Inserting an extension to the OEM extensions cables

I have been rearranging my shed & now would like to install my controller on the right side of my table, partly because it gives me a direct line of sight to my wifi mesh system, resulting in better reception.

I’m assuming the two “Y” cables should be able to just swap over (yes they do fit & yes i realize to swap the plaug at the controller), however the issue I have is the “X” & “Z” cables. I did originally get the extension pack, but even that wont be long enough.
So my question is twofold,

  1. What sort of cable would be required to make an extension, ie; cat 6???
  2. Could i simply cut the existing extension cable midway, then install a suitable male/female connector to each existing end of extension cable then get suitable cable with the corresponding connectors to “extend” the extension cable.

I know should have ordered extra extension cables at the time & now, because I’m in Australia could end up waiting a while for snail mail, so thought this may be a suitable solution.
Will it work or am i talking out my arse.

Appreciate any help from the brains trust

Suggestion to Onefinity regarding the extension cables, please give people some more options other than 2’ & 4’, cable is cheap, have a 10’ ft option for those that may configure there setup differently.

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Hey Moggy,

since they have to be flexible, you need stranded wire. If you want to use the same connectors as on the stock cables, the crimp contacts are for 24 AWG – 18 AWG, so I would take 18 AWG. If you want to make a cable identical to the stock cable, which has neither PE wire nor shield, you simply need a 4-wire cable.

Be sure to have the correct crimp pliers ready as specified here.

Of course in engineering, wires are not measured in wire diameter but in cross-sectional area, because the cross section is directly proportional to its strength and weight, and inversely proportional to its resistance. The cross-sectional area is also related to the maximum current that a wire can carry safely. Wire diameter is not. Wire sizes are standardized internationally in IEC 60228.

AWG is issued by ASTM and is mainly used in the US. Molex and Amphenol specify wire strength in AWG units instead of IEC 60228 :frowning:, so what can you do.

Here is a nice comparison chart for American Wire Gauge to IEC 60228 in this file:

You surely can, but the connectors (not the controller) are the weak spot on this machine (especially combined with the lack of strain relief on this machine). Many people will prefer longer cables to avoid connectors in the middle, because the more connectors of this kind you have, the more possible causes for bad connections.


Thanks for info, which has got me thinking, so if i may, a couple more questions.

  1. Do you know or have any details of the plugs (the bigger ones) that connect onto the “X” & “Z” sockets? Reason being, is that as you said the connections are the weak point so, I’m now thinking that rather than adding more connections, i should try to reduce them, so now thinking, that if i can source the same plugs as the OEM & suitable cable, then i would just make a new one to suit my situation (if that makes sense), rather than using extensions.
  2. In amongst the links you provided, i thought i read that when you got your machine that you would replace the OEM connections with superior connectors, have you done this & if so would you share (the link if you have already posted) the actual items & process & this maybe a better long term fix.

My biggest issue is accessibility to type of equipment, or more specifically the time to get it.


There are some resources in the following discussion…

Wire connector discussion

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Hey Moggy,

sorry I don’t have much time at the moment but hope this quick answer helps:

the references to the connectors used with the Onefinity and the information to make your own stepper cables can be found here, and the Application Info here.

Retrofitting better connectors

and adding shielding and PE wire to the stepper cables

Yes that’s right, I said that here, I was planning to do that. But I haven’t done it yet, and I’m not sure I will. For one thing, I haven’t put the machine into operation yet because I’m still waiting to move to have a bigger workshop where I can start up the CNC and some other machines.

