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Brian in SLC
Social climber
Salt Lake City, UT
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Looks like it broke, after bending, at or near the first glue groove.
Sure does. Which makes sense.
Depending on how they get the grooves in the bolt, that might be a contributor too (ignoring that the bolt shouldn't see much load in that area though).
I seem to recall, early in my climbing career, deciding that putting a few extra teeth in an ice tool pick seemed a good idear. Used a triangle file. Wasn't long before that pick snapped right at the new tooth area.
The Tortugas I've looked at (Liberty here in SLC is/was the distributor) all seemed finished pretty nicely in the groove area (don't recall any sharp inside corners).
-Brian in SLC
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Chiloe
Trad climber
Lee, NH
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A big hefty steel bolt in there, and this does not happen.
You sound so certain.
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Dr. Rock
Ice climber
Castle Rock
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You mean like scoring a glass rod before you snap it, of course.
I just opened up a Climbing Company.
We make Berrilium Quick Draws.
The feature Boron keepers.
Super light.
Hang off them all day.
Any takers?
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Ain't no flatlander
climber
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A bad placement is a bad placement. The metal doesn't matter when the user screws up.
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mewalrus
Trad climber
Minneapolis, MN
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"The bolt was placed under a roof, vertically, facing downwards. "
Well looking at the ushuba bolt its obvious that the design is not optimal for vertical placement as vertical placement will create torque when the bolt is fallen on, the offset eye causes this where as, in a horizontal placement it prevents torque.
I would say its not appropriate to use these offset bolts in a dead vertical placement.
" A bad placement is a bad placement. The metal doesn't matter when the user screws up."
A bolt not designed for the loading direction it receives will matter, the metal won't necessarily matter.
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couchmaster
climber
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Has anyone contacted Ushba yet? They have lots of Ti bolts out there in the world, it's a product considered superior to all others.
Edit, to those who think that the placement was wrong, think about that for a moment, there's no way in hell a bolt/hanger is as good as this combo should be in that application.
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mewalrus
Trad climber
Minneapolis, MN
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A symmetrical stainless steel glue in should be used in this application.
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stevep
Boulder climber
Salt Lake, UT
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Dr. R, you're being a little too sure of yourself. There's not that much difference in strength between Ti and steel bolts. As for a weld-related failure, I'd expect that to be much closer to the weld.
But basically there are too many variables to judge. If we assume that the bend and the break are related (likely but not definite), then either the bolt was installed sticking too far out allowing the bend and failure, or it was set deep, but not enough glue was used and the rock around it crumbled, allowing the same type of failure as if it had been placed sticking too far out. In either case, a steel bolt would not necessarily have been much better.
If the failure was a combination of force-related stresses and some sort of chemical weakening, then most likely the Ti bolt would have lasted longer.
If it just happened to be one bolt with a flaw, well, sh!t happens. Even 6 Sigma standards don't mean there are never flaws.
We'll know none of this without an inspection of the bolt and some more detailed information on what the placement looked like before the break.
At any rate, there's alot of these things out there, and based solely on that bend, I'd be pretty surprised if this represented anything that would cause a recall. So I'd take your dollars to donuts bet. Your $12 to my 12pack of donuts?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Ain't no flatlander wrote:
A bad placement is a bad placement. The metal doesn't matter when the user screws up.
This quote should be put up somewhere as a big flashing neon sign.
It was a bad placement.
Deal with it...
Edit: I will Paypal $100.00 to the first person who offers verifiable photographic
proof that that bolt was placed with the eye flush with the rock, and in a way that
the main forces to the bolt are consistent with the way for which is was designed.
I'm willing to put my money where my mouth is. Where, oh where are the pics?????
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graniteclimber
Trad climber
Nowhere
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Hardman/Slime: "And NOR CAL, oh my god, what an idiot. He writes that (I paraphrase) that since his friend had an accident with an Ushba ascender while rope soloing (NOT an approved use for that device or any ascender), that he doesn't like ANY Ushba products. That's cool Nor Cal, they don't like you either."
