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I'm interested in hearing some more opinions on techniques for cam placements in very shallow cracks. When faced with a vertical crack that isn't deep enough to take the width of the cam head is it preferable to place the cam on just two lobes and align the stem with the direction of a fall or engage all four lobes but have the stem sticking out at 90 degrees to the rock? With solid stems I feel more comfortable with aligning to the direction of a fall but I'd like to hear what people think.
Cheers for any responses.
In reply to Asher Collins:
Don't have an answer to your original question.
But Totem cams are the answer (designed with loading on 2 lobes in mind)
Don't have an answer to your original question.
But Totem cams are the answer (designed with loading on 2 lobes in mind)
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In reply to Asher Collins:
There is no one answer, various factors come into play. For example the more flexible the stem the more lateral load on the cam lobes if all lobes are inserted into the crack, with double axle cams this will be more likely to cause a failure of the lobes than with single axle cams, particularly in the smaller sizes.
There is no one answer, various factors come into play. For example the more flexible the stem the more lateral load on the cam lobes if all lobes are inserted into the crack, with double axle cams this will be more likely to cause a failure of the lobes than with single axle cams, particularly in the smaller sizes.
In reply to Asher Collins:
Tri-cams are pretty good for narrow cracks. A bit fiddlier to place, but you can actually trust they'll support a fall. Or as otherwise mentioned - a Totem.
Tri-cams are pretty good for narrow cracks. A bit fiddlier to place, but you can actually trust they'll support a fall. Or as otherwise mentioned - a Totem.
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In reply to Asher Collins:
When faced with a similar situation in real life I opted for 2 lobes and direction of fall alignment (Black Diamond Camalot IIRC). I then managed to thoroughly test the placement by falling some 20 ft onto it.
It held. Your mileage may vary.
When faced with a similar situation in real life I opted for 2 lobes and direction of fall alignment (Black Diamond Camalot IIRC). I then managed to thoroughly test the placement by falling some 20 ft onto it.
It held. Your mileage may vary.
Post edited at 23:05
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In reply to Asher Collins:
Go with alignment. As soon as you fall, thats how its going to end up. So you should seat it as best you can in that position.
Go with alignment. As soon as you fall, thats how its going to end up. So you should seat it as best you can in that position.
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In reply to deacondeacon:
This was over 10 years ago, so the passage of time has somewhat blurred my memory. I am reasonably sure it was limestone, yorkshire and about E1/E2. I *think* it was The Wally Hunters (E1 5c). However I could be wrong.
This was over 10 years ago, so the passage of time has somewhat blurred my memory. I am reasonably sure it was limestone, yorkshire and about E1/E2. I *think* it was The Wally Hunters (E1 5c). However I could be wrong.
Post edited at 08:49
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In reply to Asher Collins:
It depends on the cams you have. WC zero's you have a good chance with them placed at 90 degs as the lever of the temination crimp does not exist. Anything else and I would move on to something else. Couldn't place a nut? BD C3 have the narrowest head width and make for good marginal placements. 3 cam units like TCU's work well too sometimes...
It depends on the cams you have. WC zero's you have a good chance with them placed at 90 degs as the lever of the temination crimp does not exist. Anything else and I would move on to something else. Couldn't place a nut? BD C3 have the narrowest head width and make for good marginal placements. 3 cam units like TCU's work well too sometimes...
Post edited at 10:10
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In reply to John_Hat:
Its nice to know that psychological protection can work at times.. I've had similar experiences with RP's holding a fall I never expected them to stop. When I first got my Aliens people told me they would never hold falls (they have quite a few times). Equally I've seen, and heard of several other occasions, when the perfect cam slot on Flying Buttress Direct on Stanage spat out its cam (one reason it will always be solid E1 in my view as an onsight).
Its nice to know that psychological protection can work at times.. I've had similar experiences with RP's holding a fall I never expected them to stop. When I first got my Aliens people told me they would never hold falls (they have quite a few times). Equally I've seen, and heard of several other occasions, when the perfect cam slot on Flying Buttress Direct on Stanage spat out its cam (one reason it will always be solid E1 in my view as an onsight).
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In reply to Offwidth:
The horizontal one on the lip? I put two in, I didn't fancy the pendulum into the slab!
The horizontal one on the lip? I put two in, I didn't fancy the pendulum into the slab!
