## / Tyrolean traverse setup

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Looking at setting up a tyrolean traverse between two artificial climbing walls. Has anyone tried this? As trying to work out a setup. Would be at the top between the two towers, there is a walk way that will be running parallel. There is a bar at either end, where be anchor top ropes at the moment. Would be need more anchors at the top.

Def check the anchors. Different forces involved
In reply to ice.solo: Not just different, but rather more substantial forces involved, anyone who's tensioned a slack line against a seemingly secure object (say a lamp-post), or equalized gear for an anchor using too short a sling (and lived to tell the tale) will have first hand experience of this...

This explains quite well: http://www.chetwynd.info/other/anchors.htm

According to the formulas with an 80kg person in the centre of the traverse, rope straight between the two anchors and minimal rope/cable stretch the anchors would be experiencing in the region of 1130kg (11.1kn) each, and the rope/cable would be experiencing double that... 22-26kn is the kind of breaking strains I found by doing a straw poll of several brands of (10.5mm) static rope*, so you'd have a very small to totally negligible safety margin.

*with 12mm things get a little better with upto 36kn braking strains available, which may be all right, but it's a comparatively specialist product.

As mentioned, the load on the anchors can be massive, though it reduces by the bigger the sag you have in the line. (which can then create the problem of too much sag if you reduce the angle too much).

I think the optimum angle is 150 degrees at the centre (taking a completely horizontal traverse line to be 180 degrees:- i.e. 15 degrees off horizontal at each side). But this still puts double the weight of the load on each anchor.

Have a look at this groovy little calculator to show the effect on the anchors at different angles. Adjust the weight you want at the bottom and move the wee weight up and down to alter the angle and it shows you the effect the different angle has for whatever weight you select:

http://www.tagsafety.com/library6.asp

In reply to crc1982: If you remember the company a few years ago that we're running a dodgy zipline at Burbage one of the outcomes was that they wouldn't have been insured as this kind of rigging isn't covered by SPA or any other climbing instruction award.