Author Topic: Would you...  (Read 1099 times)

Offline Madness

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Would you...
« on: November 30, 2019, 11:06:56 pm »
...abseil a 50m drop if your only anchor was a stainless steel wire rope with swaged eyes passed around a bombproof formation. The swaged eyes have stainless steel thimbles. The eyes are secured with a bright zinc plated Maillon, which is also used for threading the rope for a retrievable abseil. Swages/ferrules are aluminium.

We've all seen a aluminium krab decaying on a stainless anchor. So, what's happening on the inside of those swages/ferrules where aluminium and stainless steel are in contact?

I'd be interested in peoples opinions .

Offline Greg Jones

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Re: Would you...
« Reply #1 on: November 30, 2019, 11:24:13 pm »
Initially I would have said yes, but once I realised that you were talking about something that had been in the cave a while then maybe not. I'd rather cut a metre off the rope.
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Offline nickwilliams

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Re: Would you...
« Reply #2 on: November 30, 2019, 11:36:02 pm »
Stainless wire rope should be swaged with copper ferrules, The rest of the system should all be stainless with no dissimilar metals in contact with each other.

Having said that, if the swage is properly done it should not have any cavities where water can penetrate and there won't be any electrolytic corrision if there is no water.
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Offline Madness

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Re: Would you...
« Reply #3 on: December 01, 2019, 08:04:10 am »
It's the fact that you can't tell what's happening on the inside of the ferrule that concerns me. Is it all turning to mush from within?

Offline blackshiver

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Re: Would you...
« Reply #4 on: December 01, 2019, 05:55:22 pm »
I have a plan so cunning you could pin a tail on it and call it a Weasel.

Offline droid

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Re: Would you...
« Reply #5 on: December 01, 2019, 06:11:24 pm »
My attitude was always: if in doubt, don't use.

Unless I *had* to.... :'(
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Offline Madness

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Re: Would you...
« Reply #6 on: December 01, 2019, 10:13:01 pm »
This is not a hypothetical situation. The only detail I changed was that the cable is around a tree and not a formation. It's the main abseil off High Tor in Matlock Bath. The thread about the recent abseiling accident brought it to mind.

For those who have never done this abseil, it's feels exposed and committing. The last thing you want to worry about is the integrity of the anchor, especially when passing Castellan Cave.

Offline Bob Mehew

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Re: Would you...
« Reply #7 on: December 01, 2019, 11:00:03 pm »
It's the fact that you can't tell what's happening on the inside of the ferrule that concerns me. Is it all turning to mush from within?
Simple answer - yes in time.
It's the main abseil off High Tor in Matlock Bath.
Don't DCA publish a list of items they keep under their care?  It is not immediately findable on their web site however.


Offline Madness

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Re: Would you...
« Reply #8 on: December 02, 2019, 08:13:11 am »
Don't DCA publish a list of items they keep under their care?  It is not immediately findable on their web site however.

It's not a caving anchor, but a climbing one. DCA will have nothing to do with it. I don't think the BMC install or maintain anything, so I suppose it's down to individual climbers to check/maintain. Trouble is, I suspect most climbers see this big stainless steel wire rope to abseil from and just assume it's bombproof.

Offline paul

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Re: Would you...
« Reply #9 on: December 02, 2019, 12:04:57 pm »
BMC do install abseil anchors, for example at Harrisons Rocks near Tonbridge Wells, which is BMC owned. High Tor is managed by Derbyshire Dales District Council so I doubt that in this case it was installed by BMC.
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Offline Addy

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Re: Would you...
« Reply #10 on: December 02, 2019, 12:34:56 pm »
... and those BMC installed  anchors at Harrison's, High Rocks, and Bull's Hollow, along with the anchors installed by Bowles Rocks are regularly checked. They are also intended for Top-Roping and not abseiling (which is banned on the sandstone outcrops).

The BMC have also installed anchors and many other quarries and I suspect they are regularly checked as well...

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Offline RestingCaver

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Re: Would you...
« Reply #11 on: December 03, 2019, 04:29:39 am »
The single point of attachment issue is the biggest one for me.

Offline Roger W

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Re: Would you...
« Reply #12 on: December 03, 2019, 12:18:33 pm »
The OP does refer to a "bombproof" point of attachment - later identified as a tree.  I presume the said tree is fairly firmly set in the ground.

I must admit that the idea of being in free fall down a cliff face and followed by a large tree attached to me by a length of rope doesn't altogether appeal to me...
"That, of course, is the dangerous part about caves:  you don't know how far they go back, sometimes... or what is waiting for you inside."   JRR Tolkein: "The Hobbit"

Offline markpot

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Re: Would you...
« Reply #13 on: December 03, 2019, 09:23:56 pm »
I have....quite a few times(abbed off the anchor in question).i know where mad is coming from and have asked the same question myself. Single ab points,trees ect are regularly accepted as bomber as descents from climbs.i cant think of another in the peak that uses a strop like this.most are bolts or rope/tat/tape.Derbyshire dales are firmly against any form of bolts placed at the location.i had discussions with the ranger a few years back and was met with a frosty reception.