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In reply to Asher Collins:
I think it's worth mentioning that the directions in which runners will be loaded in a fall aren't consistent, and can be difficult reliably to predict: the bottom runner will usually be pulled outwards, and the top runner may also be subjected to some degree of outward force, depending on the distance/nature of the fall. Interim runners won't be loaded at all unless the top one fails, in which case the loading is more likely to be downwards on the next one down; or the bottom one fails, when the loading on the next one up is likely to be pretty much directly outwards.
Where possible I put my first cam aligned outwards (even if it's not the first piece, because a lower nut can easily be pulled/levered out). Higher cams I align about 30% outwards (again, where possible - the security of the placement is also a factor, of course).
> and align the stem with the direction of a fall or engage all four lobes but have the stem sticking out at 90 degrees to the rock? With solid stems I feel more comfortable with aligning to the direction of a fall
I think it's worth mentioning that the directions in which runners will be loaded in a fall aren't consistent, and can be difficult reliably to predict: the bottom runner will usually be pulled outwards, and the top runner may also be subjected to some degree of outward force, depending on the distance/nature of the fall. Interim runners won't be loaded at all unless the top one fails, in which case the loading is more likely to be downwards on the next one down; or the bottom one fails, when the loading on the next one up is likely to be pretty much directly outwards.
Where possible I put my first cam aligned outwards (even if it's not the first piece, because a lower nut can easily be pulled/levered out). Higher cams I align about 30% outwards (again, where possible - the security of the placement is also a factor, of course).
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In reply to John_Hat:
Sounds like a substantial dry cleaning bill.
Thanks for advice. Sounds like two lobes is the way to go (no pun intended).
Sounds like a substantial dry cleaning bill.
Thanks for advice. Sounds like two lobes is the way to go (no pun intended).
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In reply to Asher Collins:
Sorry, but I regard beardy mikes and bpmclimbs understanding of the physics involved to be nearer reality.
Even Totem suggest that two cams are for aid only on their units.
Two cams apply opposing forces just like 4 or 3. But... only two cams are not opposing on the axle and resulting forces, unless you are very lucky or canny, will exert a twisting motion on the head and the unit will usually fail in a fall.
> Sounds like a substantial dry cleaning bill.
> Thanks for advice. Sounds like two lobes is the way to go (no pun intended).
Sorry, but I regard beardy mikes and bpmclimbs understanding of the physics involved to be nearer reality.
Even Totem suggest that two cams are for aid only on their units.
Two cams apply opposing forces just like 4 or 3. But... only two cams are not opposing on the axle and resulting forces, unless you are very lucky or canny, will exert a twisting motion on the head and the unit will usually fail in a fall.
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In reply to Asher Collins:
Not necessarily, depends on the route/placement/etc. In my case I had limited options due to what I was carrying and what was in front of me at the time....
Obviously with an infinite rack, and a different route, a different option might work better.
For what it's worth, I have also fallen on a cam with the stem pointing 90 degrees from the rock. The cam was nicely in though and held fine, though the stem was twisted and knackered.
I would say the answer to your question depends on how much of the cam head you can get into the crack, which will clearly vary by cam and placement.
My anecdote shows that two-lobes-only *can* hold, but it's not a plcement I would choose if any other option was available. Unfortunately at the time, it wasn't.
> Sounds like a substantial dry cleaning bill.
> Thanks for advice. Sounds like two lobes is the way to go (no pun intended).
Not necessarily, depends on the route/placement/etc. In my case I had limited options due to what I was carrying and what was in front of me at the time....
Obviously with an infinite rack, and a different route, a different option might work better.
For what it's worth, I have also fallen on a cam with the stem pointing 90 degrees from the rock. The cam was nicely in though and held fine, though the stem was twisted and knackered.
I would say the answer to your question depends on how much of the cam head you can get into the crack, which will clearly vary by cam and placement.
My anecdote shows that two-lobes-only *can* hold, but it's not a plcement I would choose if any other option was available. Unfortunately at the time, it wasn't.
Post edited at 15:02
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In reply to Rick Graham:
Thanks for your reply.
I'm aware of the twist from a two lobe placement but thanks for mentioning it. There's a good couple of pages on two lobe placements here...
https://www.google.co.uk/url?sa=t&source=web&rct=j&url=https://...
Just to clarify this isn't a a question about a route I'm planning. I climbed past a placement like this last week and I'm just interested in what people would do had there been nothing else about.
Thanks for your reply.
I'm aware of the twist from a two lobe placement but thanks for mentioning it. There's a good couple of pages on two lobe placements here...
https://www.google.co.uk/url?sa=t&source=web&rct=j&url=https://...
