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Best micro cam - morphed - Alien strength WARNING

patto

15-Jun-2009
2:37:15 PM

Also here is the write up on the recent testing of BRAND NEW alien cams.

http://www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=2149960;forum_view=recent_posts;page=unread#unread


IdratherbeclimbingM9

15-Jun-2009
3:47:03 PM

On 15/06/2009 patto wrote:
>Also here is the write up on the recent testing of BRAND NEW alien cams.
>
>http://www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=2149960;forum_view=recent_postspage=unread#unread

A good link.
User information; ... there are many photos associated with that link and it is slow loading as a consequence.

>Of those 22 cams, 13 were brand new

~> They were not all 'brand new' but nevertheless the results are very interesting.

I shall continue using my aliens, however I shall be treat(ing) them as only half their rated strength during use, to build in my own conservative buggery factor* for safety.

(*This involves no measurements at all and is purely psychological; ie an attitude of; it being better to fall on a big nut than a small one!).

It is a good link for those folk who already have aliens, to make themselves aware of the main issue; being the fact that they are not as strong as claimed.

Possible solutions till CCH quality assurance comes up to spec?

• If in doubt, double up your pro.
• Place bomber pro (G'day bomber! Hehx³), as soon as practical after a supposedly reasonable alien placement.
• If you run it out above an alien be aware of just how bold this action might be.

patto

15-Jun-2009
4:48:06 PM

On 15/06/2009 IdratherbeclimbingM9 wrote:
> They were not all 'brand new' but nevertheless the results are very
>interesting.

Sorry I didn't mean in any way imply that all alien cams tested were brand new. I was just saying that brand new cams were included. Naturally you can go back weeks and years to see other Aliens that have failed below strength. This is all old news really. This has been going on for years.

What is new though:
Evidence of systemic cam lobe mis-drilling
Money finally got put together for brand new Alien testing.

People have been waiting YEARS for CCH to pull their shit together. I doubt it will happen. That said I'm not going to be telling people not to use Aliens, thats their own choice. Personally I'm using them.


IdratherbeclimbingM9

15-Jun-2009
4:58:18 PM

No need to be sorry. I am just pedantic!
~> & I appreciated the update info.


ajfclark

15-Jun-2009
6:34:35 PM

On 15/06/2009 patto wrote:
>What is new though:
>Evidence of systemic cam lobe mis-drilling

There's been evidence of that problem with aliens for a long time. The cam angle testing site linked from the article was developed as a reaction to the problem. From the site:

The Cam Fitter was written by John Field in late November 2005 to help facilitate the replacement of defective CCH Orange Aliens.

Further coverage: http://www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=2148506

patto

15-Jun-2009
6:52:54 PM

On 15/06/2009 ajfclark wrote:
>On 15/06/2009 patto wrote:
>>What is new though:
>>Evidence of systemic cam lobe mis-drilling
>
>There's been evidence of that problem with aliens for a long time. The
>cam angle testing site linked
>from the article was developed as a reaction to the problem. From
>the site:
>
>The Cam Fitter was written by John Field in late November 2005 to help
>facilitate the replacement of defective CCH Orange Aliens.
>
>Further coverage: http://www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=2148506

I'm aware of the coverage. I said systemic because it seems possible that ALL alien cams have these issues, not just one bad batch. The bad batches were picked up because they were so bad that people could help but notice. These ones are more subtle but they have been consitantly off for years possibly over a decade.

I'm almost inclided to give CCH the benefit of the doubt on this one for the time being. I'd love to see what they have to say on the issue. I find it amazingly hard to believe that a company would systematically mis-drilled their cam lobes. But at the same time the evidence seems to be there. After all it makes no sense to design a logarithmic spiral for the cam and then not place the hole at the centre. That said metolius's super cam isn't a pure logarithmic spiral, the curve tightens near the tips to improve the cams resistance to tipping out. But this was part of the design.

one day hero

15-Jun-2009
7:25:55 PM

On 15/06/2009 patto wrote:
>Don't try bring into question my facts when you haven't even bothered
>to try to confirm them. As far as I'm concerned these figures are correct,
>I researched them from multiple sources.

