UKC

Sad to see this classic line is falling appart due to cams being missplaced, glad no one was injured but geeze. it was close!

Flake + cams = bad

In reply to Dave Searle: proof?

In reply to Dave Searle: Oh dear. Do you have any more information?

In reply to Dave Searle:

Is this a new section breaking off, or the bit that broke off about 10 years ago?

Alan

In reply to Alan James - UKC: 10 years? Surely longer?

In reply to Dave Searle: I have no proof alas but there is a big chunk of
rock at the bottom that is proof enough and a hole where it used to be. happened on saturday. Im surprised that im the first to tell people on here.

In reply to Alan James - UKC: Sorry i didn't even know stanage exsisted 10 years ago!
(Im sure it did i just was in school in devon)

In reply to Monk: Off one of the smaller (football-sized) flakes about 10 feet higher up than the big one. I noticed it myself for the first time this weekend. It's certainly fresh damage as the rock scar is bright orange and there's an ominous pile of powder and fragments where this presumably landed. This climb is certainly looking quite battered now. Maybe an indoor wall should make a plastic replica for posterity!

In reply to Monk:

In the picture provided by monk above, would that flake not be safe to put a cam behind? It looks pretty substantial from this angle. Like it goes back quite deep into the rock at a steep angle.

Just wondering. Sorry for thread hijack.

In reply to Dave Searle: the bit that has come off is about a toaster sized piece of the flake just about the second small break above the climbers hands in this photo.

In reply to AmbliKai:

That's the whole point of the thread - cams have exploded two large chunks off this wonderful flake. So not entirely safe, no, although the flake must hold many, many falls, plenty of them onto cams, each year.

It's a real shame, a beautiful line which is starting to look literally dog-eared.

In reply to Dave Searle:

Pretty sure I got good wires and hex's the whole way up this when I lead it, not sure i even placed 1 cam. I don't think i even had any cams when i climbed it, most Hvs's can be reasonably well protected, probably better so, with a good set of wires and a few hex's.

In reply to Martin76:

As legend would have it the lower chunk was the victim of a vicious car-jacking surely?

jk

In reply to Martin76:


My understanding is that the first damge was'nt caused by a cam, but by some idiot using a carjack to retreive a cam?

In reply to Martin76:

I thought the lower one was caused by a jack when someone tried to retrieve a stuck friend?

In reply to Bulls Crack:

I think this is an urban myth.

Alan

In reply to:

Crikey. Never seen a triple whammy like that before. I thought the carjack thing was an urban myth, too, but happy for the 'jacker' to confess all!

I probably overstated it - I guess the most we can say is that on current evidence, we should be regarding that flake with a bit of suspicion when sticking a cam behind it, particularly as there are some nice hex placements etc.

In reply to Alan James - UKC:

Surely its a rural myth rather than urban.

In reply to SiWood:

Have you been to Stanage recently? I felt less hemmed in by folk walking across the concourse at Victoria.

It's the melting pot of modern mountaineering - people from every university in the land.

In reply to Alan James - UKC:

It may be a myth though it was pretty widely reported at the time (I would guess more like 20 years ago). The tip of the flake is/was supposed to reside on a mantelpiece somewhere in the North of England, though as I don't think anyone ever owned up that may also be a myth.


Chris

In reply to Chris Craggs:

I heard that the whole route was created by Whillans tearing the cliff assunder.

In reply to Chris Craggs:

The top of the jug at the crux of Indecent Exposure used to reside on my mantlepiece in Sheffield. Well, you didn't need it anyway!

I offered to glue it back on, if required, but there were no takers. Must have ended up in the bin when I moved.

Mick

In reply to Mick Ward:

Good job you were'nt a Swanage habituee, if you were into gluing holds back on

In reply to JimR:

Quote from a Swanage pioneer, "The flake on Gypsy's fallen down. It's even safer now..."

!!!

Mick

In reply to Dave Searle:

I understand that the piece that came off has been kept for prosperity and resides in Sheffield.

Maybe Mr Redhead is making a collection of broken flakes?

In reply to Martin76:

Clearly you've never been to victoria station

In reply to peteJ23:

That's the funniest but in stone monkey!!

In reply to major stabby: I rest my case

In reply to Bulls Crack:

It's not often I laugh out loud, but this made it happen.

In reply to peteJ23:

Thought he lived in Wales.

In reply to Dave Searle:

Judging by the accent of the bloke who took the fall it won't be residing in sheffield. Newcastle is probably closer the mark.

In reply to homous:

No. It's in Sheffield, trust me.

In reply to Dave Searle:

I think that the whole cams behind flakes ia load of sh*te, especially for the RU.