Ushba marketing copy (on any number of web sites): "Compact, lightweight, and easy to use, the Basic Ascender is rope-friendly, extremely strong, and will not slip on icy or muddy ropes. These fail-safe features combine to make it an excellent choice for top-rope solo and self-belay applications.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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It's idiotic to Solo TR with no back up. End of story.
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Darryl Cramer
Social climber
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I acquired a bunch of the Tortuga anchors to use in sandstone and seaside cliffs in WA. I placed one in a boulder in my front yard and beat the heck out of it with a sledge hammer – I couldn’t get it to break.
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Dr. Rock
Ice climber
Castle Rock
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They take out the Titanium pedal spindles and brake binder bolts most of the time when building road bikes.
Some people even change out chain ring bolts.
Snappy Gator, that Ti stuff.
It took me 5 minutes on Google to come up with that welding article.
Just type in
"Titanium" + "welding" + "brittle" etc and you will get a plethora of information.
I would put that failed bolt in a Safe Deposit Box until you figure out which barrister to retain.
If I were an Attorney, I would be all over this, salivating at the chops.
If the route sees heavy traffic, go for The Beef.
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JLP
Social climber
The internet
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This is turning into a retard fest.
If you have to surf Google to bring your knowledge up to the point where you feel like you can post something relevant - you probably can't.
Ti by itself is rather weak. The alloys are pretty strong. SS comes in many flavors as well. Some are stronger than some of the Ti alloys, some not.
The break didn't happen anywhere near the weld.
Bolts break all the time for various reasons, so you should consider that when you are out climbing.
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Forest
Trad climber
Tucson, AZ
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They take out the Titanium pedal spindles and brake binder bolts most of the time when building road bikes.
Some people even change out chain ring bolts.
??? um, is there a typo in there somewhere? What do you mean "they take out"?
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Dr. Rock
Ice climber
Castle Rock
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Again, it does not matter if there was a little slack hanging out.
You want a hanger that you can mis install and bend back and forth til hell freezes over without breaking.
Build stuff for the masses, expect the worse, and your product will survive.
You need a fudge factor.
Titaniun has no fudge factor.
It must be welded perfectly or else.
Easy to get a bunch of 3/8 inch round stock of various alloys.
Put it in a vice and bend it back and forth til it breaks.
Count the cycles.
It seems that Lord Slime is also the guy who designed this?
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Dr. Rock
Ice climber
Castle Rock
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Just some welding info.
I do not know if these were tig welded or not.
Could be a machine weld.
The weld looks real good, no under cutting, and no grinding needed.
Can't look at the HAZ (Heat Affected Zone) because of the black oxide, which is normal.
Ti dust is used in fireworks, interesting.
Anyway:
David Hoss wrote this for The Metal Fab Type Of Guy:
"Weld Preparation
Weld preparation should include removing any oil, grease, dirt, or grinding dust from the surfaces to be joined. Steam cleaning or an alkali dip in a dilute solution of sodium hydroxide can remove most of these contaminants. To remove the last remaining organic compounds just before welding, use a lint-free glove and methyl alcohol, acetone, or other chlorine-free solvent. Because most of these solvents have a low flash point, be sure they have fully evaporated before striking an arc.
On the most critical parts, using a small hot-air blower (hair dryer-style) to warm the part slightly ensures no moisture has condensed on the surface to be welded. Don’t overlook the fact that rubber gloves may contain chlorine as part of a vulcanizing process. Plastic gloves are recommended.
Pure Argon Applied Correctly
The argon must be 99.999 percent pure. Even if the argon is as pure as the 50 parts-per-million (PPM) range (99.995 percent), some yellow-straw discoloration can result. Many shops strive to maintain a 10-PPM contamination level during welding. If the color begins to mottle, or if it exhibits any hint of blue, the argon isn’t pure enough, or you’re not applying it correctly. Start the argon gas flowing for several seconds before using the high-frequency start. If you have enough shielding and the argon is being dispersed evenly over the part, you should see a uniform color.
