Tool to quickly wind/twist two cables around each other

[Brumby]

Where's the fun in that?

[Psi]

Sureiy it'd be easier to just buy some twisted pair cable and deal with the sheath?

I did look into this, but it was more expensive than two 100m reels of single cable.

[Ian.M]

... but less expensive than the time at minimum wage to hand-twist it!   

How long is the required twisted pair, what wire gauge and strand count, and what's the O.D.   Also how many of these do you need per day/week/month or other time period.

[Monkeh]

Sureiy it'd be easier to just buy some twisted pair cable and deal with the sheath?

I did look into this, but it was more expensive than two 100m reels of single cable.

Well, yes, you have more material and several more production steps.

Upside: You can just use it.

[suicidaleggroll]

I've tried various methods using a drill, but as others have already said, if the wire is just 'twisted' then it always un-twists as soon as you remove the tension.

Only a very small amount.  Keep it from ratsnesting while it untwists with your hand and you're set. 95% of the twisting you put in with the drill will say there.

[Ian.M]

The odds are I've hand twisted more yards of wire than any other member here.

Way way back when I was a kid, I used to make 100 yard long twisted pair cables from fairly fine magnet wire for a field intercom I'd designed and built   The cables were basically disposable - if they were just thrown out on grass you could probably re-spool them, but if they were concealed the odds of retrieving them without a break or insulation damage was near zero, so I made a lot of them that summer.   Twisting >100 yards of wire when the garden was only 30 yards long, without power tools (no battery drills back then) was quite a challenge.    I had two spools, one screwed vertically to a post, loaded with about 120 yards of two strands of magnet wire, and the other with a bolt through the middle chucked in a hand drill.   There was a padded clip for the wire under the bolt head.    The procedure was to spool off 30 yards or so from the fixed spool, diagonally across the garden, knot the end and attach it to the spool in the drill chuck, leading the wire through the padded clip.  Then I'd furiously crank the drill, while maintaining a steady light tension till I liked the look of the twist, then ease off the tension and wind back till the wire no longer tried to kink, run to the other end and unclamp the fixed spool so it could spin with a drag, run back, remove the wire from the clip and with the drill held sideways, crank it to wind that length onto the spool till I was close to the untwisted portion, put it back in the clip, re-clamp the fsr end and repeat untill it was all twisted.

I also did about 100 yards of stranded PVC insulated wire that way for an intercom from the house to an outbuilding that we used as a workshop. - that was a royal PITA - it was far harder to get it to twist evenly and to avoid kinking.   All this was before 10BASE-T Ethernet so twisted pair was expensive and difficult for a hobbyist to acquire if you didn't have a friend in the tech side of the phone company.

Would I do it again the hard way for longer than I could stretch from the vice along my workbench?  Hell no.  I rarely use an twisted pair that isn't stripped from Cat5 or 6 Ethernet cable or patch cord, and for the few occasions when I needed low voltage power with minimum magnetic field and bare stripped UTP wasn't good enough, I rewired with small OD coax.

[tautech]

As Psi needs it for auto sensor application I understand his concerns and need to use the correct cable that's best suited for this type of usage.
I keep having thoughts of using a quality ball bearing type game fishing swivel attached to a vertical board for the dead ends to help negate the reverse twists as the pair are being wound together. What the connection scheme would be I don't know, maybe some small angling split rings to alligator or bulldog clips and a knot or crimp at the driven end. Cut short lengths of ductile metal tubing could provide a source of crimp sleeves for hand or vise closure which will be snipped off after the twisting process.

[Ian.M]

You can buy unshielded CAN Bus cable, with automotive rated insulation you know isn't going to quickly go brittle or turn into goo in the engine compartment environment.

OTOH I think your fishing swivel idea has merit.   Open up a pair of screw eyes and re-close them after attaching the swivels then screw them into the board.   Simply knot the wire through the swivels, and cut it to detach the twisted pair.   For the drill chuck end, a figure-8 knot is good - it provides enpough thickness for the chuck to grip.  For thin or thick wires, you'd do better to knot them to an eye bolt and chuck the stem of that.

[Psi]

... but less expensive than the time at minimum wage to hand-twist it!   

How long is the required twisted pair, what wire gauge and strand count, and what's the O.D.   Also how many of these do you need per day/week/month or other time period.

Total wire length 1.5m
Qty, about 10 a week.
24AWG
The twist ratio i don't care about, ~1 per inch would be fine

[Ian.M]

I'd try Tautech's ball bearing fishing swivel suggestion for the fixed end, and a variable speed battery drill with a small eye bolt in the chuck to attach the wires to.  24AWG solid core should hold a twist pretty well with minimal sping-back, if you force it to twist near the chuck first by separating the wires with a polished steel rod that you slide towards the fixed end while the drill twists the wires.

Its probably manageable as a one man job with a little practice and the fixed end fitting clamped in a bench at the right height so the drill can be held with the base of its battery pack flat on the bench. You'll need to practice to get sliding the rod coordinated with the drill control and learn how much excess length you need. 

OTOH, given enough space, doing it as a two man job with one person controlling the drill and the tension and the other walking towards the fixed end sliding the rod would be a lot easier and would let you do several lengths in one piece..     

The weekly quantity you need is possible - if you don't mind the labour costs which I would estimate to be of the order of $10 per piece twisted and cut, before termination.