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rope twist when using alpine coils

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 maxsmith 13 Oct 2021

Hi all, I do a lot of roped scrambling and I'm getting increasingly frustrated by mega rope twist.  I usually use 40m of 9mm ish Mammut rope which is quite twisty but over the weekend my partner and I used 30m of 8mm ish Mammut which was insanely twisty.

The climbing was typically a mix of: moving together with 15m coiled on the body and 15m live, pitching with 30m live or soloing with 15m coiled on the body and 15m coiled on top and tied off 'soft'.  By the end of the day we were so frustrated by twists that we resorted to flaking the rope from top to bottom every time we shifted from one climbing style (i.e. soloing/moving together) to another.

Couple of questions: 

Is it true that a thinner rope will always be more tangly than a thicker one?

With longer ropes I reduce twisting by using the 'butterfly' coiling method.  I'm guessing alpine coils are part of the problem, so is there an equivalent 'butterfly' way to take (or remove) alpine coils?

Thanks for any help

Post edited at 12:59
In reply to maxsmith:

The twists occur because for each coil that you take, you put a half twist into the rope — and with alpine-style coils, all of the twists are in the same direction and so don't 'even out'. No idea on a practical solution — taking coils in the opposite direction every time you drop them might help?

You're putting the same amount of twisting into the rope whether it's thin or thick, but previous experience suggests that the thinner one will be more susceptible to twisty tangles.

 gravy 13 Oct 2021
In reply to tehmarks:

You get a twist for every coil, practice carefully uncoiling in the opposite way you coil to get in the habit of untwisting as you lift off. Assuming you both tie on first with an untwisted rope then coil and uncoil carefully then you can't get any net twist in the rope unless you or your partner turn around.

The worst thing you can do is to coil without being tied on at both ends and then for your partner to tie on because all the twists are there in there rope coil and it can't untwist by rotating at the ends.

Get in the habit to both tying on before coiling and always uncoiling in the opposite manner to the way you coil.

If you dump the coils on the floor (rather than uncoiling) and then just take the rope you're asking for trouble especially if you tie on after.

Butterfly coiling from the middle ensures any twists in one end are balanced by a negative twist in the other so the net twistiness should be zero (although our intrinsic handidness and less than perfect coiling means we often put in little twist on average but this usually works itself out). This doesn't help much for alpine coils.

My experience is thinner ropes tangle much more readily when twisted.

Personally my main problem is usually "turning left" when I sit to belay (facing out) and then "turning left" when standing to face in and climb which tends to add a twist a pitch (which shows up nicely on double ropes).

 maxsmith 13 Oct 2021
In reply to maxsmith:

thanks both, I typically coil while my partner is not tied in and never uncoil (I just throw the loops on the floor) so that looks like the problem.

Can you explain this again in a different way? Can't get my head around it, it seems really counter-intuitive.

The worst thing you can do is to coil without being tied on at both ends and then for your partner to tie on because all the twists are there in there rope coil and it can't untwist by rotating at the ends.

 nniff 13 Oct 2021
In reply to maxsmith:

Roadie wrap - over-worked and under-paid. Google/youtube

Like a trucker's hitch/haulier's hitch - things you need to know to get by in life without twisted cables, hoses, alpine coils or loose loads on roof racks

 maxsmith 13 Oct 2021
In reply to nniff:

thanks, I've tried this 'over-under' coiling technique and found it much, much slower than traditional alpine coils.  But maybe it's the only way that allows you to just drop all your loops on the floor without uncoiling?

 Mark Haward 13 Oct 2021
In reply to maxsmith:

I've never really thought about it before your post but, on reflection, each time I make a coil over my head I roll the rope a half twist towards the back of my neck ( if that makes sense? ) and focus on ensuring the coils are even and neat. If I remove some coils I tend to remove them one at a time putting a reverse half twist as I remove each one. This sounds slow and clunky but actually I do it pretty quickly and instinctively. I've never had a problem with twisty ropes using anything from 8.5 - 10.5 mm ropes. Of course, perhaps I've just been lucky!

 gravy 13 Oct 2021
In reply to maxsmith:

"Can you explain this again in a different way?"

> Each time you put the rope over you head you put a twist in the rope in the coil. <

This is key - the rope in the coil doesn't look twisted but if you straighten it out without uncoiling you will see that the coils=twists [try wrapping a bit of ribbon around a rolling pin and then removing the rolling pin and pulling straight, one twist per turn].

So if you make 10 coils, drop on the ground then tie in and pull the rope straight you have 10 twists. Repeat a few times (bearing in mind you're probably "handed" so will probably coil with the same added twist each time) and you'll soon have loads of twists and the rope with tangle like a bastard.

