How to cover, support and protect cables to the X carriage on a CoreXY printer

I'm getting close to finishing my CoreXY printer - the only major component to be fitted is the printbed - and while I'm waiting for some stuff to arrive I'm contemplating how to do other things nicely. The current conundrum is how to cover and protect the wires going to the X-carriage. My requirements are:

1. Must be able to fit over existing wires
2. Must be reasonably easy to add or remove wires at a later date
3. Must be capable of holding the wires up so that they do not tangle with the carriage or frame
4. it must be a tidy engineering solution

The original design (C&G Printer) uses the sort of cable wrap used to keep TV wires tidy. This certainly covers points 1 & 2, and doesn't look too bad for point 4, but it's too floppy for point 3 - it droops down below the carriage. In the original design I believe that the bowden tube went through the same wrap as the wiring, and that kept it up, but I want to keep my bowden separate (following previous experience, I often had to remove the bowden tube to fix problems). At the moment I have a spare bit of bowden tube alongside the wires inside the wrap to provide some springiness, but this isn't an ideal way to do it.

I have experimented with a horizontal cable chain, but even though it's quite rigid in the 'non-bending' direction, it still droops enough to potentially cause problems. This might still be the solution as in theory it covers all 4 requirements, but I've been playing with it for a few frustrating days and it still doesn't quite make the mark.

So now I'm wondering if anyone else has come up with a solution, or has seen something worthwhile?

Afterthought: please note that I'm not criticising filipe's original design - it works for him! It's just me being fussy and finding more jobs to do...

Edited 2 time(s). Last edit at 11/10/2015 11:45AM by David J.

Try looking at the PET+ braided covering people use for cleaning up cables on their PCs. You slip that on with a piece of heat shrink at both ends. Looks nice and cleans things up.

How about a ribbon cable, folded back on itself? This is what my Ormerod 1 uses for the bed, and it's never caused me a problem. I think some dot matrix printers used this solution too. If you want something more durable, google "extra flexible flat cable".

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

The trouble with braiding is that it's difficult to add or remove wires after the event - point 2 above.

I've already got all the wires in place, so I'm not too keen to replace them with flat cable!

The main problem of my solution is to flexible, it was necessary to add the ptfe tube to add rigidity and secure both ends. Used this solution because i already have the tube at home.

My initial solution was to use an simple pvc flexible tube, something like this:
[www.ebay.com]

Other solution is use an plastic injected cable chain, is better the printed ones and the best solution if you want the printer in an enclosure:
[www.ebay.com]

Quote
filipeCampos
My initial solution was to use an simple pvc flexible tube, something like this:
[www.ebay.com]

I think that I have some of that tubing in my garage, but split along the side (which would be convenient, as long as it stays rigid). I might give it a try.

Quote
filipeCampos
Other solution is use an plastic injected cable chain, is better the printed ones and the best solution if you want the printer in an enclosure:
[www.ebay.com]

Actually, the length of chain I've already made is very rigid across the bend, so I'm not sure that would be any better (they don't ship to the UK anyway).

Both solutions still have the problem that I would have to unplug everything and thread it through the tube (if not split) or chain. My chain is open-sided, but closing it is a pain, requiring lengths of filament as closures. Thingiverse link. This is why I'm looking to see what others have done.

Quote
David J
The trouble with braiding is that it's difficult to add or remove wires after the event - point 2 above.

I've already got all the wires in place, so I'm not too keen to replace them with flat cable!

It's not too bad as long as you didn't skimp on the diameter of the braiding. Also, I highly recommend a hot knife-- you can cut/seal the ends in one step.

Alternatively, you could use what they call "split loom"-- a spiral tube with a slit down one side.

Having tried both, I prefer the braid, even with the hassle of adding wire.

I like using braid and spilt tubing but with - Tesa 51608 19mm x 25m Adhesive Cloth fabric Tape Cable Looms Wiring .
The Tesa tape can be purchase from Ebay.
Tesa tape is not a PVC product like insulation tape.

Its a little hard to remove, usually you have to cut it off wires and it doesn't go sticky or fall off.
It also good for car wiring looms etc.

Other option is using Velcro to keep wiring filament feed tubes all together.

Cheers.