Secondly, although I ordered a Onefinity Controller with the Onefinity CNC machine because I’m fascinated by the Buildbotics project (and the Onefinity controller is a fork of it), I had planned to use a different controller in the first place, so I’m not sure it’s worth the effort to upgrade the Onefinity controller to other connectors. The question is especially whether you just replace the connectors on the rails of the machine, which would become more reliable, especially when you have to sometimes unplug them, or whether you also replace the sockets on the controller housing. That would be a certain amount of work, because the stock Molex/Amphenol jacks are soldered into the pcb, and you can’t replace them directly with anything else, because neither the anchor points in the pcb nor the holes in the controller housing will fit other jacks in place. However, serious sockets that are led to the outside and are operated by the user should not be anchored to the pcb anyway, but are fastened with a nut in the housing (like the Phoenix Circular Connectors, M12 in this case)(see links below). It would be easy to solder the short wires of the new Phoenix M12 connectors into the solder points on the pcb after having removed the stock jacks, but it would mean you would have to punch corresponding holes into the controller housing, or use another housing with appropriate holes.

Also, after finding suitable Phoenix industry-grade connectors with gold-plated connectors in their M5–M12 Circular Connectors Catalogue (PDF), I added up the costs, and I come to more than 200 EUR, depending on whether I want to add an additional possibility to separate the cables also between X and Y, to be able to remove the X-axis as a whole (e.g. for transport). That’s an idea, but this will not work with the 3d-printed drag chains parts I’ve seen so far. I would have to design those, but as mentioned above, I haven’t even gotten to the place where I can set up the machine and get it running.

But anyway, I can tell you what plugs and sockets I have picked out for stepper motors though. However, I would not take 4-wire unshielded cable like found on the Onefinity stock cables, but always 4+PE+Shield (I buy cables from LAPP).

For the stepper motors, I picked the following connectors:

Flush-type connector - SACC-E-M12FSK4PE-M16XL/0,2-1,5 Nr. 1425636
Power connector - SACC-M12MSK-4PECT-CL SH Nr. 1027474
Flush-type connector - SACC-E-M12MSK4PE-M16XL/0,2-1,5 Nr. 1425635
Power connector - SACC-M12FSK-4PECT-CL SH Nr. 1027476

Anyway currently, if you own a Buildbotics or a Onefinity Controller, I would tend to leave the stock jacks in the controller housing, but retrofit strain reliefs everywhere on the machine. This should first drastically reduce the susceptibility to errors, and secondly, I would make the cables for the Onefinity in any case with the length to measure and with the best craftsmanship (correct crimping insert) and avoid any superfluous connection.

If I were sure I was going to stay with the Onefinity controller and stock steppers, I would consider retrofitting gold-plated circular connectors at any point I might disassemble the machine in the future, whether for transport or for service and diagnostics.

Also if you think of replacing the stock steppers by closed-loop steppers or by servos one day, often these come with their own connectors.


Well, its apparent that onefinity will offer no support, or advice for that matter, to help resolve my problem.
When i asked for info, it was a “no suggestions for mods as they are not supported”, which i understand & thats fair enough, but when I posed the question as to whether adding another extension was a workable solution the response was “You can try a more than one extension, but if it doesn’t perform correctly, the first step would be to remove extensions” .
Would say I’m quite dissappointed with that response & it would seem that little to no actual testing to determine the max length of cabling has been done to provide a clearly defined answer.

Solution - keep the controller on the left side :confused:

I mean for goodness sake all I’m trying to do is move the controller to the right side of my table, not to another room


I got a very similar response when I expressed the standard cables should be slightly longer than they are to accommodate various setups (some of which they advertise and have video instructions on setup).

I’m not sure what has changed, but the forum response from Onefinity has definitely changed, lately.

I bought longer cables on Etsy. I don’t like the extensions because they add an additional point of failure.

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Because of the symmetrical nature of the machine, you should be able to flip sides at will. I originally built mine with the controller on the left, then recently decided to try it on the right side (the more traditional controller side of commercial machines). Seemed odd to me, and I decided I didn’t like it, so I once again switched back to the left side. Assuming you aren’t wanting to locate your controller farther away, your current cable configuration should be usable as-is. If you do add extensions, I wouldn’t go too crazy with excess length. Remember, these small wires are carrying a good amount of current to drive the motors, unlike the requirement of data cables. I actually had to replace a couple of my small Molex connectors because they melted due to the current. I’m running an aftermarket controller, but it still runs on the same power supply.


