So the Creality Ender 5 is/was my first and only 3D printer. Over the years, as is tradition with Creality products, you replace parts and install upgrades here and there.
In the latest iteration only the frame is original. Everything else has been replaced.
Some of the highlights (screw AI for ruining that word)
-Cartesian -> CoreXY, inspired by the MercuryOne project.
-X strut replaced with two 10mm steel rods. The print head is in between the rods so that the reachable area can be increased.
-Redesigned toolhead allowing for a Phaetus Rapido UHF and Orbiter 1.5 or 2.0 extruder, as well as a BLTouch bed sensor.
-New bed, 314x314mm instead of 235x235mm.
-The bed motion system is placed outside the frame instead of inside. The bed will be raised to just below the top of the frame. The toolhead can freely move over the frame, the fan ducts will not hit the frame but the nozzle will.
-Oversized rails on the Y axis, 24mm rails of 530mm length. I got these from discarded lab equipment at my old job. They allow the toolhead to go over the frame bounds and allow the nozzle to reach the whole inside of the frame.
I now have a 260x310 usable print area, up from 220x220 with the stock unit. There is still room to improve and I believe 314x314 is also possible.
The FreeCAD design file is available here: https://www.printables.com/model/1867046-ender-5-radical-redesign
I think your belt paths is going to give you inaccuracies. I’m looking at the belts behind your x/y joints and the belts aren’t parallel there. I can’t remember exactly why that’s bad but I think it ends up with uneven movement across the entire motion range.
I’m not exactly 100% sure on this but I’ve seen people mention similar issues to people doing ender 3 switchwire conversions.
It might even out because it seems like you have the same thing on both both belts behind the gantry but I would look into that.
It causes uneven tension across the belt as the gantry moves back and forth. You need the non-parallel section of each belt to be at the back end
Ah I see the picture in the OP still has the old version. Indeed that is true and therefore I redesigned the YX joints to make nice 90 degree angles with the belts. In that version I made the idlers sit on the same screws that held the YX joint to the rail slider.
The belts did not make 90 degree paths from the stepper motor towers and also not from the YX joints to the toolhead. This caused uneven tension that was most noticable when the toolhead got close to the YX joint or when the YX joint got close to the stepper tower. The belt angle would change based on the location of either object and that changed the amount of force needed to pull it.
I’ve learned that the belts ideally make 90 degree angles when pulling something. One belt path comes out the left side of the idler and the other comes out of the right side. At the toolhead you insert the belt from either the left side or the right side to make the belt as straight as possible.