Just to clarify this isn't a a question about a route I'm planning. I climbed past a placement like this last week and I'm just interested in what people would do had there been nothing else about.
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In reply to Asher Collins:
Thats a very useful explanation of the issues involve, thanks, not sure if seen it before.
Always thought Totem missed a trick here in potentially rounding off or faceting the cam lobe faces so there is a more stable opposing face set up.
I bet the hardcore US aid climbers, who have multiple sets of cams, have some modified ones
> Thanks for your reply.
> I'm aware of the twist from a two lobe placement but thanks for mentioning it. There's a good couple of pages on two lobe placements here...
> Just to clarify this isn't a a question about a route I'm planning. I climbed past a placement like this last week and I'm just interested in what people would do had there been nothing else about.
Thats a very useful explanation of the issues involve, thanks, not sure if seen it before.
Always thought Totem missed a trick here in potentially rounding off or faceting the cam lobe faces so there is a more stable opposing face set up.
I bet the hardcore US aid climbers, who have multiple sets of cams, have some modified ones
In reply to Rick Graham:
How would that work? Any chance of a picture - the two cam lobes are still in the same position. Is it to limit the rotation as per the illustration in that totem link?
How would that work? Any chance of a picture - the two cam lobes are still in the same position. Is it to limit the rotation as per the illustration in that totem link?
In reply to Asher Collins:
As mentioned above, Totam cams can be placed with just 2 lobes, but you need to clip just that side, through the black loope. I have a set & think they're great.
http://www.peter-hoang.com/totem-cam-review/
As mentioned above, Totam cams can be placed with just 2 lobes, but you need to clip just that side, through the black loope. I have a set & think they're great.
http://www.peter-hoang.com/totem-cam-review/
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In reply to Rick Graham:
At one time there were cams made by a company called splitter who did a 2 cam unit in which the cam lobes were directly opposed. They had limited range but would go in very very shallow cracks in the correct orientation and were designed for el cap peg scars etc and marginal aid placements. IMO I wouldn't be trusting totems on 2 lobes to take a fall. If I was absolutely desperate then maybe but I wouldn't be a happy man.
Heres some pics of the splitters... consigned to the ether where cams go to die...
http://www.angelfire.com/trek/coolclimbinggear/protection.html
At one time there were cams made by a company called splitter who did a 2 cam unit in which the cam lobes were directly opposed. They had limited range but would go in very very shallow cracks in the correct orientation and were designed for el cap peg scars etc and marginal aid placements. IMO I wouldn't be trusting totems on 2 lobes to take a fall. If I was absolutely desperate then maybe but I wouldn't be a happy man.
Heres some pics of the splitters... consigned to the ether where cams go to die...
http://www.angelfire.com/trek/coolclimbinggear/protection.html
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In reply to beardy mike:
Good old Mike, always got the info : -)
Have you ever had a night out in the pub with Ian Parsons ? He lives in your neck of the woods.
You two would be climbing quiz champions.
Good old Mike, always got the info : -)
Have you ever had a night out in the pub with Ian Parsons ? He lives in your neck of the woods.
You two would be climbing quiz champions.
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In reply to wbo:
Chamfer the opposing edges so the two parallel faces have directly opposite force vectors.
Possibly the best that can be accomplished in a shallow parallel crack.
Any rugosities or other taper and a Tricam or sideways Wallnut would be my likely hot option.
> How would that work? Any chance of a picture - the two cam lobes are still in the same position.
Chamfer the opposing edges so the two parallel faces have directly opposite force vectors.
Possibly the best that can be accomplished in a shallow parallel crack.
Any rugosities or other taper and a Tricam or sideways Wallnut would be my likely hot option.
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In reply to beardy mike:
The single cam CMI Kirk's Kamm (1976) & RoKJoX (1987) were a similar idea.
Tony
The single cam CMI Kirk's Kamm (1976) & RoKJoX (1987) were a similar idea.
Tony
In reply to Rick Graham:
He was the chap who did Faces with Allison Hargreaves and Jim Ballard right?
He was the chap who did Faces with Allison Hargreaves and Jim Ballard right?
In reply to Rick: thanks. How small were the smallest amigo's . They were a single cam either side of an axle? I never used those
In reply to wbo:
http://www.needlesports.com/content/nuts-story-clockwork-friends.aspx
Really a slider type device. I think they were only popular on Masters Edge.
