Info

Added: Oct 05, 2017 06:14
Author: Garrett Sloan
License: Creative Commons - Attribution

Description

Want to add Cable Chains to your MK2S but don't want to modify or reprint the Rambo Case or Extruder assembly yet? Then this might just be for you...

Looking to add cable management to replace zip ties? This might also be for you...

(Regarding MK2 Support Read below)

Originally inspired by:
http://www.thingiverse.com/thing:1725591
http://www.thingiverse.com/thing:2224025
http://www.thingiverse.com/thing:2240114

I wanted to add Cable chains to my printer as the spiral wrap/filament was beginning to sag and the x/y wraps snagged on other parts causing the Axis's to skip a couple of times.
Planning/designing other mods at this point I'm not quite ready to reprint the extruder, or Rambo case, so I came up with another option... adapters.

I initially built this as a minimally intrusive mod and factored in a couple "fixes" to deal with issues in other chain kits I've read about, assembly should be straight forward, a few parts from the spare bag and a couple pieces of 1.75mm filament is all you need!
(besides the parts... they're kinda important...)

As time went on (and after tazguy79 got me inspired to finish up the Z-Axis) I've expanded it to chain all the axis which I think completes this thing, and built on the same theme with cable management ducts (moved to a new Thing: https://www.thingiverse.com/thing:2472994).

There is lots of debate on how many chain segments are needed; In the end it doesn't matter and will vary from printer to printer.
As long as the axis's move freely you have enough. I personally went with a few more than others to match the original wire length.

There are 2 versions of the chain link included, one with "ears" and one without. I found printing 16 a time eventually one clip would pop off and ruin the batch, the ears add enough bed adhesion to keep any from popping off, and it makes taking the pieces off the bed easier.

Comments greatly appreciated, let me know what you think!

Print Settings

Printer Brand:
Prusa

Printer:
Prusa Mk2

Rafts:
No

Supports:
No

Resolution:
.15 Optimal

Infill:
5% (or more)

Notes:
All Parts printed in ColorFabb PLA/PHA, 215 1st layer, 200 remaining, 60C hotbed. You may want support on the Y-Axis part, I didn't on the part I used in assembly but it might help.
Infill varies between parts, most were printed with 5%, the clips were 100%.

Post-Printing

Build & Assembly Notes:
General:

You may need to drill the holes up a size, or sand a couple of the small features to have them fit, I designed/printed everything quite tight to account for shrinkage and allow for fine tuning of the fit.
All parts are designed so the wires can be slid into them, there should be no need to disconnect any wiring.
X-Axis:
The Extruder mount is inspired by Prusa's MK2S screw attachment, press the two plates on each side of the screw, then press the mount down on top. A single zip tie tensions it and holds it in place.
Note, you may need to file the bottom corner that will be closest to the Rambo case slightly, one make of this so far had clearance issues at that point.
The factory filament support stays, it and the cables route almost the same way as stock, up into the chain connector and secure them with a 2nd cable tie. Its OK if it rotates a little, its designed to do that as needed at the axis limits.
The Rambo mount is easiest to install if you pass the wires into it first, then slid it into place on the Rambo case, put the clip in place to close up the mount, and pass a zip tie through everything (I started feeding it into the side closest to the door) out the back and zip it up which holds everything in place. Then pass the stock filament through the mount and into the original hole, the filament adds rigidity to the chain and keeps it from sagging.
Y-Axis:
Hotbed mount... again the filament stays! its going to help keep the chain bent and keep it from rubbing on the y-axis rail. Installs just like the stock part, once the chains are clipped on they hold the two sides together.
For the Rambo Case mount I snipped ~30mm off the factory filament here... (almost no mod?) the filament goes into the mount with the wires then butts up against the top of the vertical section. (under revision to add a hole for it to slide into). Use the ~30mm cut piece once the mount is pressed in place to pass through the larger hole into the factory location to lock the mount on. A short piece of 1.75mm filament goes through the 2 holes in the tabs that press in to lock it in place (in one pic you can see the white filament I used).
Z-Axis:
The Z carriage mount prints as the rest without support, the Z Rambo mount I printed with supports on due to how its oriented and to support the clips. There is a intended small square at the tip of one clip, this is to get Slic3r to print a small pad so the tip of the clip doesn't try to start in free space.
Installation should be straight forward, in my case currently used 14 chain links, and 1x M3x18 screw (from spare bag) to mount the carriage support to the x-axis motors free hole.
The rambo mount is a little tight and needlenose pliers may be needed to press the filament through the supports.
A short piece of 1.75mm filament goes up through 2 tabs, over through the 2 horizontal ones then back down through the other 2. I used a piece of flexible filament, if you use PLA it might be easer to do with 2 pieces only in the vertical posts only.
Note! to get the rotation clearance needed at Z 200+ the chain link that connects to the x-axis motor support needs a slight modification to fully rotate 90deg, refer to the pictures for info, the modified is on the left (I appologize the the quality, these were some old links) basically the two corner "pockets" on the top side need to be cut back a little, I may update the mount in the future but is is a much quicker solution for this single chain.
Finishing Axis (Axi? Axis's?):
Finally, snap in the chains, route all the wires into them and then put in all the clips.

Files

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