So, you've found these figures on multiple chatrooms? If your figures are right, my aliens should slip out of cracks where other cams hold. They do not, the opposite is sometimes true. Something funny is going on.
>
>>
>> They also rate to a known standard (3omega),
>I can't find anything about this on the CCH website. Would you please
>tell me why you believe this? Eitherway they ABSOLUTELY fail 3sigma rating
>as shown by the recent testing of new cams.

This was me quoting you, chocky got the colour of text wrong
>>
>I'm hanging CCH to dry because MANY cams are failing, sometimes significantly
>below their rating strength. Their poor brazing and initial denial of
>it was just scary. So you are calling BD a company of liers now? WTF?
> Besides how does calling into question other companies policies work as
>a defense of CCH?

I have a BD cam which they claim holds 12kN. Someone tests one and breaks it at 9kN. I once had a BD propaganda leaflet telling me all about how the 3 sigma system they had in place meant that every single BD unit was super duper......The person who wrote that bit in the catalogue was a goddamn liar

Given the info on the strength testing link, it would seem that CCH also employs liars to print their ratings. Although, since they don't claim to have a 3sigma system it could be argued that some cams are allowed to fail weak as long as the average is right.....not that that would be a good look for CCH either

I don't think that questioning another company is a defence of CCH, just that you have to buy your cams somewhere.


ajfclark

15-Jun-2009
7:40:29 PM

On 15/06/2009 patto wrote:
>I'm aware of the coverage. I said systemic because it seems possible
>that ALL alien cams have these issues, not just one bad batch.

Sorry, I misunderstood you on that one.

>I'm almost inclided to give CCH the benefit of the doubt on this one for the time being. I'd love to see what they have to say on the issue. I find it amazingly hard to believe that a company would systematically mis-drilled their cam lobes. But at the same time the evidence seems to be there.

I'm sure a lot of people would love to hear something from CCH.

one day hero

15-Jun-2009
7:41:31 PM

I should repeat, I have no problem with BD cams, 9kN is strong enough. I don't like propaganda and half reporting of test results. If they pull test every unit to 7kN, super, stamp on the unit "7kN Tested, actual strength 99% likely to be 14kN" That would be honest reporting with the info they have.


ajfclark

15-Jun-2009
7:55:39 PM

On 15/06/2009 one day hero wrote:
>I have a BD cam which they claim holds 12kN. Someone tests one and breaks it at 9kN. I once had a BD propaganda leaflet telling me all about how the 3 sigma system they had in place meant that every single BD unit was super duper......The person who wrote that bit in the catalogue was a goddamn liar

3 sigma promises no such thing. Even BD's own site only says 99.87% should fail at or above the rated load. There's room for something to fail at less than the rated load and as with all statistical measures there's always the risk that the samples used for destruction testing are not representative of the whole population for some reason.

It does however give more faith than only pull testing each unit to half its rated load...

patto

15-Jun-2009
8:01:18 PM

On 15/06/2009 one day hero wrote:
>I should repeat, I have no problem with BD cams, 9kN is strong enough.
>I don't like propaganda and half reporting of test results. If they pull
>test every unit to 7kN, super, stamp on the unit "7kN Tested, actual strength
>99% likely to be 14kN" That would be honest reporting with the info they
>have.

3sigma is NOT propaganda it is probably THE most appropriate way of issuing a rating of breaking strength. Pull testing every unit is another way of proof of quality but it does not give you a breaking strength of a unit.

If you have any other appropriate way of rating a climbing gear's breaking strenght then please inform us.

owl

15-Jun-2009
10:14:00 PM

I bought a Master cam. Have you ever noticed that when you bend the centre, the cam lobes retract. I felt uncomfertable with the cam so removes some of the spring before the head. Hard to explain, so I have included picture.