Think about this for a minute....
I have quoted sizes to make it easier to understand, rather than any other reason.

a 30-40mm wide placement

Use a cam that has a 32mm max size, load it in a fall, how much will it expand? Very little, only the bite into the rock surface.
Use a nut that has a 32mm max size, load it in a fall, what happens, it wedges tighter into the crack.

Now use a cam, that is say 42mm at maximum expansion, if it is in the same placement, how much will it expand? Once again, only into the surface of the rock.

The loading placed upon the gear, does not increase just because it is a cam.
A cam will force into the placement, and then relax, as it becomes unloaded.
A nut will wedge into the crack, and exert the force on the placement until it is removed.

In the case of a loose flake, then cams may be a problem.
a 32mm nut or cam, will wedge the flake open, until 32mm, and then either hold or fail.
a 44m cam will do the same, but just force the placement wider.
Any gear placed behind a loose flake will lever it off, cam or nut.

In the case of the RU, this flake is not being forced to any noticable amount.
However, shock loading of a piece of gear, may cause the bond between the grains of grit to fail.
The force exerted upon the placement is the same, there is no mechanical advantage being gained by a cam, to turn a fall of 3kn in 6kn.

The problem with cams is, the walking action, that erodes the surface of the rock. I noticed this a Brimham recently, where a horizontal break, proably took a 2 1/2, and will now take a 3, just by the rock being worn away, by cams walking.

I hope that makes sense, and will happily be proved wrong, by a reasoned and sensible argument.

I think the car jacking was late 70s..

In reply to major stabby:

Used to fight my way across it (in the wrong direction) every morning. Slight hyperbole, but it is to other stations what Stanage is to most other crags.

In reply to NorthernRock: The direction of the force exerted by the cam is the difference though. Any flake with any 'give' due to being thin/friable will expand with the cam, possibly to failure when it is shock loaded

In reply to Removed User:

Both outward, maybe slightly more vertical in the case of cams, but the loading force remains the same, both would be shock loaded in a fall.

Friable flakes are the problem, and you are aware of those when you place the gear, and yes, in those instances a larger cam than required, may cause more damage.

It is the sweeping generalisation, rather than the specifics, that I feel is misleading.

In reply to Removed User:

But as I said, a nut will also have the same wedging effect, a cam does not impose more load just because it expands. What does a nut do, as it is forced into a constriction? In effect it is expanding outwards to fill all available space (ok a nut doesnt expand, but I hope you get the idea)

In reply to NorthernRock:
I'm buying very little of this.

Cams work by mutliplying the force being pulled down on them on to the walls of the crack this in turn increases friction allowing them to hold falls. I believe it's roughly double the downward force on each edge of the crack. (www.vainokodas.com/climbing/cams.html)

I'd have to do the math on nuts to work out the force against the side walls, but I think the math is much more complicated with a nut as small grains of rock between the nut and the rock and irregularies in the rock and friction as the nut seats better will have a large part to play in exactly how much force is exercted outwards on the crack. Remember for the nut to get more wedged it needs to move against friction which is going to increase the more wedged in to the crack it gets. Personally I'm going with climbing folk lore on this that cams exert more force than nuts when behind flakes etc.

In reply to NorthernRock:
"Both outward, maybe slightly more vertical in the case of cams, but the loading force remains the same, both would be shock loaded in a fall."

the force on the quickdraw attaching to the gear would be the same yes. It's highly unlikely that the force exerted on the rock would be the same. If you are sure it is I'll ask you to do the math and prove it.

In reply to NorthernRock: The fact is that if a flake expands under load from a nut placement, the nut will slipout after the flake opens only a few millimetres (depending on wedge size/angle.

The fact is that a cam will continue to expand, forcing the flake out until it reaches full extension. This I am sure you will agree is generally much wider that the case for the nut.

This extra distance may well be enough to cause the failure of the flake...

In reply to Removed User:

That was the point I was making.
Using a larger cam than required on a friable flake will force it out.

On none friable flakes, of which the RU is one, using a 2 or 21/2 in a placement will not change the force upon the rock, and will not force the flake apart any more with the larger size.

If you body load a cam in a crack, at 75kg, then put a larger cam in, the body load is still 75kg. The larger cam will not force, what is in effect, 2 fixed sides out further.

In reply to NorthernRock:


Unfortunatly that is wrong. The forces placed by a cam on the rock are much much higher than those caused by a nut.

A nut and a cam are loaded by a force X this causes a force R to be exerted by the gear on the rope and a force F by the nut on the rock. In a nut placement this force is caused by the nut trying to move through the rock and thus the force of the nut on the rock is about the same as the force of the rope on the nut so X=R~=F.