If you both tie in first you cannot have a net number of twists unless one of you turns around so the +10 twists in the coil must have -10 twists in the rope between the two of you*.  When you uncoil these all go away.  If you drop the coils and straighten you'll end up with a mix of + and - twists which will cancel each other out as the rope is pulled through and the twists won't accumulate a make tangles.

Hence the 2 top tips: both tie in first (ensure no accumulation of twists) and uncoil rather than drop (ensures twists are undone).

* there is a tendency to let the rope rotate in your hand as you coil so the -ve twists in the loose rope tend to get carried through to the coil so  in practice you end up with something like 5-ve twists in the loose rope, -5 twists in the coils and 10 coils which would make +10 twists if you pull it out.  Net twists 0 assuming the ends can't rotate (ie you are tied on).

Do the ribbon test - it's much easier to try it than explain it!

 nniff 13 Oct 2021
In reply to maxsmith:

Yes, it's a bit slower at the time, but overall it's quicker.  Like all these things, practice helps

 Will_he_fall 13 Oct 2021

As others have said, if you make sure to always drop the coils off one at a time this will solve your twist problems. 

I regularly take coils before tying on the other person on the rope and don't find that this causes a problem. 

 Misha 13 Oct 2021
In reply to maxsmith:

If you just dump the rope on the floor instead of uncoiling loop by loop, that’s your problem. You get rope spaghetti anyway so it’s actually quicker to uncoil loop by loop.

I’ve never thought about whether it makes a difference whether the other person is tied in or not. The real point is they should tie in as soon as there’s an end free, otherwise they’re wasting time (unless they’re doing something else useful). 

 Mike_Gannon 13 Oct 2021
In reply to maxsmith:

We had this problem when I was a lifeguard. The trick is to hold the rope between your thumb and fore finger and apply a small twist as you coil the rope over your head.

You need to practice to get the twist in the right direction, but you should find that the twist encourages the rope to kink in the right direction. The wrong direction and you'll notice the rope resists wrapping neatly.

Good luck.

 maxsmith 14 Oct 2021
In reply to gravy:

thanks, still struggling to get my head around why being tied in is better, but i'm sure you're right! by the way you are some sort of zen level rope master - respect

 gravy 14 Oct 2021
In reply to maxsmith:

Try this:

Take a length of ribbon, fix the ends with tape to something and then twist the middle - you create + and - twists either side of the middle. Once you let go of the middle and ribbon relaxes the + and - twists cancel each other out. 

This is what happens if you are both tied in before you coil - no matter how badly you treat the coiling process the total number of twist is the rope remains zero because the ends of the rope cannot rotate*. Local twists will eventually find their opposite twist and disappear.

I think the problem you face is making the same mistake several times - this builds up the overall number of twists in the rope until it starts kinking at which point it turns into a tangly mess.

*Unless one of you turns around.

Post edited at 08:39
In reply to gravy:

Yes but in practice the other half of the rope is either static on the floor or tied into another person. Whether it's actually tied makes no difference, it's not moving relative to your coils.

 gravy 14 Oct 2021
In reply to Suncream:

That's not quite correct. 

If you keep repeating the process the loose end of the rope will rotate as twists work their way off the end of the rope - this leads to a build up of twists in the rope especially if you flake the loose half after the colis are taken. 

This is a common scenario - butterfly coils are dropped, first person ties on, takes chest coils, leaves a mess on the ground, 2nd person flakes the remaining rope to clear up the mess and find their end. In the process a few twists work their way out off the end, result the rope as an unequal number of + and - twists and the result is the rope has a few net twists.

People tend to repeat the process in a handed way, eg always putting the coils over their right shoulder so the same direction twists keep getting added and over time your nicely behaved rope turns into a mess of knots.

Much the same way corded telephone cables twist (pick up right hand, transfer to left hand put phone down, one anticlockwise twist every time the phone is answered).*

* you might have to be over 50 to remember phones with cables!

 maxsmith 14 Oct 2021
In reply to gravy:

got it now, thanks for explaining again

 gooberman-hill 15 Oct 2021
In reply to maxsmith:

When you take coils (for whatever reason), if you use a front/back method you will even out the twists.

When you take the first coil, you place the loop in front of end. The second coil is looped behind the first (so the twist goes in the opposite direction), the third then goes in front of the first, the fouth behind the third, the fifth behind the fourth. So odd numbered loops go at the front, even numbered loops go behind the front loop.

If you coil like this, then you can throw the rope out and it will uncoil smoothly without twisting.

I learned this method coiling audio cables on stage and in a studio.

Steve

 maxsmith 15 Oct 2021
In reply to gooberman-hill:

but do you use this method when taking alpine coils over your head? I've tried and found it too fiddly...


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