> thanks. How small were the smallest amigo's . They were a single cam either side of an axle? I never used those
http://www.needlesports.com/content/nuts-story-clockwork-friends.aspx
Really a slider type device. I think they were only popular on Masters Edge.
In reply to tk421:
We'll that just isn't true, since he is talking about rock climbing falls.
Totems are rated to bodyweight only on 2 lobes.
> But Totem cams are the answer (designed with loading on 2 lobes in mind)
We'll that just isn't true, since he is talking about rock climbing falls.
Totems are rated to bodyweight only on 2 lobes.
In reply to ipfreely:
"The cams take some getting used to, as the stems are more flexible than most on the market. The cams will be more stable, but more difficult to place - not that it's hard or anything.
For durability, I found that the cam lobes were dented in some areas(though not severely so) after a couple uses. I suspect the lobe design exerts larger amounts of force to smaller areas, causing the damage, or a softer alloy was used on the lobes for biting power.
After slings, wires are usually the first to go on my cams. I was happy to see that the Totem wires are nice and burly, with many of them covered up completely with plastic or springs."
These are the conclusions drawn from that review and sorry that just makes me cringe. The alloy is not softer - its 7075-t6 and is stated as such somewhere on their website. Bar 7068-t6 that's pretty much the hardest commonly available aluminium alloy.
More force? Just when seated? If he's fallen on them, most cams would see denting on the lobe surface. If he's used to using cams with anodised lobes, then they are harder to dent because the anodisation causes slight surface hardening.
Burly wires? Well they are galvanised wires. Plastic over them will retain water if they get wet which means corrosion will over time happen beneath the plastics. And wires generally do not fray in the middle, they fray where they have been crimped beneath a ferrule causing a stress riser in the wire.
None of this means you shouldn't buy totems, it just makes me think the reviewer doesn't know his stuff.
Edit: I just read the rest of the review, and it's as bad. Lots of anecdotal evidence with no comparison. Statements like more force exerted by the cam producing a safer placement - not behind a flake when you have a far higher chance of breaking the flake as the force really is MUCH higher. And Asymmetrical cam lobes? What the hell does that even mean? The cam lobe shape is no different on its contact surface to any other cam. Maybe he means the eccentrically loaded cams?
"The cams take some getting used to, as the stems are more flexible than most on the market. The cams will be more stable, but more difficult to place - not that it's hard or anything.
For durability, I found that the cam lobes were dented in some areas(though not severely so) after a couple uses. I suspect the lobe design exerts larger amounts of force to smaller areas, causing the damage, or a softer alloy was used on the lobes for biting power.
After slings, wires are usually the first to go on my cams. I was happy to see that the Totem wires are nice and burly, with many of them covered up completely with plastic or springs."
These are the conclusions drawn from that review and sorry that just makes me cringe. The alloy is not softer - its 7075-t6 and is stated as such somewhere on their website. Bar 7068-t6 that's pretty much the hardest commonly available aluminium alloy.
More force? Just when seated? If he's fallen on them, most cams would see denting on the lobe surface. If he's used to using cams with anodised lobes, then they are harder to dent because the anodisation causes slight surface hardening.
Burly wires? Well they are galvanised wires. Plastic over them will retain water if they get wet which means corrosion will over time happen beneath the plastics. And wires generally do not fray in the middle, they fray where they have been crimped beneath a ferrule causing a stress riser in the wire.
None of this means you shouldn't buy totems, it just makes me think the reviewer doesn't know his stuff.
Edit: I just read the rest of the review, and it's as bad. Lots of anecdotal evidence with no comparison. Statements like more force exerted by the cam producing a safer placement - not behind a flake when you have a far higher chance of breaking the flake as the force really is MUCH higher. And Asymmetrical cam lobes? What the hell does that even mean? The cam lobe shape is no different on its contact surface to any other cam. Maybe he means the eccentrically loaded cams?
Post edited at 08:53
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In reply to beardy mike:
The link i posted was purely for the 2nd picture showing the cam placed with only 2 lobes in the crack, i didn't read any attached review.
The link i posted was purely for the 2nd picture showing the cam placed with only 2 lobes in the crack, i didn't read any attached review.
In reply to ipfreely:
Totally - not saying you were doing anything else, just casting doubt upon the reviewers knowledge incase people read what he wrote as fact...
Totally - not saying you were doing anything else, just casting doubt upon the reviewers knowledge incase people read what he wrote as fact...
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