Mottled or swirl patterns usually indicate too much argon is flowing (see Figure 1 ). Argon’s density is greater than air, so it tends to flow over the surface of a part in the same way water does. Where eddies occur, air can become mixed with the argon cover gas and create swirl patterns.
Figure 1
What really separates titanium welding from most other types of GTAW is the need for an argon cover on the weld’s back side. Wherever the titanium is heated, brittle alpha-case can form. For very complex parts with interior passages or parts that require a lot of welding repairs, glove boxes may offer an economical answer. For parts too large to fit through the glove box, special flexible polyethylene plastic bags, complete with attached gloves, can be used. Use a purge monitor to see when the bag contains clean-enough argon, strike an arc, and weld away. Working in airtight gloves, especially for extended periods, can be hot, but doing so is part of the challenge of working with titanium.
Finishing Up
The end of the weld is equally important. The titanium is hot, and the protective argon flow is still needed until the metal has cooled below about 500 degrees F. Color can be your best indicator of sufficient argon use. Some discoloration may occur beyond the HAZ and, depending on the criticalness of the weld, may be acceptable."
Here is some Heat Treatment info from TIMET:
"Heat Treating Titanium
Heat treatment of titanium fabrications is not normally necessary. Annealing may be necessary following severe cold work if restoration of ductility or improved machinability are desired. A stress relief treatment is sometimes employed following severe forming or welding to avoid cracking or distortion due to high residual stresses, or to improve fatigue resistance. Cleanliness of titanium parts to be heat treated is important because of the sensitivity of titanium to contamination at elevated temperatures. Titanium fabrications should be cleaned carefully prior to heating, using nonchlorinated solvents or a detergent wash, followed by a thorough water rinse. Handling following cleaning should be minimized to avoid potential surface contamination.
Most titanium grades are typically stress-relieved at about 1000°F (538°C) for 45 minutes and annealed at 1300°F (704°C) for two hours. A slightly higher stress relief temperature [1100°F (593°C), 2 hrs.] and annealing temperature [1450°F (788°C), 4 hrs.] are appropriate for the Grade 5 alloy. Air cooling is generally acceptable.
Although no special furnace equipment or protective atmosphere is required for titanium, a slightly oxidizing atmosphere is recommended to prevent pickup of hydrogen. Direct flame impingement for extended periods, leading to temperatures in excess of 1200°F (649°C), should be avoided because of the potential for contamination and embrittlement. Hydrogen or cracked ammonia atmospheres, also, should never be used, because their use would lead to excessive hydrogen pick-up, and embrittlement.
If a scale removal treatment, following a high temperature (1200°F; 649°C) anneal is not feasible, a vacuum or inert gas (dry argon or helium) atmosphere is recommended. Superficial surface discoloration, caused by annealing below 1200°F (649°C), may be removed by acid pickling in a 35% nitric acid – 5% hydrofluoric acid bath at 125°F (52°C). However, if long heating times or temperatures above 1200°F (649°C) have been used, a molten caustic bath or mechanical descaling treatment, followed by nitrichydrofluoric acid pickling, is necessary to remove scale."
You can pickle the stuff also.
More stuff from "Kenneth" at the Aerospace Engineers Forum:
"Cold reduction before after solution treating and before aging is not required for 6Al-4V Ti bolt material to achieve 160 ksi UTS. Typical aerospace bolt fabrication practice is to buy annealed material and to solution treat and age "blanks" in-house (after head forming/forging) to 160 ksi. The specifications they procure the material to require "heat treat capability" testing/certification of a sample of the as-shipped raw material after solution treament and aging (with no intermediate cold reduction) to the applicable tensile requirments.
