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tradmanclimbs


Apr 24, 2012, 2:16 PM
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Re: [healyje] link cam broken when fallen on [In reply to]
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Have not read a glossy mag in years . When I did read the link cam adds years ago when they first came out they were very clearly marketed as a do anything and everything cam. After useing them and hearing about many failures I feel that when used by the average climber they are a time bomb. They should have a large disclaimer on them. UNLESS YOU ARE A TOTAL GEEK WHO CAN AND WILL CALCULATE EVERY POSSIBLE MICRO ANGLE OF PULL FOR EACH AND EVERY PLACEMENT DO NOT USE THESE CAMS!

YMMV


patto


Apr 24, 2012, 3:36 PM
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Re: [tradmanclimbs] link cam broken when fallen on [In reply to]
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tradmanclimbs wrote:
UNLESS YOU ARE A TOTAL GEEK WHO CAN AND WILL CALCULATE EVERY POSSIBLE MICRO ANGLE OF PULL FOR EACH AND EVERY PLACEMENT DO NOT USE THESE CAMS!

To one degree or another most trad climbers are "geeks".

It takes a certain amount of trust in ones own abilities to read, understand and control the risks to trad climb. "Geeks" that understand the mechanics and forces involved in trad climbing can trust themselves to control them.

I have seen many good climbers step away from trad climbing because they are smart enough to realise that they don't have the appropriate skills to trad climb.

I have encountered only very few decent trad climbers who don't have a degree of geekiness. Even then their ability to assess new gear, gear placements and scenarios may be inferior if they shun the geeky analysis.


tradmanclimbs


Apr 24, 2012, 6:45 PM
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Re: [patto] link cam broken when fallen on [In reply to]
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As a confirmed geek tradclimber I am raiseing the bar on the link cam to only be used by TOTAL geeks. Us reguler geeks prefer gear that will not self destruct that easily. YMMV


climbingaggie03


Apr 24, 2012, 9:38 PM
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Re: [tradmanclimbs] link cam broken when fallen on [In reply to]
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Just to weigh in, I placed my #2 link this past week while climbing in Moab. I've had my link cam for a long time. I got it not long after they came out, and definitely before the first failure (which I think was on left ski track in Josh)

I bought mine on the marketing that it was a great piece for panic situations, or flares. I'd say that experience has shown that this is not necessarily the case. I still like my Link cam though. I'll admit that I've never fallen on it, however I have weighted it in TR anchors, and in aiding.

The extended range is the major benefit of the link cams, even if the drawbacks are that you have to be very careful with your placements. I love mine if I need an extra mid range piece, but don't want to cary the green, red and yellow camalots. I love it for crack jumaring. I love it for an anchor piece. I placed it this week because I was pumped in a crux and I needed to get the right piece in fast. I love it if I'm heading up to set up a TR anchor and I'm not exactly sure what size gear I'll need.

Do they have limitations? absolutely. I didn't know the limitations (neither did OP I believe) when I first bought it, but in my opinion, it's still a useful piece, even if I have to be more careful when I place it.


djayr


Apr 24, 2012, 9:52 PM
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Re: [climbingaggie03] link cam broken when fallen on [In reply to]
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I love the "these are not normal cams" discussion in this group. I have used links and haven't had issues but I never fell on one and don't; intend too--i think of them as ice screws. i agree with the posts that makes fun of the fact that climbers are/are not geeks. When i climb i'm also not thinking about angles and ALL the possible fall angles. Plus the Omega site says this:

"Be sure to anticipate direction of load, should you fall or weight the cam. This is particularly important with Link Cams, due to their unique construction. Since they are built using trisected cam lobes, Link Cams can become damaged—and the placement may fail—if a load is placed that makes the cam “shift” when a climber falls onto it.... Although Link Cams’ flexible stems can help “correct” a less-than-ideal placement, it is still important that the initial placement be made in proper alignment with anticipated load."

