Options for Connecting Jammers

[Simon Wilson]

I agree with Mark. A jammer can only take about 400kg so your safety loop does not need to be stronger than that (unless you want it to double as an extra cowstail which I have done in the past).

The one in the photo is 7mm cord. The footloop is 6mm and attached with a 5mm maillon. Because the footloop is free to move around it lasts much longer. The safety cord is protected with tube tape where it is attached to the 7mm maillon and the jammer. Without the tube tape it will always wear out there first. The 6mm loop will outlast several of the 7mm cords.

 

[Fulk]

Mark: If I understand correctly what you're saying here:

The problem is not having enough rope to slot in the chest ascender without it coming out at the bottom at a very sharp angle. If the cam hasn't been closed properly on the new section of rope, the badly loaded chest ascender could release the rope. This situation often happens when the re-belay is some distance from the upper vertical line of the pitch, but, as I said, you would usually have a cow's tail attached to the re-belay anchor point or rope loop for protection.

then as I see it the problem could persist after you've moved away from the rebelay to continue up the pitch. The only answer that I can see for this is to rig an off-set rebelay with lots of slack.

(I did once have a Croll pop off the rope; I was derigging the last pitch of Diccan Pot and had (foolishly?) left a bit of rope dangling beneath me. This snagged on some rocks, and, because the rope was too taut to install a descender, I had to down-prusik on the rope, which was running at something of an angle, in order to free it ? not a nice situation to be in, especially when the Croll popped off the rope.)

 

[Mark Wright]

then as I see it the problem could persist after you've moved away from the rebelay to continue up the pitch. The only answer that I can see for this is to rig an off-set rebelay with lots of slack.

The problem could indeed persist for a short distance if sufficient rope hasn't been incorporated into the re-belay loop during rigging.

If you were using a very worn old style Croll with a sharp edge on the lower edge, poorly rigged re-belay loops (too short) could potentially lead to failure of the rope, luckily below the actual cam so there is a possibility you might survive.

Mark

 

[Disgusted from Cornwall.]

I'm very keen on having my gear set up right and having it nice and simple, effective and efficient.

I don't like rope footloops, or cowstails, purely because they are bulky and naff. I use a thing called an ALP Octopus, which is a triple strap jobby. Short-Long-XL cowstail thing. This attaches to my D Ring (Courdes ally thing) via a 7mm SS Maillon. The XL Cowstail goes to another SS 7mm with a CT Simple hand ascender. I've then got a Petzl foot tape sat over that. It's very neat and very good.

There is nothing worse than dragging a load of rope around with you. It's very 1980s Caving Supplies. Gear has evolved, cowstails and footloops have not (in the majority)

 

[Duncan Price]

DP:

The loop has a figure 8 tied in it part way up from the bottom to form an extra step (like an etrier) which enables me to get higher up towards the top jammer to help with passing changeovers/rebelays etc.

That's an interesting idea; I take it from the very fact that you use it, you don't find a problem with the extra loop snagging. Might I make a suggestion ? an 'in-line figures of 8' (p. 76, ACT) might be marginally better than a standard figure of 8?

It is one big loop split into two (the lower one smaller than the other) by the fig 8. A photo might make things cleared.  Making it out of tape rather than cord would be better.

 

[caving_fox]

I've had a croll pop off mid pitch. It's a bit  but not serious. The knot of my safety line somehow managed to catch the handle just as I was standing up. I'm still not sure how.

Third cow's tail - very useful. I have a very short for rigging, hanging off and tight traverses, and then a medium and a long for normal protection and moving around. I have long arms which helps.

But a normal two piece static handjammer footloop option. Maybe replacing with one longer piece is a better idea.

 

[snoboy]

Making it out of tape rather than cord would be better.

Except tape is more likely to get jammed into your Croll, or so I've heard.

 

[andrewmcleod]

I don't like rope footloops, or cowstails, purely because they are bulky and naff. I use a thing called an ALP Octopus, which is a triple strap jobby. Short-Long-XL cowstail thing. This attaches to my D Ring (Courdes ally thing) via a 7mm SS Maillon. The XL Cowstail goes to another SS 7mm with a CT Simple hand ascender. I've then got a Petzl foot tape sat over that. It's very neat and very good.

Just don't fall on it, because you will definitely definitely die (slightly tongue in cheek, but only slightly - this is assuming it is a sewn lanyard type thing without shock absorption).

Rope may be old fashioned, but a short length of dynamic rope with knots, preferably barrel knots, is pretty much the only way of getting the shock load force from a realistic fall (can't remember if we are talking FF1 or FF2 here; I should check Life On A Line) down below the acceptable safety standard - other than using a shock-absorbing lanyard. I suspect industrial regulations would require shock-absorbers in the system for the purposes we put cowstails through...

 

[mikem]

Alp Design no  longer seem to be selling the Octopus - the description does emphasise DO NOT USE FOR VIA FERRATA (where you can create much greater fall factors). Sewn dyneema will cope with normal fall factors, but knotted dyneema will not...

Mike

 

[Simon Wilson]

In my opinion tape has no place in caving apart from the obvious use in harnesses. Sewn tape is used in climbing because it's light and compact. But the big drawback with tape in caving is that caving gear is subject to wear and tape just can't take it. Tape wears easily and when it does it loses strength very quickly. Dyneema wears less but it has other drawbacks.

Kernmantle ropes and cords lose little of their strength when the sheath wears because most of the strength is in the core. If the sheath is worn but not to the point of showing the core then you can rest assured that it still retains a high proportion of it's new strength. They have a built-in warning system which shows up the wear when they are still within the safety margin.

Slings, cows tails, deviation cords and other stuff made out of kernmantle rope and cord are not quite as light as sewn tape but they are far more robust and versatile in every way.

 

[droid]

Spot on.

 

[mikem]

Depends what sort of abrasion you subject it to, tape doesn't stretch as much to create rub points...

There is no black & white, only shades of grey

Over a sharp edge then metal is preferable; a rough surface, tape may be better than "stretchy" rope.

Mike

 

[Disgusted from Cornwall.]

I've done an awful lot of ropework and all of this nonsense about fall factors is just nonsensical hysteria.

 

[SamT]

For those who sensibly (in my opinion) use a bit of continuous 8mm static for their safety leash/footloop...

One top tip is to use a yosemite bowline for the knot on your footloop rather than a fig eight, the reason being is that its shape holds the loop open, making it much easier to slip your foot in, without recourse to the use of gaffa tape, hose pipe, etc to keep the loop open.

plus its easier to undo if your in extremis and need your 3 meters of footloop rope for something.