I’m sorry, we cannot offer suggestions on how to modify wires as it’s aftermarket and done incorrectly would void your warranty and potentially damage the machine.

As for the extension length, in our tests, up to 4 extensions work, however, the reason we do not give an exact amount is because this was in a controlled environment. Every home environment is different and has different things that will affect the signal. This is why we suggest using the shortest run of wire as possible and do not give a specific number as it’s not a ‘one size fits all’ situation.
Hope you understand.


You cant “flip” the X carriage & to spin it around would then position the router at the back. Unless I consider stripping it back & reversing it, but then would the code run in opposite directions to what is intended, ie; move left instead of moving right???

Well to me that says the OEM wiring/cables are undersize. I hadnt heard of that before.

Hey Moggy,

I don’t have much time today either, but hope this quick answer helps:

no, you can adjust this with a setting in the Controller. After having flipped the axis, you can go to the Motors Tab and select Motion: “Reverse”.

It is advisable after ordering the Onefinity CNC machine to RTFM:

  1. Read the Fine manuals
  2. Watch the videos from the “Support” Playlist
  3. Read the FAQ documents

There you find:
Support: How to Flip The Y Rails Backwards (cable in back of machine)

After having flipped the axis, you can go to the Motors Tab and select Motion: “Reverse”.

You can mount the Z assembly to either side of the X gantry. This is mentioned in this video:
How To Flip The ‘Stiffy’ (3rd Rail) Around

Some people want to put the controller and have their wires on the right side of the machine. This video shows how to flip the rail so that the z slider will fit on the other side.

Note that without 3rd ‘stiffy’ rail, you can simply mount the Z assembly on the other side of the X gantry.

Hope it’s now clear what Bill @Machinist meant with “the symmetrical nature of the machine” :slight_smile:

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Yes, it indeed would postiton the router at the back. But again, it’s a symmetrical mounting block so when you flip X, you’ll need to remount the router on the front. And also remove the 2 bolts that hold the X axis nut in place, and spin the nut 180 degrees (else the oil hole access screw will be in the way). And yes again, there is a setting that would need to be changed to reverse the X axis travel.

In the case of my melted Molex connector, I think the wire gage is adequate, but the connectors (2, actually) developed or had a loose connection that created a hot-spot. My original Z connector coming from the controller completely melted & caused the Z motor to stop working. The 2nd failure was the X connector coming from the controller. My X axis started jumping/jerking, and I traced that also to the connector.

Here’s my machine in both configurations:


@Aiph5u it would seem You’re like me …time poor.
@Machinist & @Aiph5u Thanks for the info & links, i wasnt aware that it could be rotated, I just thought the easiest option was for longer cabling.
I wasnt even aware of the manual & i dont recall seeing it mentioned in any correspondence during ordering, but thats not to say there wasnt any mention, probably says more about me.

Thanks for the help & i’m just about to go to the shed & try the rotation process…wish me luck.

I’ll report back my outcome.



Well, I had success in flipping the “X” gantry & even managed to get it all running the right way, so thank you @Machinist & @Aiph5u.

Will test out a cut tomorrow, though i think after repositioning my table & getting all level & square, I may need to run the surfacing code & possibly retram the router, but I’ll see how it goes.

Can you provide some more info i this, perhaps a pic, i couldnt work out where you where referring to, though i do have a journeyman, if that makes any difference

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Hey Moggy,


The Journeyman does appear to have a different nut/oil port configuration (thanks for that pic, @Aiph5u) and perhaps does not require rotation as mine did.

Here’s mine, for reference (front & back pics):

Hey Bill,

perhaps not for fit when flipping the Z assembly, but for access :slight_smile:

Valid point my friend! :wink:

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