For a cam the force R caused by the cam on the rope is the frictional force caused by trying to pull the cam out of the crack (this force is the same as in the nut placement). To generate this force the cam puts a force on the rock perpendicular to the direction of the pull this force is the frictional force divided by the co-efficent of friction and is thus several times as much as the force on the cam so X=R < F

In reply to CurlyStevo:

A nut that is held in place by friction will fail in a fall. The reaction force on a nut is provided by trying to pull the nut through the rock in just the same way that a table resists the force of your dinner plate.

In reply to NorthernRock:

The large pieces of flake that are now missing tend to suggest that assertion may not be entirely correct?

In reply to CurlyStevo:

With a 13 odd degree cam angle, the resolved forces in the outward direction would have to be substantially higher than double - closer to 4x. This force is exerted irrespective of any movement or coefficient of friction.

A nut, on the other hand would exert hardly any outward force if the friction was high.

In reply to Martin76

Indeed sir, your honour is rebound!

In reply to Toreador:

Things break!

In reply to NorthernRock:


I have...and I think you're wrong.

I don't really get your point about a just-big-enough cam (32mm in a 30mm placement) rather than a mid-range placement. Tipped-out placements are dangerous because cams can move, not because the flake is flexible. If the flake is expanding, all bets are off anyway! Flakes on grit tend to be rigid but brittle - they snap iff suffiecient outward force is applied.

Cams create significantly (a multiple) of outward force of passive nuts. The outward (normal) force is the applied downward force divided by the tan of the camming angle. So for a Friend (camming angle 13.75 o), the multiplier is 4 x. The downward force will be affected by the length of rope out and fall distance (fall factor) as well as the type of rope. But the minimum outward force will be fourfold the climber's weight. (In fact it might be eightfold as they are being belayed from below?). If you weigh 75kg, that's 300kg (or 600 possibly). Do this repeatedly and eventually small lines of weakness in the rock will split.

J

In reply to NorthernRock:


Cams by design multiply the applied force and re-direct it outward into the walls of the crack almost normal to the applied load.

Nuts (unless placed in hard, slick taper) don't or do so to a much much lower degree.

jk

In reply to GrahamD:

The actual force generated is determined by the 1/coefficent of friction. The maximum force that can be generated is determined by the cammming angle if the tangent of the camming angle is higher than the coefficent of friction the cam will slip before the reaction force is high enough.

So for the longevity of the route in an original form (as well as its general appearance) a bolt would be preferable?

Carl

In reply to davidwright:

Assuming the friction is high enough for the cam not to slip, though, calculating the outward force is relatively simple and its a straight multiplier on the downward force excerted by the climber.

In reply to carl dawson:

That would be anything but like its original form. But I guess you already knew that.

In reply to davidwright:

David, the force keeping the cam in place is the friction as you state, but the friction force (F) is the normal force (N) times the coefficient of friction (mu).

F = mu * N

now, N is perpendicular to the rock, F is parallel to it. N is constant for a given cam design and a shock load irrespective of the type of rock or its coefficient of friction. The holding force itself is not pulling the flake wide, but the normal force is.

In reply to GrahamD:

... which was this - on sight, with not one runner:

http://tinyurl.com/yj8sozm

Personally I'd rather see a tidy SS staple in it rather than watch Right Unconquerable's beauty further mashed by climbers' removable hardware. But that's just my opinion (being more interested in the aesthetics of the rock rather than the 'ethics' of the ascent); it's not my intended action!

Or perhaps classic routes shown to be vulnerable to such damage should be advised in the future as solo or toprope only... with lead ascents being 'frowned upon'?

Carl

In reply to GrahamD:
"With a 13 odd degree cam angle, the resolved forces in the outward direction would have to be substantially higher than double - closer to 4x. This force is exerted irrespective of any movement or coefficient of friction.
"

Nope suggest you read this just checked the math and it looks right, the outward force on each wall is roughly double the downward force.
http://www.vainokodas.com/climbing/cams.html

In reply to CurlyStevo:

I've just spotted my deliberate mistake ! I forgot that the downward force needs to be resolved on both sides. I take it back; ~2x is right.

In reply to NorthernRock:

The car jack event - if indeed it ever happened - was a few years after I started climbing; so mid 80's

In reply to Dave Searle: Hmmm talk of bolts, nasty. Why not up the grade to take account of the fact that certain parts of the route cannot be protected is RU E2? IIRC well make it E3 or E4 to reflect the added fall potential, most people climbing E2 will be aware of conventions in areas and the odd ones who are not, hey ho, the route will get less traffic in this way and preserve it for future generations or protection developments, or people could just be selfish and climb it to destruction.
Cheers Beds

In reply to J1234: If you are climbing E2 you can put cams in because you're not going to fall on them.