Hi guys,

I recently used ribon cable on my printer.
You need to use several wires for heating elements, and the ribbon cable falls easily.
I still think braid sleeving is still the best option because you can put anything in it, even bowden tubings.
It's silent and clean, there's a lot of colours avalable.
If you take a sleeving large enough, managing cables instide is no big deal.
Choose 12mm or larger, depending of how many things your printhead carries.

++JM

I think I've sorted it - I've used the cable chain I mentioned above, but with alternate links - type A and B in the Thingiverse design. I added more clearance between the chain and the frame, and it seems to be OK. I'll post some pictures once I've got the Z-axis sorted (currently being printed).

And here are the results:



The black pieces are the "A" pieces from the Thingiverse design I mentioned in an earlier post, and the red ones are the "B" ones (I was running out of black PLA when I printed the "B" pieces!). "A" goes outside the curve, "B" goes on the inside to contain the wires. I had to design a number of mounts to fit on the extrusion, but all the chain pieces are as designed.

It certainly works, although I do have to be careful - it is very strong in normal motion, but things break if you lean heavily on the chain (guess how I found out).

Currently I plan to use a bowden extruder, but if I change to a direct one then I'll have to rethink the X carriage chain mount.

I really like the chain design of the Z axis, very good solution.
I think i will use the same chain for the Z axis and add your design to the g&c printer. I will put the z chain in the back instead of the right side.
When the bed in all down, is necessary to secure the chain? not sure if the chain will be secure in this situation

About the x,y chain, I have some questions:
- it is possible it will break because of the fast moving of the carriage?
- do the chain make noises when the carriage is moving?

both chains are used to support only electric cables, i think smaller chains will be better.

Edited 1 time(s). Last edit at 11/16/2015 12:38PM by filipeCampos.

The chains are quite strong across the section and when they are straight they are rigid in all directions apart from the one direction they are supposed to bend. So although the Z chain looks unsupported, as long as both ends are firmly fixed vertically then the upright bits are straight and firm, whatever the bed position.

The XY chain bends very easily and shows no sign of breaking - in fact, it's really difficult to get the sections apart after assembly. There's no noise from the chain.

It's best to use a fairly wide section on the belt, especially on the XY, otherwise it tends to droop. Also, the space for the wires is a lot less than the total width.

Perhaps you could try printing 3 of each type, A & B, and try them out. They feel really stiff and rough when you first connect them together, but soon move smoothly once you've worked them for a while. After assembling my chains I held an end in each hand and flexed them by moving each hand up and down (you have to do it to understand that action!) - once you've done that 20 or 30 times they all ran well.

Let me know if you want my chain mounts - they were designed in OpenSCAD, but I can supply the source file and STL for each part. The source files give the dimensions that you could use in your own design package.

send me the chain mounts for the z axis.
Can you send me in step format? If not; send me the openscad format.

You have used this chains?
[www.thingiverse.com]

That's the one but you have to read the instructions, as you will need 2 files from the original design it was based on (Thingiverse). You will have to have OpenSCAD loaded on your machine so that you can generate the STL files. I don't know if you have ever used this tool, but the code is just like any simple programming language, e.g. HTML. I'm sure you will understand the code structure as soon as you look at it.

I will sort out the files - sorry, it will have to be in SCAD. I'll also do some photographs to show you how and where I fitted them. Actually you will only need 1 chain mount at the frame end, as the other end fixes directly to the bed support.

Edited 1 time(s). Last edit at 11/16/2015 01:18PM by David J.

Filipe,
I had an afterthought - have a look through Thingiverse and YouMagine and see if there is a cable chain designed in a format you like. I can send you details of the way I fastened mine, and you can adapt it to suit your own needs.

Be careful with drag chains to ensure that the bending radius stays large. If you use a small bend radius with ordinary wires inside the drag chain, the wires will fail. I experienced that type of failure a year or so ago. I eventually changed from wire cable to flexible polyimide ribbon cable.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Thanks - I'll keep an eye on that.

I have an problem: i do not have space to put the chain one the back of the printer. The only possible way is to put the 2020 bar that is one the middle of the back upper. Now i understand why you have yours Z chain on the right side...

Edited 1 time(s). Last edit at 11/17/2015 06:10AM by filipeCampos.

Yes - it was the only place I could find to fit it!

It was also very easy.

Edited 1 time(s). Last edit at 11/17/2015 06:45AM by David J.