Its basically saying that unless you place them "perfectly" they could fail. Erroneous! why use something so dubious in unpredictable environment? I've fallen on many cams and mangled they held. I won't be trusting a link "cam" Its a great piece of shitty gear for false sense of security and i use it for that when i need a good dose of encouragement. But i know i'm getting bullshit.


tradmanclimbs


Apr 25, 2012, 3:12 AM
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Re: [jt512] link cam broken when fallen on [In reply to]
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The real idiot is the guy who uses Link cams as TR anchors. Gear can shift when you tr on it and most often you can not see it untill you get to the top and inspect the anchor. BTW when Top roping on gear you should inspect the anchor every lap. Can not imagin being so lazy that I would use a link cam for a TR anchor simply because I did not feel like carrying the extra weight of a selection of more robust and actually bomber gear.


patto


Apr 25, 2012, 3:47 AM
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Re: [tradmanclimbs] link cam broken when fallen on [In reply to]
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tradmanclimbs wrote:
BTW when Top roping on gear you should inspect the anchor every lap.

You have got to be kidding me. Crazy How much of a trad man are you?


A well set up top rope can be used all day without needing inspection. Trad or bolts it makes no difference to me.


csproul


Apr 25, 2012, 7:37 AM
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Re: [patto] link cam broken when fallen on [In reply to]
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patto wrote:
tradmanclimbs wrote:
BTW when Top roping on gear you should inspect the anchor every lap.

You have got to be kidding me. Crazy How much of a trad man are you?


A well set up top rope can be used all day without needing inspection. Trad or bolts it makes no difference to me.
I see...so you don't bother to check your TR rig every once in a while? A well set up TR should not need to be messed with during the course of a day, but that doesn't mean that I'm not going to periodically take a look at it when I get to the top. Maybe not every lap, but at least periodically, and I certainly wouldn't deride anyone else who wanted to do so. This is especially true at some of our more crowded destinations where it is not unheard of to have clueless people up top messing around with things.


patto


Apr 25, 2012, 8:13 AM
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Re: [csproul] link cam broken when fallen on [In reply to]
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csproul wrote:
Maybe not every lap, but at least periodically, and I certainly wouldn't deride anyone else who wanted to do so.
Sure.

But I wasn't deriding anybody who wanted to check their top rope every lap. I was deriding somebody who was other SHOULD check their top rope every lap.


I set up 8 top ropes for a large group last weekend. I checked them all before we started. They were used for 5 hours before they were taken down. Why would one need to check a top rope set up more than daily?


billcoe_


Apr 25, 2012, 9:36 AM
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Re: [patto] link cam broken when fallen on [In reply to]
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To the OP, thanks for the report. As you say, not everyone knows this. I just came back from a climbing trip where I wound up explaining why I left my Link Cams at home for the trip to a younger and newer climber. He had a very hard time grasping this issue as he was lusting after them so badly. To reiterate the finer points, just go re-real all Healyjh's posts above as that was my discourse to the lad in a nutshell. You need to understand the limitations of the things. Once ya do, there's not a point in accepting those significant and serious limitations unless the route specifically will gain you something by having them, and those routes, which are out there it's true, are few and far between. So I'll leave the Links at home most of the time. I'd recommend others do likewise.

The Link Cams are a specialty piece that so underperforms Metolius, Totem cams and others, that for me, the risk is just not worth bothering racking the things at all unless I have that specific need. Like US Navy says above about crack jugging. I'm glad I own some, and they are an otherwise fine and amazing piece for those specific uses. Otherwise, I do NOT carry them at all. Anyone who climbs with me knows to do the same.


climbingaggie03


Apr 25, 2012, 9:55 AM
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Re: [tradmanclimbs] link cam broken when fallen on [In reply to]
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tradmanclimbs wrote:
The real idiot is the guy who uses Link cams as TR anchors. Gear can shift when you tr on it and most often you can not see it untill you get to the top and inspect the anchor. BTW when Top roping on gear you should inspect the anchor every lap. Can not imagin being so lazy that I would use a link cam for a TR anchor simply because I did not feel like carrying the extra weight of a selection of more robust and actually bomber gear.