I say resin in a couple of chockstones, then you can thread them in an old skool J.Brown stylee and keep the feeling real man...

In reply to Removed User: Thats a good idea, it would also give some support to the flake, and be asthetically pleasing.

In reply to Removed User:

Good call.

In reply to Removed User:
Rather than gluing the chock stones in couldn't you just leave a basket of suitably sized ones at the bottom of the route so you can place your own? This would also open up the possibility for the hilarious stitch up your second antics of threading the rope behind the chock stone leaving them stuck as they ponder how to remove it

In reply to Dave Searle:

Move it to the plantation bouldering section under 'high balls'.

(I don't care, I've already done it)

In reply to Removed User:


But the chockstone police would remove them (Simon??)

In reply to Gordon Stainforth:


I think the rope was just to slow him down

In reply to Ander:

Seriously, it was simply so that his mates could try to follow him.

In reply to various: As normal, lots of varying opinions about gear and forces, some accurate, some questionable.

It is really simple, a cam with a 13.75 degree camming angle and a wedge with a 13.75 degree taper will exert EXACTLY the same outward forces when loaded. The fact that wedges create massive outward forces is obvious to anyone who has ever used a log splitter. The same applies to hexes placed so they 'cam', they again exert large outward forces,

The only real differences between gear are first the width of the 'wedge' (surface area in contact with the rock) and second the effective length of the 'wedge' (basically how much expansion needs to happen before the gear pulls through). With the exception of micro-wires, nuts and cams have similar contact areas. However, nuts or hex placements will generally need less movement before they fail compared with cams placed at the smaller end of their range.

In 'loose' flakes this means nuts may pull through but leave the flake intact whereas with cams you may end up with both the cam and the whole flake coming away. In these cases, using nuts might be less risky.

However, as has been pointed out, in firmly attached but 'brittle' flakes, there won't be much difference between over-cammed or under-cammed cams, cammed hexes or nuts. The placement will generally either hold or fail catastrophically. In this case the location of the gear (i.e. as close to the base of the flake as possible) is far more important than exactly what gear is used.

In reply to Mark Stevenson:

Not quite as simple as all that, I think. You'd be right only if there were (almost) no friction between the sides and the wedge and the rock.
The same conditions under which it would be equally easy to push a sledge and a cart with wheels on greased axles - a cam has, in effect, wheels.

In reply to Dave Searle:

You can also consider the vector of the forces applied by the gear. In the case of passive pro the vector is close to parallel to the rock and therefore causes less expansion of the crack it is sitting in. For cams the angle of the vector depends on the quality of placement.

If overcammed the vector will be closer to parrallel to the crack walls. This makes it less likely to hold a fall as it cannot generate enough friction to hold itself in the crack.

If undercammed the vector will be closer to perpendicular to the crack wall. This means that it will be exerting a greater expansional force on the crack and therefore will be more likely to tear off friable flacks.

Another idea about how to protect RU; seeing as cams apply forces in proportion to the load placed on them how about proposing a weight limit - only people under 10 stone can place them!

In reply to Mark Stevenson: i would tend to agree with this, whilst reading all the above i couldn`t help but think of how they split large blocks of stone from years ago up to modern day,(and as i use to do when i worked in the slate quarrys years ago),holes were drilled, and then a combination of wedges were hammered home to split the block, this worked because the wedge stayed in the position it was forced into, constantly exerting outward force.
i would presume this is the same if you are constantly falling onto a nut, of which i`m sure happens regularly on RU, where as a friend is only exerting force when fallen onto, then released when force is taken away!
all this said, i can`t see anything changing as far as RU, is concerned, unless maybe........climb per view!!

In reply to Mark Stevenson:

I think you are 100% wrong here. You need to draw the force diagram in both cases.

Of course a wedge works in wood - a) the friction between wood and smooth steel is low and b) you hit it with a bloody big hammer !

In reply to deepsoup:

You're correct. I wrongly assumed that friction was rather insignificant. Had a proper think about it and friction will reduce the outward forces a wedge exerts by a fair amount. If my maths is correct a friction co-efficient of 0.15 would reduce the reaction force for a 13.75 degree wedge compared to a cam from 4.09 to 2.53 times the input force.

So I suppose it is a case that whilst wedges will still exert large outward forces, cams do exert even larger ones.

In reply to GrahamD: See above.