One Day Hero

15-Jun-2009
11:13:14 PM

On 15/06/2009 patto wrote:
>3sigma is NOT propaganda it is probably THE most appropriate way of issuing
>a rating of breaking strength. Pull testing every unit is another way
>of proof of quality but it does not give you a breaking strength of a unit.
>
>If you have any other appropriate way of rating a climbing gear's breaking
>strenght then please inform us.

O.k. I will. You said that you weren't worried about aliens failing at 8kN. Good, pull test cams to 7 or 8 kN (whatever they can handle without permament deformation) give that as tested strength. Then you have in your hand a cam which you know 100% will not break at the load stamped on it. Further to that, if you want, add a breaking strength of the weakest unit you've EVER tested! If you break 1000 units at 14kN and 1 unit at 10kN, stiff shit, your cams should be rated "ultimate strength 10kN". Simple

One Day Hero

16-Jun-2009
12:02:59 AM

On 15/06/2009 ajfclark wrote:
It does however give more faith than only pull testing each unit to half
>its rated load...

Are you sure? Just say I work on the production line making masterbeta cams. Instead of weetbix for breakfast this morning I had fifteen cones. When I reach for the brazing rod on one occasion at 10:15am I instead pick up a banana. Now, surely the 3 sigma rating system will pick up the errant bananabraze........but it doesn't. How about the stringently updated long term mean batch test results?........nope, the bananacam is not the one selected for batch testing.
So now afj wanders down to the local gearshop where he cops some spray handed down from the wholesaler, handed down from the company rep and firmly believes that 3sigma makes his masterbeta cam (not the average of all masterbeta cams, but his one particular masterbeta cam which he just purchased) absolutely bomber.....when in actual fact it's held together with banana!
On the other hand, if each one were proof tested (and this goes for the ridiculous, badly brazed aliens as well) the mistake would never leave the factory and manufacturing process errors could quickly be corrected.

If you really need your cams to hold 14kN, afj, I am rather impressed. You must give 'er pretty hard!
I remember when WC talked about reducing the thickness of cable on their Rocks because they had never had a reported failure in the field. Turns out it's very hard to make 10kN in a real world trad climbing fall. Doesn't seem to happen very often, if at all. Given this, I would way prefer an 8kN test on every piece than a highly probable 14kN but with the possibility of bananacams.


ajfclark

16-Jun-2009
8:28:19 AM

On 16/06/2009 One Day Hero wrote:
> Given this, I would way prefer an 8kN test on every piece than a highly probable 14kN but with the possibility of bananacams.

The more I think about this, the more sense it makes.

patto

16-Jun-2009
10:14:41 AM

On 15/06/2009 One Day Hero wrote:
>On 15/06/2009 patto wrote:
>>3sigma is NOT propaganda it is probably THE most appropriate way of issuing
>>a rating of breaking strength. Pull testing every unit is another way
>>of proof of quality but it does not give you a breaking strength of a
>unit.
>>
>>If you have any other appropriate way of rating a climbing gear's breaking
>>strenght then please inform us.
>
>O.k. I will. You said that you weren't worried about aliens failing at
>8kN. Good, pull test cams to 7 or 8 kN (whatever they can handle without
>permament deformation) give that as tested strength. Then you have in your
>hand a cam which you know 100% will not break at the load stamped on it.
>Further to that, if you want, add a breaking strength of the weakest unit
>you've EVER tested! If you break 1000 units at 14kN and 1 unit at 10kN,
>stiff shit, your cams should be rated "ultimate strength 10kN". Simple

One day hero it is clear that you still don't understand. Pull testing cams to 7 or 8kN is proof testing. This is a sepparate issue. I am not saying that this is bad.

The breaking strength based on 3sigma designs IS already HIGHER than the weakest unit they EVER tested. Unless you are suggesting that they are pulling 1000s in every batch. The solution you suggest is unscientific and tells you nothing about the unbroken cams.

