Single, Double, Twin

Ken Carrara wrote:I leaning towards the Mammut genesis myself. I just wish it was available in 8.5x70

i own the 70m phoenix myself ... and in most cases you dont need the 70m ...

the only time i use the full 70m is when linking pitches (and this one time we missed a station but could reach another station with a 70) .... which with 2 newish followers can be problematic

most raps are set for 60m and below ...

though if you do need to chop them the 70m would be useful

;)

I guess the extra 10m is often more trouble than it's worth

bearbreeder wrote:...also you might have issues finding partners who are well versed in double belaying ... in that case youre better off using them as twins, which is fairly easy to teach

Although you lose the efficiencies of one person belaying and one person tending to the ropes, I've still found it generally effective when climbing using half ropes with two followers to have each follower belay on one of the ropes.

Thanks for all the input. I have narrowed it down to the Mammut 8.5 Genesis or the 8.7 Serenity.

I just bought an 8.9mm 70m Elderid rope. I got the 70m because with it being 8.9mm, its really light already, an extra 10m only adds 520g. There are numerous 35m rappels in the world, or at least rappels where a 70m makes it less sketchy (Grand Teton rappel) so its not like I won't use those 10m.

Not to dredge up an old thread, but I just want to double (pun) check this before I go use it in the wild (Grand Teton) this weekend.

It is perfectly OK to use a single strand half rope to rappel in a blocker knot and tag-line setup? I know the rap will be quick with just one strand of an 8mm Phoenix, so I'll throw an autoblock on there too, but juuuust double-checking. I heard that even off the main rap on O/S on the Grand you can use a single 60m just fine but you have to chuck it to lookers left.

Kyle Tarry wrote: Do you have a link to a source for this? I question the validity of this, but it would be good to know if it was the case. Generally, if you're employing standard half technique, when you fall you're only falling on one rope anyway, so I don't see what the relative stretch would be that relevant. I think it depends on what you want and how you plan to use the rope, but for what you've described I don't think it's necessary. The single rating is specifically for leading on it, so if you're not going to do that, there's no reason to pay the money and carry the weight. I could see using a single/half rated rope for alpine/mountaineering where it's mostly low angle but occasionally you need to lead a steep section on it. That being said, I do this on a half rope and don't feel bad about it.

Kyle's response to the previous post with this quote:
"flag Stering Nano IX 9.0 rated as a single, half, and double. Plus the Sterling Fusion Photon 7.8 rated as a half and double. "

In reference to using them as (edit - see below) TWIN ropes, they will both be going thru each pro biner and laying one on the other. In the case of a fall, one stretches more than the other. This causes friction of the ropes, a potential melting of the sheath, and potential burn and break of one line. I will try to find the source for the record. It is the same reason we put biners or rap rings on slings, etc.

I just wanted to clarify for safety sake that using two different ropes for (edit - see below) TWINS is not recommended. Anyone have that link? In general, if I use anything other than single or tag my ropes will be the same model and age. Good thread.

Edit addition: OP - if buying two new ropes, I would get the same model/length/etc on general principle. Again, see Kyle's comment below.

Faulted Geologist wrote:In reference to using them as double ropes, they will both be going thru each pro biner and laying one on the other.

If you're using them as doubles (half ropes is the "correct" term), and you are putting both of them through each carbiner, you are doing it (very) wrong. Half ropes go through the gear in an "alternating" fashion (thought not strictly 1:1), with only one rope clipped into each piece.

Faulted Geologist wrote:It is the same reason we put biners or rap rings on slings, etc.

I think that this is a red herring. The loading and motion is very different when lowering off a rope on a piece of cord.

Faulted Geologist wrote:I just wanted to clarify for safety sake that using two different ropes for doubles is not recommended.

Sounds like you're confusing half and twin ropes, which is a much greater risk to safety than using 2 different half ropes.

Kyle, you are right. This is a common syntax error I have done before. The terms are slightly confusing. Twin - one rope path up, and half ropes go separate paths. I should have 'double' checked this given my past confusion. Editing my post above to reflect this. I think the original quote on page 1 was intending to reference twin ropes of different diameters and making the same syntax error.