Your point about different surfaces (wood/steel vs gritstone/alloy) is well made.

Thinking about it now, all the times I've had issues with nuts potentially splitting apart flakes have been on slate where there is hardly any friction. In that case the forces will be much higher and closer to that exerted by cams, but I can now see that won't be true for gritstone and other rocks.

In reply to Mark Stevenson:

Top tip for scientists... in cases like bumblebees fly, chalk works and cams are worse than nuts on flakes, the empirical evidence usually has some basis

In reply to Offwidth:
Bumblebees can't fly and anyone who tells you otherwise should be stoned to death with physics textbooks.

In reply to Reach>Talent:

And you should really be stoned with the Oxford English Dictionary: Fly: 'move through the air under control, esp. with wings; travel through the air or through space'.

And guess what? A fly flies too.

In reply to Gordon Stainforth:

Either I'm missing your point or you are unaware that bumblebees can't fly because it's been proven to be impossible by really clever scientists using mathematics.

Although equally clever scientists are now trying to get the bumblebee airborne again by using even cleverer mathematics.

http://knol.google.com/k/claes-johnson/why-bumblebees-can-fly/yvfu3xg7d7wt/...

In reply to EddInaBox:

When the bumble bees realise they can't fly they will hit the flat earth.

In reply to EddInaBox:

Apparently its an urban myth that 'scientists' ever really claimed that bumblebees shouldn't be able to fly.

Discussed in Ben Goldacre's Bad Science and elsewhere

e.g.:

http://www.math.niu.edu/~rusin/known-math/98/bees

In reply to Gordon Stainforth:

Sorry must remember that sarcasm doesn't translate well to forum communication, next time I'll stick in a semi-ironic smiley face. I was poking fun at the obviously stupid assertion that they can't fly.

In reply to Reach>Talent:
I think that too was ironic.

Was the upshot of all this debate that the broken bit on RC was
done with a car jack ages ago (to free a friend?)?

In reply to Jim Nevill:

Well I got it straight away

In reply to Reach>Talent:
But can you now get serious and tells what forces come into play on doing a belly flop at the top of RU?
Rob

In reply to veteye:
Sorry "tell us"

In reply to veteye:
While I am something of a belly flop and whale expert I haven't yet experienced the RU whale so can't comment.

In reply to Reach>Talent:


Yup. The trouble with irony like that is that it is exactly the way many serious scientists speak - indeed the way some scientifically minded people speak on these forums. The very article you quote ends with the extraordinary comment: 'The existing theory is either insufficient, or suggests complex dynamics which has not been verified and would require very intelligent design if actually true.' Why on earth this requirement for 'intelligent design' has to be dragged into it, I just don't know - because if we treat this as a riddle then it leaves much/most of the natural world as baffling in its apparent 'intelligence' as it was to the Rev. William Paley.

So it wasn't entirely clear which angle you were coming from.

In reply to veteye:

Actually, I was surprised how unthrutchy the final mantelshelf of RU was. Probably because I was so scared of it in advance I just did one very powerful/positive mantelshelf move, having got my feet up very high, and was astounded to find that when I belly-flopped forward I could get my right hand right back over the back of the block, i.e. reach a mega-jug. But it all depended on quite good footwork.

In reply to homous:

i belive it was a scouse pirate

In reply to stoned:
Just to clear something up, the bottom corner flake from Right Unconquerable resides in Sheffield in my garden. I found it obviously quite soon after it broke off but didn't see it happen. Soon after,I heard the tale of the car jack but can't comfirm that, although with cams at about £15 - £20 in those days it wouldn't surprise me.

In reply to Dave Searle: Since unless Ive missed something nobosy hasw cleared this up...who has done the route since the latest rock fall last week and has it affected the climbing at all?
Cheers

In reply to Baz47:

Nice to put that one to bed then.

I have the Medusa tree stump in my garden - maybe we should start a museum!

Chris

In reply to Dave Searle:

So are we decided then?

In a deep placement in a solid thick flake, then cams or nuts will make no discernible difference.

Cams on the edge of any flake are bad news.

Chip of a few edges of the flake, and glue them inside, for threading.

Will this make any differnce to my trip to do the LU this week?

In reply to NorthernRock:

Only if your routefinding skills are suspect.

In reply to Dave Searle: I was there it was just unlucky i was taking photos at the time

In reply to Dave Searle: Some geeza did indeed place a cam and fall onto it. I dont know how him or his belayer didn't get hit by the chunck which came off.

What sensible options can we take to preserve this route? Is the lump of rock still at the bottom or is it now on a mantle piece somewhere?