I do keep an eye on it every now and then, and I'd say it's not about lazyness, but more about safety. I haven't spent much time in VT but frequently where I climb, the scramble around for a TR anchor is not a class 1 hike, and the less I have to carry, the safer I feel.

My TR anchors are ALWAYS atleast 3 pieces(if I'm using gear), and I'm always concious of the direction of pull on the anchor.

You can't keep an eye on a cam when you're leading, after you clip it and keep climbing so I'd say that using it in a TR set up when there are 2 back ups is safer than it being the only thing between you and the ground/ledge.


healyje


Apr 25, 2012, 11:50 AM
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Re: [billcoe_] link cam broken when fallen on [In reply to]
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billcoe_ wrote:
You need to understand the limitations of the things. Once ya do, there's not a point in accepting those significant and serious limitations unless the route specifically will gain you something by having them, and those routes, which are out there it's true, are few and far between.

Exactly, well said.


tradmanclimbs


Apr 25, 2012, 3:56 PM
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Re: [healyje] link cam broken when fallen on [In reply to]
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patto. you didn't check em all day?

that is why they call it camp kill a kidCool


patto


Apr 25, 2012, 4:02 PM
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Re: [tradmanclimbs] link cam broken when fallen on [In reply to]
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tradmanclimbs wrote:
patto. you didn't check em all day?

that is why they call it camp kill a kidCool

No kids involved.

You still haven't explained why it is necessary to constantly check trad gear. Furthermore the bigger risk factor in repeatedly used TR is not over trad gear it is concerning rubbing and wear. This naturally can occur whether it is trad or bolted.

I am happy to leave a redundant top rope set up running all day when built using 10mm+ rope with multiple redundancy and no rub points.


tradmanclimbs


Apr 25, 2012, 5:00 PM
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Re: [patto] link cam broken when fallen on [In reply to]
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Shit happens, things can shift. eyes on after every lap is a good way to grow old. I do the same with bolts but there are fewer chances of a screwup with bolts or slung trees than with trad gear. either way eyes on is a no brainer. Granted I don't get to the top of the cliff to check when putting up and working a new route solo. Does not mean that I don't sweat bullets on that last jug to the top @ the end of the day. It ain't paranoia if they really are out to get youWink When I do my free solo workout laps I eyeball the other folks anchors on my way accross the top of the cliff. It's a habbit.. I have caught a few screw ups over the years that way.. Rope jumped out of one biner, gate unscrewed and wedged against the other biner with both gates open. that sort of thing..

Running a group all day without checking the top anchors. bad juju... Crazy


patto


Apr 25, 2012, 5:25 PM
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Re: [tradmanclimbs] link cam broken when fallen on [In reply to]
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tradmanclimbs wrote:
Shit happens, things can shift. eyes on after every lap is a good way to grow old. I do the same with bolts but there are fewer chances of a screwup with bolts or slung trees than with trad gear. either way eyes on is a no brainer. Granted I don't get to the top of the cliff to check when putting up and working a new route solo. Does not mean that I don't sweat bullets on that last jug to the top @ the end of the day. It ain't paranoia if they really are out to get youWink When I do my free solo workout laps I eyeball the other folks anchors on my way accross the top of the cliff. It's a habbit.. I have caught a few screw ups over the years that way.. Rope jumped out of one biner, gate unscrewed and wedged against the other biner with both gates open. that sort of thing..

Running a group all day without checking the top anchors. bad juju... Crazy

You haven't said anything there. Bad juju is not an explanation. Ropes don't just jump out of biners. Biners don't just magically become unscrewed.

