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Descent 310 is out now.
....so prepare to see some of the best writing and photography from the caving world
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Pros and Cons of Different Bolts
- Thread starter hrock
- Start date
Speleokitty
New member
Thats an interesting design that I haven't seen before.
What was the reasoning behind going for this rather than the better known Collinox, Batinox, Ministar, Superstar, Masterfix etc?
What was the reasoning behind going for this rather than the better known Collinox, Batinox, Ministar, Superstar, Masterfix etc?
Glenn
Member
Speleokitty said:
The history of the research behind BCA's Resin Bonded Anchor scheme is well documented so I'll not repeat it here, but basically we wanted an anchor that was instantly recognisable as an anchor that had been installed by a competent installer and was clearly part of the scheme. The original Eco Anchor (the P anchor), manufactured by DMM, was instantly recognisable as part of that scheme, and since DMM no longer manufacture the Eco anchor, we wanted something that looked very much like the Eco, which is why, after extensive testing, we chose the BP anchor.
Speleokitty
New member
I can see some sense in using something that looks different to most others. That doesn't take away the responsability of the rigger to check the anchor but it probably gives them a bit more confidence its been installed properly. We had better just hope everyone doesn't start buying them from Bolt Products.
i have unscrewed the Collinox and reused it elswhere in some circumstances which can be useful but that is probably a reason not to use them in heavily trafficked caves - some people will steal anything.
i have unscrewed the Collinox and reused it elswhere in some circumstances which can be useful but that is probably a reason not to use them in heavily trafficked caves - some people will steal anything.
Glenn
Member
Speleokitty said:
We did not really have that problem with the DMM Eco anchor - although I do know of a few rogue Eco's.
BP anchors installed as part of the BCA scheme are numbered (the image I used of the anchor previously was from the batch supplied for testing). So if the BP anchor is numbered, and it corresponds to the anchor position in the local rigging guide, you should be confident that it's part of the scheme.
Speleokitty
New member
I've got say I'm impressed with the degree of tracability you are introducing with numbered anchors, well done to those involed. I'm not sure I will be joining the queues in the well used sport caves any time soon though. I'll just stick with digging and trips to the little known places.
Another one to collection: http://www.heco-schrauben.de/ceasy/modules/cms/main.php5?cPageId=123
MMS-S Hexagon Head, phosphated tip
stainless steel A4 1.4401 self-colour
Length (mm): 65 to 120
Diameter (mm): 7,5 / 10,0 / 12,0 hole diameter (mm) 6 / 8 / 10
MULTI-MONTI screw anchors made of electrogalvanized steel or 1.4401 grade stainless steel.
MMS-S Hexagon Head, phosphated tip
stainless steel A4 1.4401 self-colour
Length (mm): 65 to 120
Diameter (mm): 7,5 / 10,0 / 12,0 hole diameter (mm) 6 / 8 / 10
MULTI-MONTI screw anchors made of electrogalvanized steel or 1.4401 grade stainless steel.
I wonder - would a suitable blowtorch kept playing on the P head for long enough end up with enough heat absorbed/transmitted to weaken the resin to the point the anchor could be removed/'unscrewed'?
I'd assume that's something someone would have thought of already - if it wouldn't work, it'd be interesting to know why (fumes, rock damage, whatever).
I'd assume that's something someone would have thought of already - if it wouldn't work, it'd be interesting to know why (fumes, rock damage, whatever).
The makers of Bolt Products have thought of it...
http://www.bolt-products.com/SustainableBolting.htm
http://www.bolt-products.com/SustainableBolting.htm
Glenn
Member
potholer said:
The resin is flamable and will give off noxious fumes if heated. But we would only want to remove one if it became dangerously loose, so it's not as if we would ever have lots to replace. In the event that we did need to remove one, I'm quite confident with the knowledge we have accumulated over nearly 30 years would mean we could remove one if we had to.
cap n chris
Well-known member
Our Spanish friends have put together this interesting film which provides food for thought:
Ensayo de Anclajes dentro de una cueva on Vimeo
Ensayo de Anclajes dentro de una cueva on Vimeo
Another tests of Multi-Monti bolts from Italy: http://www.speleocrasc.it/cens12multimonti.htm
On a somewhat related note; when on expedition do people ever use stainless steel through bolts over the normal zinc plated ones or is it not worth it?
The reason I ask is, one particular cave I was helping find new stuff in the bottom of (with lots of stuff still going on) on exped, had the lovely smatter of rusted up spits and occasional through bolts (also rusted), all in the best places to rig from but only a few still actually viable and usually not in the nicest of places. There was certainly some stretching going on rigging it. In such a situation, where I would be expecting people to be going back for a few years, would it be worth some stainless steel through bolts in good positions? Assuming they were well placed in good rock, would they actually stay usable indefinitely? For 10 years? 5 years? Having a quick look at on-line prices, they aren't extravagantly expensive.
The reason I ask is, one particular cave I was helping find new stuff in the bottom of (with lots of stuff still going on) on exped, had the lovely smatter of rusted up spits and occasional through bolts (also rusted), all in the best places to rig from but only a few still actually viable and usually not in the nicest of places. There was certainly some stretching going on rigging it. In such a situation, where I would be expecting people to be going back for a few years, would it be worth some stainless steel through bolts in good positions? Assuming they were well placed in good rock, would they actually stay usable indefinitely? For 10 years? 5 years? Having a quick look at on-line prices, they aren't extravagantly expensive.
I think quite a few people would use stainless throughbolts for expected-permanent rigging and cheaper throughbolts for bolt climbing* or expected-temporary rigging like quick checking out of minor drops not expected to go anywhere.
(*Using stainless for the hang back down from the top, if it turned out to go anywhere.)
As for spits, regular ones seem to last pretty well, at least if in reasonably dry places.
Where I tend to go in the summer, our current target hole gets the main vertical route largely derigged each year (ropes pulled up, metalwork taken out) and the spits seem to be lasting pretty well >10 years later, though a point is made to grease them when derigging.
(*Using stainless for the hang back down from the top, if it turned out to go anywhere.)
As for spits, regular ones seem to last pretty well, at least if in reasonably dry places.
Where I tend to go in the summer, our current target hole gets the main vertical route largely derigged each year (ropes pulled up, metalwork taken out) and the spits seem to be lasting pretty well >10 years later, though a point is made to grease them when derigging.
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