Installing a climbing rope over an anchor point
With the throwline set in the target union , the throwbag can be removed from the string line and the climbing rope can be attached .
If the climbing rope is spliced , the string line should be tied directly into the splice using a bowline or similar knot .
If the climbing rope is not spliced , the throwline should be attached using a clove hitch tied approximately 300mm back from the working end of the rope , followed by a series of half hitches made between the clove hitch and the working end .
The series of hitches should be dressed neatly and set prior to pulling the line into the tree .
If there is any concern that the lines may become separated , it may be helpful to tie a second clove hitch as the last knot at the working end , or replace the last half-hitch with a marline hitch to prevent slipping .
Installing multiple ropes
Where multiple ropes ( e . g . a climbing line and safety line ) are to be installed over the same anchor point , a single throwline can be used to install both ropes .
It is not recommended to immediately attach two rope ends to the throwline , unless the target union is clearly open , smooth and free of obstacles . It is sometimes tricky to pull a line through a tight fork ; two ropes together could easily get stuck , wasting the original shot .
The following are preferred options to install multiple ropes :
1 . Use the first throwline to install a second throwline , then use each throwline separately to install one rope . If either rope gets stuck , the other line may still be functional .
2 . Tie the throwline to the midpoint of a rope which is at least 4 times the height of the anchor in length . Pull up the mid-point and tie off using two alpine butterflies or similar .
3 . Install one climbing rope as shown above . Use the first rope to install a second . This will allow the rope to be pulled more aggressively through the target union than is possible with a throwline . If the joined ropes will not pass the union , the team will at least retain a single useable access line .
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