Set things up properly and things will stay good. Set them up badly and things may turn bad before you check it again.


tradmanclimbs


Apr 25, 2012, 6:06 PM
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Re: [patto] link cam broken when fallen on [In reply to]
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Whatever. you do your thing. I do not guide large groups. Don't believe in that kind of climbing. the only time I ever TR is when I am workring a new route decideing if it is worth bolting. Used to only put routs up GU but getting a bit wiser in my old age... When I do guide I take that responsibility seriously and if it is a TR situation I get eyes on that anchor periodicly. YMMV


USnavy


Apr 26, 2012, 10:48 PM
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Re: [healyje] link cam broken when fallen on [In reply to]
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healyje wrote:
USnavy wrote:
No it's not impossible, not even close. The guy that fell on the cam took a factor one fall on it. What likely happened is the cam ran out of range and it umbrellaed. That's is not only very possible, it is very likely.

Hey, did you even bother to read what I wrote?

healyje wrote:
The only way it can happen is to fall on a piece that isn't placed securely, or is placed securely in less than idea rock, and said cam drags to a wider section of the crack where the cam then inverts. That's why you need to pay exceptional attention to detail when placing all forms of small pro.

Cams don't "ran out of range", unless they were placed badly
Except that's my entire point, in the case of small cams, a "bad placement" is pretty common. Its hard to inspect micro cams and determine how much expansion range is remaining on the back lobes. You can get away with placing a #2 Camalot at 30% cammed, but try that on a 0 TCU and forget about it, it's probably not going to hold any legit lead fall.

Watch this video at the 1:00 mark: http://www.youtube.com/watch?v=xparZFsBS40

Note that those cams are being pulled in a 1" thick steel jig, probably made out of T3 steel or something similar. As you might have noticed, the jig does not move or compress at all. So the cam movement you saw in that video is a function of the cam bending and compressing. The same thing happens when you fall on a cam in the real world, just to a lesser extent because you are not loading it to 10 kN like in the video.

However, that issue is the less important of the two. The other issue is the compression of the rock. If the rock compresses even just 1/8", that could be sufficient to cause a microcam to rip. When you are talking about softer material like sandstone, forget about it, it is very easy to get material like that to compress when the force on the rock under the lobes is easily in the many thousands of PSI.

The entire point I am trying to make is that the difference between a fully retracted cam and a cam that is nearly tipped out is very subtle when talking about microcams. Its very easy, even for experienced trad climbers, to place a microcam with the outside lobes 75% camed, but fail to realize there is a very shallow flair to the crack and the inside lobes are only 25% camed. Microcams have no expansion range below 50%. If you dont get them in a position where all the lobes are fully retracted, you basically have a piece of passive pro at that point. The remaining expansion range could easily be in the 1/32" to 1/16" range which is nothing, just the compression and torsion of the cam on a fall can expend that range.


(This post was edited by USnavy on Apr 27, 2012, 3:55 AM)


healyje


Apr 27, 2012, 12:03 AM
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USnavy wrote:
Note that those cams are being pulled in a 1" thick steel jig, probably made out of T3 steel or something similar. As you might have noticed, the jig does not move or compress at all. So the cam movement you saw in that video is a function of the cam material compressing and bending. The same thing happens when you fall on a cam in the real world, just to a lesser extent because you are not loading it to 10 kN like in the video.

Good video, but look closely and you'll see that is not cam lobe material compression, but rather axle deformation of the kind cracklover was speaking of. Despite the axle deformation the cams are working as they were designed right up until the stem breaks.

But we certainly agree micro cams - and all small pro - can easily be placed badly if you aren't paying attention to very minute details when placing them. And once badly placed it's worthless and not worth having stopped to place it.

You have to get way down to the millimeter level on inspection and placement with small pro - as USNavy is hinting at, rock quality can change quite drastically over the course of inches or less in some stone.


tradmanclimbs


Apr 27, 2012, 2:29 AM
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Margin for error. all micro gear regardless of type or brand has pretty much zero margin for error. placed perfectly in good quality rock and it can have amazeing results. Mess it up just a little bit and it's what Joe said... a waste of time..


