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From the maufacturers specs:

Note: kn = 224.8 lbs +/-

All figures are for the cable only. This does not include loops, over edges, tight radius applications or any funny business.

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Re: BD Stoppers–Bounce Test Data

From - Tue Feb 16 14:36:39 1999
From: Chris Harmston <chrish@xxxxxxxxxxxx>
Newsgroups: rec.climbing

I have measured forces up to 1000 lbf while bounce testing. I was using
BD Etriers and bounced with about a six inch free fall bounce. It is easy
to break small Stoppers if vigorously bounce testing. I weigh 190 lb.

I have seen several small stoppers break in the field due to bounce
testing and due to lead falls.

Rated strengths are stated as 3 sigma failure loads. There is not a 20 to
30% buffer. They break close to what they are rated. 3 Sigma is three
standard deviations below the average breaking strength. Average batch
test results (n = 10) range from 600 to 700 lbf for #1 and #2 Stoppers.
Batch standard deviations range from 6 lb to 50 lb. When combined into a
years worth of data our rating computes to 450 lbf. The weakest sample I
have seen in the last year failed at 535 lbf. The strongest failed at 808
lbf. 3 Sigma means that there is a 99.87% chance that the sample will be
stronger than the rating. This also means that there is a 0.13% chance
that a sample will fail below the rating. All this data is for brand new
equipment that has never seen any fatigue due to placement, removal,
falling on, bouncing on, etc. These small units get worn fairly quickly
and can break eventually. Inspect your gear often. If you have to use
these for lead protection then follow the advice of most of this group.
Back them up. Sometimes the only option you have is a small nut. Better
than nothing in many situations. Beware of the limitations of your gear
though. Chris

On Tue, 16 Feb 1999 mdimeo@xxxxxxxxxxxxx wrote:
>In article <36C8F69A.82BF48A1@boeing.com>,
> Mike Garrison <mike.garrison@xxxxxxxxxx> wrote:
>> ratagonia@xxxxxxxxxxxx wrote:
>> > Catalog say 2kN or 450 lbf for #1 & #2. Not hard to generate this kind of
>> > load in a fall.
>> That’s an understatement. My body weight is close to 1 KN.
>> Just jumping up and down I can generate about 2 KN.
>
>Ooh, a verifiable experiment. I like it. How about you try it out?
>I’ve always wondered how much force a bounce test really generates.
>Clip a biner to a bolt low to the ground. Slide the head down a #1 stopper.
>Clip one end to the bolt biner. Clip an aider or sling to the other end.
>Don safety glasses. Bounce. See if you can break it. I’m really curious.
>
>Off the top of my head, I’m betting biner flex, aider stretch, etc. will
>prevent breakage. Time to find myself a low bolt, though my weight is only
>around 0.73kN.
>-m@

Chris Harmston (chrish@xxxxxxxxxxxx).
Quality Assurance Manager. Materials Engineer BS, ME.
Black Diamond Equipment Ltd.
2084 East 3900 South, SLC, UT 84124 phone: 801-278-5552

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Rivet Hanger question

Russ Walling writes to Chris Harmston @ BD:

>Not sure if you have seen these rivet hangers guys are making now where
>it is a self tightening loop that goes around the rivet. Like a cinch
>loop in the end of a cable strand, formed by backtracking through a
>swage sleeve, that then goes to a clip in loop. Our tests show them as
>being a bit suspect. I don’t like the way the stop on the cinching
>end butts up against the sleeve used to contain the two wires. It seems
>that the strength of the unit is dependent on the cross or tearing
>strength of the keeper sleeve instead of the cable strength. There
>seems to be a lot going on including deformation of the sleeve and the
>stop sleeve. Whaddya think?

Chris replies:
Sounds funky. I have never used anything except small Stoppers for
rivets. I have not seen this device you are talking about. I think I
understand and it sounds funky to me as well. What kind of testing have
you done? If you want me to test some things I can help out (I have no
idea what kinds of testing capabilities you have).
Later. Chris

Chris Harmston (chrish@xxxxxxxxxxxxx).
Quality Assurance Manager. Materials Engineer BS, ME.
Black Diamond Equipment Ltd.
2084 East 3900 South, SLC, UT 84124 phone: 801-278-5552

DISCLAIMER: Unless otherwise indicated, this correspondence is personal
opinion and NOT an official statement of Black Diamond Equipment Ltd.

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Rivet Hanger question, the test.

Chris at BD writes:
I have completed the testing. Interesting.

Your standard rivet hangers are identical to loops. The cinch hangers are
half as strong as your standards. I will send you a copy of the test
report in the mail.

Quick summary.

Average data:

Loop #1 886 #2 1649 #3 2867 #5 2821
Std. #1 902 #2 1655 #3 2838
Cinch #1 577 #2 1034 #3 1453

Standard deviations range from 12 to 115 throughout all groups.

Overall these can all hold bodyweight and moderate bounce testing. I
would be a bit worried about bounce testing the #1 cinch. I certainly
would not want to fall on any of the #1’s or the #2 cinch. These are
pretty strong overall though. Even the weakest are comparable to the
bending strength of most specialty small hooks.

Why would you want the largest cable sizes for rivet hangers? My guess is
that if you have a large enough rivet or bolt head you can get a stronger
piece of pro. The very few rivets I have seen would not be able to accept
the larger diameter cable???

It seems that there may be an advantage to the cinch type. They will not
allow the moving swage to release too easily. It seems to me that there
is an increased risk on the standard design for the swage to slip down and
increase the chances that the hanger will fall off the piece. I have
never used anything except small stoppers for this and have not had any
fall off either. I would be interested in your comments on these.

Hope this helps.

Chris Harmston (chrish@xxxxxxxxxxxxxx).
Quality Assurance Manager. Materials Engineer BS, ME.
Black Diamond Equipment Ltd.
2084 East 3900 South, SLC, UT 84124 phone: 801-278-5552

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Rivet Hanger question, the test, pt. 3

On Wed, 3 Feb 1999 FishProductsInfo@gmail.com wrote:
>In a message dated 2/3/99 8:30:08 AM, chrish@xxxxxxxxxxx writes:

FishProds writes:
>These are close to the numbers I got. We rate
>the #1 at 700, the #2 at 1500, and the #3 at 2300. Of course, YMMV. We never
>did rate the #5. Best guess would be 3900.
>thanks for the info!
>adios,
>Russ