3sigma is a statistical process that tells you the unbiased population breaking strength based on a sample. (It wont give you as good results as breaking every cam but breaking every cam wont leave any to climb on!)

patto

16-Jun-2009
10:24:07 AM

On 16/06/2009 One Day Hero wrote:
>On 15/06/2009 ajfclark wrote:
>It does however give more faith than only pull testing each unit to half
>>its rated load...
>
>Are you sure? Just say I work on the production line making masterbeta
>cams. Instead of weetbix for breakfast this morning I had fifteen cones.
>When I reach for the brazing rod on one occasion at 10:15am I instead pick
>up a banana. Now, surely the 3 sigma rating system will pick up the errant
>bananabraze........but it doesn't. How about the stringently updated long
>term mean batch test results?........nope, the bananacam is not the one
>selected for batch testing.
> So now afj wanders down to the local gearshop where he cops some spray
>handed down from the wholesaler, handed down from the company rep and firmly
>believes that 3sigma makes his masterbeta cam (not the average of all masterbeta
>cams, but his one particular masterbeta cam which he just purchased) absolutely
>bomber.....when in actual fact it's held together with banana!
>On the other hand, if each one were proof tested (and this goes for the
>ridiculous, badly brazed aliens as well) the mistake would never leave
>the factory and manufacturing process errors could quickly be corrected.
>

You are AGAIN mixing up breaking stength ratings with QC.

3sigma is about population sampling and determining the expected minimum population breaking strength. IT IS NOT ABOUT QUALITY CONTROL. It is only valid if quality control is up to standard and production is consistant. 3sigma loses its validity if you have a highly variable cam output. It does not pick up outlying manufacturing defects or mistakes.

Quality control is an entirely different beast. It concerns maintain consistancy in a production line and ensure mistakes don't happen.


foreverabumbly

16-Jun-2009
11:01:54 AM

On 16/06/2009 patto wrote:
>
>3sigma is a statistical process that tells you the unbiased population
>breaking strength based on a sample. (It wont give you as good results
>as breaking every cam but breaking every cam wont leave any to climb on!)

Im not a big fan on statistical proof and averages. that .35% (or whatever) that fail the 3sigma rating has to be out there. When I think about that and I look at my cams, I figure it raises to 50% - either its a good cam or its a bad cam.

millions to one happen all the time. We call it being lucky or unlucky. Like last week I found $5 in a drain at uni, normally I wouldnt look down at all, but to look down AND find 5 bucks is pretty damn lucky. That sucker bought me two coffees that day. Ive looked again every day since - and I doubt it would happen again. Million to one (or maybe 99.85% it wont happen)

Or if you put half your body in the freezer, half your body in an oven. Then average it out. dont worry cause your fine.

For me, companies spraying about sigma3, is like them saying "dont worry, almost all our cams are good. Almost..." or "hey guys, .15% of our products are faulty, but we are not going to tell you which ones. Its a lucky dip. 0.15 may not seem a lot but concidering how many we make and how many countries we are sold in...good luck."

My point is a statistical formula like sigma ratings isnt going to fix a cam thats broke, nor will it point out the broken ones. You should be checking all your gear and never put blind faith in anything.

Me, I still use my aliens cause Ive had the (mis?)fortune to test them on several occasions. Though I concede I wouldnt buy any new ones.

patto

16-Jun-2009
12:02:04 PM

foreverabumbly you still are missing the point.

You cannot give a 100% surity of a breaking strength for a cam. Sure you can pull test every cam but still from a scientific point of view you cannot give a cam an accurate estimated breaking strength rating without such statistics.

As said before 3sigma doesn't cover manufacturing defects and flaws outside of design

And foreverabumbly, I and others aren't putting 'blind faith' in anything. I'm just attempting to explain 3sigma to people like you who don't understand it.

mikl law

16-Jun-2009
12:06:19 PM

Saw a guy testing at the New River Rendezvous, one alien pulled at the braze at 4 kN. Now that is a worry.

There are very few falls that exceed 8kN, but many that would exced 4kN

There are 84 messages in this topic.