USnavy


Apr 27, 2012, 3:54 AM
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Re: [healyje] link cam broken when fallen on [In reply to]
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healyje wrote:
USnavy wrote:
Note that those cams are being pulled in a 1" thick steel jig, probably made out of T3 steel or something similar. As you might have noticed, the jig does not move or compress at all. So the cam movement you saw in that video is a function of the cam material compressing and bending. The same thing happens when you fall on a cam in the real world, just to a lesser extent because you are not loading it to 10 kN like in the video.

Good video, but look closely and you'll see that is not cam lobe material compression, but rather axle deformation of the kind cracklover was speaking of. Despite the axle deformation the cams are working as they were designed right up until the stem breaks.

But we certainly agree micro cams - and all small pro - can easily be placed badly if you aren't paying attention to very minute details when placing them. And once badly placed it's worthless and not worth having stopped to place it.

You have to get way down to the millimeter level on inspection and placement with small pro - as USNavy is hinting at, rock quality can change quite drastically over the course of inches or less in some stone.
You're correct, I meant to say axle deformation, although I imagine the lobes probably compressed to some small extent. I know for fact that the lobes on an Alien will compress if you take a legit fall on them. I flattened out the lobes on one of my blue Aliens awhile back taking a small factor .75 fall on it. Interestingly enough it held, but the cam was at my foot, I dident go very far and the cam was in steel hard rock with nearly 90% lobe retraction.


jt512


Apr 27, 2012, 9:36 AM
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USnavy wrote:
healyje wrote:
USnavy wrote:
Note that those cams are being pulled in a 1" thick steel jig, probably made out of T3 steel or something similar. As you might have noticed, the jig does not move or compress at all. So the cam movement you saw in that video is a function of the cam material compressing and bending. The same thing happens when you fall on a cam in the real world, just to a lesser extent because you are not loading it to 10 kN like in the video.

Good video, but look closely and you'll see that is not cam lobe material compression, but rather axle deformation of the kind cracklover was speaking of. Despite the axle deformation the cams are working as they were designed right up until the stem breaks.

But we certainly agree micro cams - and all small pro - can easily be placed badly if you aren't paying attention to very minute details when placing them. And once badly placed it's worthless and not worth having stopped to place it.

You have to get way down to the millimeter level on inspection and placement with small pro - as USNavy is hinting at, rock quality can change quite drastically over the course of inches or less in some stone.
You're correct, I meant to say axle deformation, although I imagine the lobes probably compressed to some small extent. I know for fact that the lobes on an Alien will compress if you take a legit fall on them. I flattened out the lobes on one of my blue Aliens awhile back taking a small factor .75 fall on it. Interestingly enough it held, but the cam was at my foot, I dident go very far and the cam was in steel hard rock with nearly 90% lobe retraction.

You think a .75-factor fall is "small"? On a blue Alien? I'm starting to understand why you've already experienced four cam failures in such a short climbing career.

Jay


healyje


Apr 27, 2012, 10:29 AM
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Aliens were / are made of 6061 aluminum and mush out fast accordingly. Metolius are 7075 and harder which gives them marginally less bite, but deform less as I believe are BD and WC cams. So yes, the Aliens definitely do tend to "flatten" more than other cams.


USnavy


Apr 27, 2012, 5:25 PM
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jt512 wrote:
USnavy wrote:
healyje wrote:
USnavy wrote:
Note that those cams are being pulled in a 1" thick steel jig, probably made out of T3 steel or something similar. As you might have noticed, the jig does not move or compress at all. So the cam movement you saw in that video is a function of the cam material compressing and bending. The same thing happens when you fall on a cam in the real world, just to a lesser extent because you are not loading it to 10 kN like in the video.

