Ender 5 Plus Exoslide X Axis Brackets

Why?

The Exoslide kit for the Ender 5 Plus is a nice upgrade from the stock v-slot wheels if you can't afford linear rails.

However - the mounting brackets and design, while being better than stock, still leave something to be desired when used with a heavier direct drive extruder (in my case, a Hemera).

The X-Axis 2020 extrusion has a tendency to twist forwards towards the bed, inducing resonance on Y-axis movements, and effectively limiting print acceleration due to artifacts.

How to fix this?

Without replacing the extrusion itself with e.g. a 2040 or other stiffer solution, the only thing we can do is stiffen up the way the extrusion is mounted at each end to the Exoslides. I designed a bracket which allows the extrusion to be bolted on from 3 directions - one side, the end of the extrusion, and from the bottom or top. A small slot is added to allow the belt to run. 

The extrusion is attached using 2 x M5 T-Slot nuts, 3 x M5x8 BHCS and 1 x M5x12+ BHCS (or an M5x8 with additional T-Slot nut), and the brackets are attached to the Exoslides using the standard M4 BHCS bolts that come with the Exoslides themselves.

Print Settings

This is a functional part, so make it strong - print in PETG, ABS or ASA. Design is for PETG so with different shrinkage you might need to modify the holes.

• 0.2mm layers (better overhangs on the horizontal bolt holes)
• 3+mm perimeters
• 40+% infill (Gyroid, modify higher for less dense infills)
• No supports (The vertical bolt hole with recess has a sacrificial layer that can be removed with a pair of clippers).

Improvements

In my own installation, with the brackets printed using PETG with the settings above, I increased my maximum Y acceleration from ~3000mm/s^2 to over 6000mm/s^2. The X axis is capable of over 7000mm/s^2. It is still possible to twist the X-Axis extrusion but I think the only way to fix that is to upgrade to a stiffer extrusion (2040 or similar - but this would mean buying new Exoslides).

Building

1. Take your existing X-Axis gantry apart.
2. Remove all the mounting hardware, belt clips on the Exoslides on the Y axis.
3. Check your Exoslides without belts and make sure they all roll smoothly, replace your wheels or bearings if none of them roll smoothly.
4. Tap each end of the 2020 X-Axis extrusion in the centre hole, using an M5x0.8 tap.
5. Put the longest M5 you have into the “central” hole of each bracket, with the bolt facing UPWARDS. It's not possible to put this in once the bracket is installed due to clearance issues. Tighten it all the way.
6. Attach the brackets to each Exoslide using the M4 bolts, placing the existing belt brackets ON TOP of the new bracket. If you have BHCS bolts that will sit flush inside the recesses under the extrusion, then install those for more security.
7. Place the extrusion on top of the bolts inserted from the bottom. Line the bolts up with the existing pre-drilled-and-tapped holes (or use additional T-Slot nuts if this is problematic). Turn the bolts from the bottom to pull the extrusion into the brackets. You'll need allen keys with a ball head as clearance is an issue.
8. Make sure to feed the belt through the channel at the end of each bracket - you'll have to feed it through while installing the extrusion as the metal clips at the end of the belts are too big to fit through the belt gap after installation.
9. Add and tighten the end bolt, and install side bolts using T-Slot nuts in the extrusion. Make sure all bolts are “hand tight” (bear in mind an M5 bolt can crush PETG pretty effectively so don't go too ham on it!
10. Reinstall the motor and the belt pulley at the other end, horizontally, with the motor and pulley aimed down and towards the back of the printer (where the Y axis motor is).
11. Move the belt clip from the top of the extruder gantry to the back.
12. Check and move your X and Y axis endstops to so nothing crashes. This is an exercise left to the reader, but I managed to mount both using no extra pieces (only things from the existing E5+ bits, for example V-Slot wheel standoffs).
13. Re-test resonances in Klipper and hope things were improved significantly.

YMMV. If you break stuff, it's on you. If you don't see any improvement, then sorry you wasted the filament. Hopefully these improve your E5+Exoslide experience significantly.