Printing like paradise


I threw together a design with incorporated, printable bushings. I have not tried this out yet, nor even printed it, but I’ll share it in case some brave soul wants to try it out.

I think these would need some light lubrication, maybe a bit of mineral oil.

UPDATE: This part is a WIP and has a couple known flaws:
1.) The clearance on the bushings is too small, so they will need to be enlarged with a drill.
2.) The slots for the captive nuts is the wrong internal shape, giving them too much wiggle room.
3.) The front lower corners of the carriage are a bit thin, and so the structure is not as rigid as it could be.


In that thread you (@SusisStrolch) linked they discuss about Repetier firmware vs Marlin. I guess Marlin was the 2nd winner there and showed strange movements with that speed test but the segments_per_second were 200 while in K8800 this is 60.

Is there some one here who wants to test Repetier firmware on K8800? I guess its a lot of work.

Can higher segments_per_second values improve the print quality or just cause more jerky movements?


Just tried to get in my ideas to the VS (carriage) from @Dr_Vegetable.

  • endstop plugged in from top of carriage, so no need to disassemble/assemble the whole printer when trying to play with endstop
  • tried to add “simply plug” feature for LM10UU, RJ4JP and RJUM1 bearings, Simply selectable via “bearing_type=x” in .scad source
  • added top/bottom brim and notches to plug-in the bearing into VS
  • small (trials) to optimize the model
  • three different endstop actuators (5,10,15mm)
  • Proposed resolution: 0.1mm layer height

.stl and .scad available from github

'cause I’m still at customer w/o access to my Vertex I couldn’t check the result.


Not really:


You mean not really a lot of work or not want to test?


I mean not really a lot of work


@SusisStrolch there is a lot to find in your repository! :+1: Are you still optimizing or is there a final version of the vertical sled for RJ4JP bushings with or without zip ties to find?


The repo holds my latest iteration of vertical slider.
Unfortunatelly I didn’t find the time during WE to print it.
I found some issues with the previous iteration

  • you MUST use zip-ties, otherwise the print head is too spongy
  • the nut hole catch was too tight
  • the bold hole through was too short, so the bold pressed against the bearing
    Here are the auto calibrate results after patching (drilling holes for zip, adding washers for the magnetic cups) my current sliders:
    Calibration OK rolling back.
    .Height:317.44 Ex:+0.00 Ey:-0.03 Ez:-0.05 Radius:107.80
    . Tx:-0.23 Ty:+0.13 Tz:+0.10

The latest iteration should work fine - simply test it :slight_smile:


I will! Probably today evening.
are the files I need to print, right?

Thank you for the design!


You only need the K8800-Vertical_Slider/K8800-VerticalSlider.stl.

I’ll will upload two additional test files - a single bearing holder and an reduced belt catch block incl. the endstop, so you can check the overextrusion and the sizes w/o having to wait 3hrs.


Did an update of the repo and removed unused files.
Print / assemble instructions:
layer height: 0,175 (= 1/2 nozzle dia)
initial layer: 0,245
wall thickness: 1,05 (= 3* nozzle dia)
top/bottom thickness: 0,7
build plate: brim
brim width: 6mm
brim only on outside
infill: 50%
pattern: gyroid
no support
no alternate skin rotation
no adaptive layers

You’ll need 3 bolts M3x12 (M3x15) for endstop adjustment.
No need to tap the threads
The endstop actuator should sit pretty tight in the belt catch block.


The zip-tie slot is too tight - I’ll rework it


Yes I noticed that but for me it look like the bushings hold already nicely without them. I think I picked actuators with a too small hole for M3 screws. I tried without screws. Now Delta height is too small in the firmware so I have to change it first.

I think larger values DELTA_HEIGHT are no problem but too small values are.


Believe me - they won’t! You’ll get horrible print results w/o ties (either zip or wire).

Connect your Delta to a serial terminal, 500.000bd and issue the command
G665 H330
Then you don’t have to recompile.

The diameter for the M3 is ok, it will cut it’s thread itself. Maybe it helps if you drill 1mm with a 3mm drill.


Just updated the repo:

  • increase slot width for zip-tie
  • increase depth of endstop flag
  • small adjustment to clearing distance for the endstop toe.

Now printing…


You are still using the Drylin bearings, and not steel, correct? This might be why the zip ties are so critical for you. I have been running my printer for many months without any zip ties on the carriages.


does not work at least for me. I think the soft-end stops prevent the nozzle to reach the bed if Configuration.h DELTA_HEIGHT is to low. Calibrate Center/X/Y/Z will crash into bed if DELTA_HEIGHT is to large.

@SusisStrolch You are right. Without ties torsion forces easily tilt the sleds out of plane.
I have not tried it yet with wire.

I also think that the actuator is to thick it scratches at the optocoupler of one of my endstops when homing. (sorry haven’t tried your latest upload yet sorry)

@Dr_Vegetable the issues I had with the steel LM10UU bearings they are quite heavy and my printer becomes even more nosy.


@shelxle sorry, was too sloppy explaining the calibration process…
M502 ; init from eprom
M665 H330 ; set initial height for calibration process
M500 ; store setting
G33 P1 ; Auto Calibrate

I will create thinner ES during the day. Did you measure them with a calipher? Mine show exactly 3.5mm width…


The steel bearings do have more mass than the Drylin ones, true. Did you try them, though? They have extremely low friction (compared to the brass bushings, anyway) which certainly makes up for a lot of mass added to the carriages. I found the performance to be excellent using them.

If the Drylin bearings have more friction, this will also behave like more effective mass on the carriages.

With steel bearings and no zip ties, the carriages can be twisted by hand to not be level with the bed, but in practice this does not happen because the bearings slide so easily.

For me, low noise is a secondary concern to printer performance.

I have not had a problem with the width of the endstop actuators on my original design. In any case, the tab should only need to be thick enough to interrupt the light, so 3mm is probably overkill. I don’t know how the width compares to the ones designed by SusisStrolch, however.


mine is exactly 3.5 as well. So I had a closer look and the collision is a combination of sled tilt and actuator tilt in the same direction. May be it is clearer on the photo:

@SusisStrolchplease try to set DELTA_HEIGHT 300 in your firmware and then send

M665 H330 
G33 P1 
G0 F5000 Z1 

on mine it stops and on the display it says Z14.84 .

@Dr_Vegetable yes I tested your sleds with LM100UU steel bearings. The have a lower tilt tendency and are easier to mount. I will try them with zip ties now. With out ties the sound was not just loud but, well hard to say, felt unhealthy to me.

To both of you thanks I really appreciate the work did. :+1: