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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Original Post - Sep 16, 2010 - 04:04pm PT
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Today's lunchtime goof off.
I was looking for cheap SS hangers but the Acme ones ($1.75) are seldom available. I found Fusion ones for $2.50 and bought some. The folks at Fusion said they had some test data and sent me a certificate from an engineer that indicates one was broken in the strong, shear, direction, failed at something like ~7100 lbs (~31.6 kN) and referenced a ANSI standard. Fusion is in Orange county and seems to target the rescue and tactical markets. They seem to be located in a strip mall or something. Too far away for me to go check out.
http://fusionclimb.com
I decided to test one in the weak direction. I set it up with junk that was lying around. If you don't like my junky test fixtures, I'd be happy to let you buy me something better.
I attached the hanger to a steel plate with a 3/8" bolt and nut. The nut was on the hanger side. I pulled it and at 3150 lbs (14 kN) the cheap bolt I was using snapped.
I set it up again with a higher grade bolt (a cap screw actually) and pulled it again. At 6850 lbs (30.5 kN) the nut pulled through the hanger and the nut split in half. Since the hole in the hanger was seriously over sized now, I considered the test done.
I don't have access to the European standards but Petzl shows some info in their literature. They say 25 kN in the usual shear direction, 18 kN in the reverse shear (up) direction and 18 kN in the weak pull out direction.
I'd say the hanger is the strongest link in the chain. More likely the bolt or the biner will fail first
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nature
climber
Whereverland....
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Sep 16, 2010 - 04:07pm PT
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did Weld_It send you any of his shuts? I bet your machine would bust.
that dude knows radness.
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Thorgon
Big Wall climber
Sedro Woolley, WA
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Sep 16, 2010 - 04:42pm PT
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Pretty Damn tough! I checked their website, but didn't see 3/8" SS, but they make hangers with rap rings and chains. Worth looking into, made is USA?
Thor
Weld_It shuts can KNOTT be broken! LOL
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Reply - Sep 16, 2010 - 05:50pm PT
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I bet your machine would bust.
Machine goes to 60,000 lbs. I'll take the bet, send the parts and a bundle of 100 $ bills.
I checked their website, but didn't see 3/8" SS
Their website is mislabeled, they sell a 10mm and a 12mm. I pointed this out to them but I guess they haven't got to it. I don't know where they are made.
Dang, now I see them on the web for $2.10
http://www.outdoorpros.com
Dudes ripped me off!
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T Moses
Big Wall climber
Paso Robles
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Sep 16, 2010 - 09:19pm PT
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I agree "RAD!!!!!!!!"
I recommend using washers between the nut and the hanger. This spreads the load out. Good grade 8 nuts bolts and washers would make your testing go a little farther.
I agree that hangers are not the weakest link in the system. They are often stronger than the bolts they are attached to.
Can you test in the regular load direction? Do you want to test some other stuff?
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Thorgon
Big Wall climber
Sedro Woolley, WA
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Sep 16, 2010 - 09:24pm PT
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Testing for Theron Moses, YOU HAVE ARRIVED!!!
Good stuff,
Thor
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Dr.Sprock
Boulder climber
I'm James Brown, Bi-atch!
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Sep 16, 2010 - 09:37pm PT
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Banquo, do you have a Reverso 3 laying around?
60,000 is ok,
but i know the dude who thrust tested the Apollo rockets,
used a strain gauge off a locomotive scale,
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Reply - Sep 16, 2010 - 09:53pm PT
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I thought about using a washer but then eveybody has to use one at the crags. I decided to err on the consrvative side. You can actually get a larger nut threaded 3/8 too. Just modeling what I see in the field I guess.
I can test pretty much anything static to maybe 300,000 lbs. Dynamic to 60,000 lbs. Used to test railroad stuff with something like 30 kips and 3 million cycles. The real question is do I have time, want to or have something better to do.
No reverso 3, I saw one once. I have a 20 year old ATC and an even older Lowe tube though.
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Thorgon
Big Wall climber
Sedro Woolley, WA
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Sep 16, 2010 - 11:01pm PT
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I am definitely a fan of independent testing!
Thor
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cragnshag
Social climber
san joser
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Sep 16, 2010 - 11:33pm PT
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I thought you said you were busy... so this means you have time to climb
this weekend? Perhaps we can do some dynamic testing of in-situ mank
gear by the falling method.
I'll gather up some quarter inch hangers for next week's lunch-'break'
and an acme and fixe 3/8 and one of Dingle's 1/4" SS hangers.
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mucci
Trad climber
The pitch of Bagalaar above you
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Sep 17, 2010 - 03:06am PT
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Sweet!
I put those hangers at most belays on a route this summer.
Bombproof, and they have the "Fixe dimples" on the back, but more of them and in a different configuration.
A serious + for me. They seat very well.
Thanks for the peek!
Mucci
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Reply - Sep 17, 2010 - 10:42am PT
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This was pretty quick and dirty testing. Obviously, I could have used a better bolt and probably should have used a washer. Even so, I think the hanger is strong enough and that was my goal - satisfy myself that they are good enough. I can do other tests on these hangers but won't until I figure out what to test, how to test and what criteria I'm looking at. In other words, less quick and less dirty. I was concerned that the source had only tested one and had only tested it in the strong direction. Not very statistically significant.
I am curious what Theron would like to break (feel free to send me an email). At some point scale of project, scope of project and liability come into play but I like breaking stuff and have a lot of fun testing things. Small projects are free - or at least back scratch. If it gets too big we have to talk about contracts and accounts. I have or have access to quite a bit of equipment. Load cells, rams, jacks, accelerometers, stain gauges, deflectometers. A lot of this stuff is portable and can work on 12v. A bit more trouble with access but I can also get to material testing things like hardness testers and even a scanning electron microscope. Fatigue testing is possible but certainly not quick and dirty.
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Jingy
climber
Somewhere out there
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Sep 17, 2010 - 11:05am PT
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feeling safer already
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T Moses
Big Wall climber
Paso Robles
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Sep 17, 2010 - 04:12pm PT
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I was just interested in doing some quick and dirty testing. Possibly some stuff that doesn't get tested usually. Hooks, rivet hangers, random climbing stuff. It would be cool to see the failure mode and see how they might be reengineered to be better. Nothing serious. Post on here on St and let the flaming ensue. I have considered building my own testing fixture but have been to busy with other stuff (T2's & D5's).
I can definitely do some back scratching depending on what kind of climbing you do or what you need fabbed.
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Reply - Sep 18, 2010 - 09:09pm PT
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I went downstairs to the garage and looked at what I have in my own junk pile and I found some load cells with digital readouts and a hydraulic cylinder with pump. There may be more down there in the boxes.
I have a 12-ton hollow cylinder with pump. Hollow is good because you can pull on things (tension test) by running a rod through the cylinder. Dayton is gone but the current substitute is:
http://tinyurl.com/2eebvf7
The big green load cell is 2000 lb capacity and good for tension or compression. It was 7/16 NF on one end and 1/2 NF on the other. Right now I have it set up with two 1/2" AL plates as a load platform.
The little green load cell is a 2000 lb capacity with 3/8 NF on each end. I think this is tension only.
The big silver load cell is a 5000 lb capacity with a 6-hole plate mount on one side and I think a 1/2" NF on the other end. LCHD-5K Specs here:
http://www.omega.com/Pressure/pdf/LCHD.pdf
Little silver one is for bolt torque/tension testing. It is 50,000lb capacity. I have several sets of spherical washers to go with this. LCWD-50k specs here:
http://www.omega.com/Pressure/pdf/LCWD.pdf
I have no idea what a rivet hanger might break at but the little green 2 kip load cell and the hollow cylinder might just do the trick. I can get other load cells if we have some idea what force we are talking about.
I haven’t used any of this junk in a few years and some of it is new and has never been used. I might be talked into coming down to SLO town for a visit to break stuff or even leave it on loan.
More complex things will have to be in the labs at the university where I teach.
Thoughts?
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donini
Trad climber
Ouray, Colorado
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Sep 18, 2010 - 10:33pm PT
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Who has ever seen a bolt hanger fail?
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Strider
Trad climber
one of god's mountain temples.... ಠ_ಠ
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Sep 19, 2010 - 12:31am PT
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Leeper
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Reply - Sep 19, 2010 - 01:53am PT
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Who has ever seen a bolt hanger fail?
Good point, what does fail? My impression is that the overwhelming majority of failures are pilot cockpit errors not gear failures. New hangers are so much stronger than the bolts and carabiners, I don't really get it either. Not much of the equipment we have these days has any real chance of failing but tip out a cam in a shallow placement and you can fail.
30 year old, rusty leepers can fail but how many people have been hurt? Actually, I don't know but I would be surprised to hear if it was very many.
Outside of sport and gym climbers, how often do we actually fall? I fell twice this year but that's quite a lot for me. Both times on gear I placed. A #6 stopper at Pinnacles (don't want to do that again) and once on one of Bob's Aliens in the valley. Gear held, I failed.
That said, I think it's a good idea to test a few hangers just to be sure.
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