In this article, we're going to cover traditional access on an SRT line using a microfrog system.
We'll be installing an access line and setting a midline anchor point by using s pulley, attached to the access line partway up the tree.
This can be advantageous if all you need to do is climb out along one limb. For example, you don't need to climb all the way to the top of the tree. And you also have the advantage of having a high anchor point for going out on a limb.
You also you don't need as much rope in your DdRT system. So this gives the benefit of the high anchor point but using an SRT system to access it. With a DdRT climbing system.
SETTING UP THE MIDLINE DDRT SYSTEM
You will need to pull a decent amount of slack into the SRT access line to tie an alpine butterfly partway up the SRT line. Clip a pulley onto the alpine butterfly - in our case, we're using a DMM pinto rig. Install a short climbing line through this and loosely tie the rope off to stop it pulling up the tree as you raise the access line back up.
As you are pulling the access line back up, the double rope climbing system will be going up with it. Pull it just up above the limb you want to access and now you'll need to SRT up there.
ASCENDING THE ACCESS LINE
So we've installed our SRT line with a midline pulley set just above the limb which we need to work on and I've installed our doubled rope climbing line on the system with the hitch climber system.
To ascend the access line, we going to be using a microfrog frog walker system. Using a Kong Futura as our hand ascender, along with a Petzl Basic as our body ascender - this means that we have a "half a point of attachment" (hand ascender) and another "half a point of attachment" (body ascender), for one "full point of attachment". And then also a foot ascender. We'll also be using a neck elastic to progress the body ascender.
Set a bit of base weight in your access line to assist with the climb, take a bit of tension up on the access line, clip in, and add the foot ascender. Then start ascending to the point that you can add on the footloop. Tension that up and off we go.
TRANSFERING ONTO THE DDRT SYSTEM
So after ascending on the traditional SRT line, clip into your DdRT system.
All you need to do then is make sure that you detach your neck elastic from the body ascender to stop it creeping up, then lift your weight out of the ascenders with the doubled rope system and then completely transfer over on to it.
CONCLUSION
So we have just gone through SRT access using a microfrog ascender system and setting a midline anchor point for a double rope climbing system. So access on a microfrog and climbing system off of a midline attached pulley for DdRT climbing.