UKC

as title - if I needed to use a rope for rigging would an 8mm dynamic rope be ok (I know static rope is usually used but I dont really want to buy another rope yet)

In reply to ow arm:

Yes, but the stretch will mean the rigging point will move back and forth under load. With rock types like soft sandstone that will wear the rock... using multiple strands will reduce rope stretch.

In reply to ow arm:

As long as you allow for the extra stretch in your system when it is loaded it should be ok. If you are belaying from a dynamic system/anchor point for example, you may risk being pulled off your stance if there is unexpected stretch when holding a fall.

In reply to ow arm:

Due to the stretch, the anchor point could move around on the rock encouraging erosion of the crag and potentially doing damage to your rope.

It comes down to how often you will be using it. 11mm diameter statics are great for regular use due to their durability. An 8mm dynamic may not be as durable long term and you may end up buying two new ropes rather than just one.

In reply to ow arm:

Protect on edges to stop the stretch wearing the rope unnecesarily

In reply to ow arm: It depends...

The static elongation of 8mm ropes is pretty large but it also varies considerably between individual ropes.

For example, if your rope is a Beal Iceline (probably the stretchiest rope ever made) and the anchors are far back then it certainly wouldn't be great. However if your rope has lower stretch, the anchors are close or you can use double strands than you probably won't have too much of an issue.

FWIW Mammut 10.5mm semi-static will only stretch around 2.8% under bodyweight but an Iceline 8.1mm dynamic will stretch 11.5% - FOUR times as much!

In reply to ow arm:

thanks all - seems a very consistent response

I dont think id need to use it often otherwise would definately purchase a static rope, and would use it doubled to reduce stretch also.

In reply to ow arm:
Do you have a specific spot in mind? Any idea how much rope you need?

There's probably no need to buy a 50m (or whatever) rope, you can buy it by the meter.

In reply to ow arm:

Depends on the situation. I've never used static rope for rigging an ab. You can buy static by the meter and just get 15 metres, that should be sufficient for most situations and not heavy to carry.