How to braid cables

Making cables into braids

There are various ways to route cables neatly; and also various ways to keep multiple cores together.
This article will focus on the latter task; and in particular, the least-used yet perhaps most elegant method.

Overview of various cable management techniques

While there may be others, I’ve listed the sensible methods as well as a few which are obvious-but-not-recommended:

Advantages Disadvantages
Adhesive tape Cheap, cuttable to any length. Prone to unsticking (especially in hot locations and with poor-quality adhesive).
Leaves residue on the surfaces.
“Zip” (ratchet) ties Cheap, easy to apply.
Also useful for securing cables to structures.
Difficult to remove (some types are available with a pull-tab which mitigates this somewhat). The ratchet end can get caught on other items.
Can press through the insulation if over-tightened. Off-cuts are wasted (not good for much else). The cut end can be a bit sharp.
Twist ties (you may also use off-cuts of any other sufficiently rigid wire) Cheap, easy to apply and remove.
Also useful for securing cables to structures.
The steel wire inside can pose a short-circuit hazard if its ends touch circuitry.
Velcro (hook-and-loop) straps Easy to apply and remove, no metal component to cause short circuits.
Extra length can just be wrapped around again.
Can catch on each other. (However, this could also be used to advantage)
Usually wider than zip or twist ties. May attract dust and dirt.
Ribbon cables Cost-effective to manufacture (almost no extra material required).
Low profile ideal for laying in shallow spaces (such as behind the mainboard tray).
Not applicable as a DIY modification (unless you replace the whole cable with a ribbon).
Can’t flex sideways (with the ribbon in horizontal plane), so may have to twist to make certain turns.
They get unwieldy (and impede airflow) when they have a lot of cores and become wide (>20mm or thereabouts).
Woven sleeving (overall)
Keeps the wires together for the whole length of the sleeve (rather than just at intervals). Can add stiffness. Can’t be added over the cable assembly ‘in-situ’.
Ends of the sleeve must be covered (usually by heatshrink, see below) to prevent fraying.
Heatshrink tubing Conforms to the diameter of the wire bundle beneath.
Also provides electrical insulation (good for protecting wire splices).
Adds stiffness. Can’t usually be added over the cable assembly ‘in-situ’, unless you get a piece with a high enough shrink ratio to slide over the connectors and then still shrink onto the wires underneath. Requires a heat source (usually a heat gun), which can be hazardous if set too hot.
Twisting the wires together No material cost. Can untwist, especially if you just tried to twist the whole assembled cable together.
Braiding No material cost. Can’t untwist, maintains reasonable flexibility if done properly. Requires at least 3 cores, and access to their individual ends. Somewhat poor space efficiency.
Can be laborious to make by hand.

Not included in this table:

  • “P” clamps: Good for securing cables to structures (provided you have a place to insert the mounting screw), but not applicable to keeping the cores together elsewhere.
  • Sleeves over individual wires: These don’t actually keep anything together, so don’t really count as a cable management technique.
    Frankly, I wonder how anyone manages to bend power cables (especially the 24-pin main ATX) with that “treatment”…

There are also arguably-superior variants of some material items, such as self-amalgamating tape.

Electrical considerations in cable management

DC power cables generally require no special attention to their core arrangement (beyond keeping the terminals in their correct positions, and of course not damaging the cable).

Fan motors draw significant ripple currents, so it’s good to keep at least their power wires (+ and ground) together to limit EMI. If you need to extend their wires beyond the original factory length, I would also recommend adding a capacitor (10μF ceramic works well experimentally; if electrolytic, use low ESR) at the join, to limit the length of cable carrying the ripple (at least the high-frequency components); bear in mind however that this will be incompatible with power-side PWM (which was a common kludge available on old mainboards with only 3-pin fan headers, although it had the drawback of corrupting the tachometer signal). (Some fans do have their own capacitors built-in, although these may be rather small electrolytics and therefore of limited help.)

Some data or other high-frequency signal cables have the wires in a specific arrangement to ensure the proper electrical characteristics, and rearranging them will have unpredictable results (possibly causing errors).
Most modern (SATA, SAS, USB etc.) data cables are shielded anyway (so you won’t be rearranging their cores even if you wanted to), but prevalent examples included 80-wire PATA/IDE cables (the original 40 wires were interleaved with an additional 40 ground wires to suppress crosstalk between the data lines) and SCSI ribbons for single-ended signaling (same principle with most of the odd cores as ground; the later differential cables forming the data lines into twisted pairs). Even the 34-pin floppy drive cables had a similar arrangement (all the odd wires were ground), although they were far more forgiving given the low speed.

There may be other arrangements too; but the key point is, don’t alter the formation of signal/data cables unless you know the details.

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