Both rope designations are four letters long. Twin and Half. Frack the word double. Good memory key. They are BOTH double rope setups, HALF & TWIN.

Can the OP or Admin edit the thread topic header? Maybe that is where today's syntax fudge came from. Prob not if it gets incorporated in the url.

Tony T. wrote:Not to dredge up an old thread, but I just want to double (pun) check this before I go use it in the wild (Grand Teton) this weekend. It is perfectly OK to use a single strand half rope to rappel in a blocker knot and tag-line setup? I know the rap will be quick with just one strand of an 8mm Phoenix, so I'll throw an autoblock on there too, but juuuust double-checking. I heard that even off the main rap on O/S on the Grand you can use a single 60m just fine but you have to chuck it to lookers left.

If you have a half-rope setup, then you should have two half ropes. The second should be your 'tag' line. Ditch any other small 6mm-ish tag. Did I read this right?

Faulted Geologist wrote: If you have a half-rope setup, then you should have two half ropes. The second should be your 'tag' line. Ditch any other small 6mm-ish tag. Did I read this right?

Ah, I wasn't very clear about this (and the terminology is a bear to get straight).

I have 8mm Mammut Phoenix ropes, which are rated as both half and twin. I was under the impression that I could use a single one of these ropes to rappel, so I wanted to double-check if it was safe enough to tie a 6mm tag-line and a blocker knot and rap down it, or if there is some safety consideration for rapping off the middle mark instead.

Thanks!

Rapping on an single 8 mm half/twin is totally fine. I simul-rap on my 8.6 mm halfs all the time.

Note that, as you said, there will be less friction. An autoblock will not help that. You may want a second biner in the rap device to add friction.

Kyle Tarry wrote:Rapping on an single 8 mm half/twin is totally fine. I simul-rap on my 8.6 mm halfs all the time. Note that, as you said, there will be less friction. An autoblock will not help that. You may want a second biner in the rap device to add friction.

Kyle, help me understand what OP is saying. I commented that having a tag line when carrying a half or twin setup is pointless. I hadn't thought about simul-raps, which requires two tag lines for full length raps. Do you climb with two half or twin ropes and two tag lines for full length raps? Why not just ditch the tags and take turns down to save that weight? I am sure there are situations where the two tag lines would be convenient, but the added weight and bulk seems pointless. To be upfront, I am still learning the ins/outs of double rope setups.

Tony T. wrote:Not to dredge up an old thread, but I just want to double (pun) check this before I go use it in the wild (Grand Teton) this weekend... I heard that even off the main rap on O/S on the Grand you can use a single 60m just fine but you have to chuck it to lookers left.

Don't bother taking a tag line or two ropes up the OS on Grand Teton. A 60m 8 mm rope is just right. I took one 60m 8.2 when I did the (complete) Exum, and found that this was plenty for both the climb and descent. I wouldn't have wanted any more rope weight than that. The OS has much less technical climbing, and the same descent, so a minimal rope setup is just fine. There is a way to rap with a 60, but make sure you get the beta before going. We got the info from Mountainproject and it was easy to figure it out just fine. Be careful up there...winter is coming.

JCM wrote: Don't bother taking a tag line or two ropes up the OS on Grand Teton. A 60m 8 mm rope is just right. I took one 60m 8.2 when I did the (complete) Exum, and found that this was plenty for both the climb and descent. I wouldn't have wanted any more rope weight than that. The OS has much less technical climbing, and the same descent, so a minimal rope setup is just fine. There is a way to rap with a 60, but make sure you get the beta before going. We got the info from Mountainproject and it was easy to figure it out just fine. Be careful up there...winter is coming.

What he said.

Whatever you choose, DO NOT BUY TWIN ROPES!!!!!

They are a huge pain in the butt. I have had good luck with a 60 or 70m skinny rope (Sterling Nano) and if I want full length rappels, the second carries a coiled twin rope in a pack.