds the print head's bounding box by 1-2mm on the front side (above the printer frame). Creality's mount extends out on the stepper side of the print head and for a larger sensor like the MPU would come very close to colliding with the stepper at its endstop. Additionally, the screw holes I've chosen are both long threads, whereas one of the holes Creality's mount uses is very short making it harder to find a suitable screw at your local hardware store.

Permanence: This is designed to be permanently mounted and connected, so recalibration can be as simple as activating it in the Klipper menu. Therefore it had to be minimal and aesthetically pleasing (as much as possible while still being “a box”) and this informed the design of the mount parts that follow the contours of the printer's head.

Print and assembly

My print files are available in the Thingiverse listing, but Printables doesn't allow them as they have Klipper macros which it considers non-standard.

I recommend printing in PET for maximum rigidity, though PLA is also be fine. The fit is intentionally very tight, so I suggest calibrating Pressure Advance for your filament first. If using my provided print files, they've been calibrated for generic brand PETG which may work for yours, or you may need to replace the SET_PRESSURE_ADVANCE values with your own.

If you're using PrusaSlicer, enable Detect bridging perimeters in your print settings to prevent it printing in the middle of nowhere when switching from hex nut to thread; other slicers should have a similar setting. If you've previously enabled Thick bridges, turn it off for a nicer emboss on the lid.

No supports are required.

Non-printable parts:

• 4x M3 screws; 4mm is best but longer is OK (I've tested up to 6mm) provided you don't mind them coming out the bottom of the box a little
• 2x M3 hex nuts

Configuration

It's probably not necessary as Klipper doesn't really care about the vibration direction, but as the sensor has been rotated 90° I added an axes_map to my printer.cfg configuration to counteract this:

[mpu9250]
i2c_mcu: rpi
i2c_bus: i2c.1
axes_map: y, -x, z # 90° rotation