Good video, but look closely and you'll see that is not cam lobe material compression, but rather axle deformation of the kind cracklover was speaking of. Despite the axle deformation the cams are working as they were designed right up until the stem breaks.

But we certainly agree micro cams - and all small pro - can easily be placed badly if you aren't paying attention to very minute details when placing them. And once badly placed it's worthless and not worth having stopped to place it.

You have to get way down to the millimeter level on inspection and placement with small pro - as USNavy is hinting at, rock quality can change quite drastically over the course of inches or less in some stone.
You're correct, I meant to say axle deformation, although I imagine the lobes probably compressed to some small extent. I know for fact that the lobes on an Alien will compress if you take a legit fall on them. I flattened out the lobes on one of my blue Aliens awhile back taking a small factor .75 fall on it. Interestingly enough it held, but the cam was at my foot, I dident go very far and the cam was in steel hard rock with nearly 90% lobe retraction.

You think a .75-factor fall is "small"? On a blue Alien? I'm starting to understand why you've already experienced four cam failures in such a short climbing career.

Jay
The fall distance was small; we are talking about a total fall distance of maybe five feet. Anyway, that is the only time I have taken a hard[er] fall on a cam, the other cams incidents I referenced were all below factor .25. And I haven’t experienced four cam failures, I have experienced more than that, just four involved the cam sliding down the rock in seemingly good placements. However, I have had only one cam pull on the mainland and I climb a lot more trad in the continental USA than I do in Hawaii. As I said before, climbing trad here is tricky. The majority of the cracks are small and require small gear, the cracks are parallel so they require cams and they do not easily accept nuts, and the rock is made out of lava which is not exactly the most optimal stuff to climb trad on. The problem with our basalt, aside from being too smooth in parts, is that the outside layer of the rock cooled faster than the inside when it formed which results in two separate layers. The outer layer is basically just a bunch of cornflakes glued together for 1/4". When you fall on a cam that is placed on this outer layer, the cornflakes break off and cam can pull.

At first, some ask why we have bolted cracks:





Well, aside from the fact that the FA made that decision, some cracks are bolted because our rock can be less than optimal for trad and here is why. That second picture looked like it would take gear perfectly, right? Let’s take a bit closer look:





As you can see the entire surface of the rock is just one big flake wrapped around the inner rock. The tan rock is the outer layer and the grey rock is the much more solid inner layer. Place a cam on the tan and you might be in trouble, place it on the grey and you’re okay. Granted I have taken falls on gear in the crack in the above photos and had it hold, but I think those last two photos make it a bit easier to understand why bomber looking placements can sometimes pull. Granted, in those photos the separated flake an inch from the crack should warn you off, but there are places where the inner layer does not show itself and there are no obvious visual warnings that the rock is separated.

However, that issue I described is less important. Although that rock had a flakey outer layer, it seems to be more reliable than this rock:



This is what many of our cracks look like. At first it looks like a standard crack that would provide good gear. But unfortunately that is not the case. This is the cornflake phenomena I referenced above. This layer of rock is basically just a lot of flakes glued together. Often times when someone places a cam in rock with this type of texture in Hawaii, the cam lobes crush the flakes on a fall and dislodge them from the main body. At that point the cam is basically sitting in a field of marbles.

Lastly, the exact crack I placed the blue Alien in:



I placed it about 2/3rds up the pictured crack. It held because although the rock does have the same type of outer mantle shown in the other photos, there is no space between the outer layer and the inner layer, and the outer layer is well fused to the inner layer which creates a much more solid piece of rock. But as you can see, the differences are rather subtle and can be easy to miss. All of the cracks in this post "look" like they would offer a textbook cam placement, parallel rock, seemingly high density rock. But as I have pointed out, looks good and is good are not necessarily one and the same which is why I always try to have more than one piece between me and the ground regardless of where I am climbing.


(This post was edited by USnavy on Apr 27, 2012, 5:36 PM)

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