I (like Wil) would be very, very cautious about the toughness of 6AL-4V Ti "pushed" to 180 k"
I bet the guy who wrote this gets a lot of dates:
" Abstract
Nanostructured Ti (100 -300 nm average grain size), processed by severe plastic deformation through equal channel angular pressing of commercially pure Ti rods after quasi-static compression (at 0.0004 s^{-1}strain-rate) of prismatic (2×2×7mm) samples has at low temperatures (77 and 4,2K) yield stresses two times larger than the initial CP-Ti, failure stresses ranging from 1.4 to 2.4 GPa. The shear failure phenomenon has been observed at 77 and 4,2K. Nanostructured Ti is absolutely thermomechanically unstable against catastrophic plastic shear under low temperature straining. The catastrophic plastic shear spreads through the whole section of the sample with a velocity close to the transverse sound velocity and has a dynamical character. It is supposed that the micro mechanism of the shear failure of nanostructured Ti consists in extending of the catastrophic shear by grain boundary dislocations. "
"EXECUTIVE SUMMARY
Hard alpha or high interstitial defects (HID) often, and erroneously, referred to as low-density
inclusions (type I) in titanium alloys, have been the focus of attention off and on since the
application of titanium to rotating components in gas turbine aeroengines. There have been
failures of components and, unfortunately, some loss of life associated with the presence of such
defects and a concomitant-reduced fatigue life. The early characterization of this class of defects
resulted in identifying a few key characteristics that are responsible for the reduced fatigue life of
titanium components that contain them. Chief amongst these characteristics is a higher hardness
than the nominal alloy due to interstitial (nitrogen, carbon, and oxygen) alloying at levels much
higher than the nominal alloy. Besides being hard and brittle, these nuggets of high interstitial
stabilization are refractory, relative to the melting temperature for the host titanium alloy, and are
slow to dissolve. This refractory nature, combined with the size of the initial seed, may permit
the nugget to survive, with its hardness characteristics, all the vacuum arc remelting (VAR)
process steps normally used to create a titanium ingot. This realization resulted in the institution
of triple VAR to replace the standard double VAR for premium-grade applications, resulting in a
significant reduction in occurrence of hard alpha defects."
Close Analogs: 4 other heat treatments of this alloy are listed in MatWeb.
Key Words: Ti-6-4; UNS R56400; ASTM Grade 5 titanium; UNS R56401 (ELI); Ti6Al4V, biomaterials, biomedical implants, biocompatibility
Component Wt. %
Al 6
Fe Max 0.25
O Max 0.2
Ti 90
V 4
Material Notes:
Information provided by Allvac and the references. Annealing Temperature 700-785ºC. Alpha-Beta Alloy.
Applications: Blades, discs, rings, airframes, fasteners, components. Vessels, cases, hubs, forgings. Biomedical implants.
Biocompatibility: Excellent, especially when direct contact with tissue or bone is required. Ti-6Al-4V's poor shear strength makes it undesirable for bone screws or plates. It also has poor surface wear properties and tends to seize when in sliding contact with itself and other metals. Surface treatments such as nitriding and oxidizing can improve the surface wear properties.
Physical Properties Metric English Comments
Density 4.43 g/cc 0.16 lb/in³
Mechanical Properties
Hardness, Brinell 334 334 Estimated from Rockwell C.
Hardness, Knoop 363 363 Estimated from Rockwell C.
Hardness, Rockwell C 36 36
Hardness, Vickers 349 349 Estimated from Rockwell C.
Tensile Strength, Ultimate 950 MPa 138000 psi
Tensile Strength, Yield 880 MPa 128000 psi
Elongation at Break 14 % 14 %
Reduction of Area 36 % 36 %
Modulus of Elasticity 113.8 GPa 16500 ksi
Compressive Yield Strength 970 MPa 141000 psi
Notched Tensile Strength 1450 MPa 210000 psi Kt (stress concentration factor) = 6.7
Ultimate Bearing Strength 1860 MPa 270000 psi e/D = 2
Bearing Yield Strength 1480 MPa 215000 psi e/D = 2
Poisson's Ratio 0.342 0.342
Charpy Impact 17 J 12.5 ft-lb V-notch
Fatigue Strength 240 MPa 34800 psi at 1E+7 cycles. Kt (stress concentration factor) = 3.3
Fatigue Strength 510 MPa 74000 psi Unnotched 10,000,000 Cycles
Fracture Toughness 75 MPa-m½ 68.3 ksi-in½
Shear Modulus 44 GPa 6380 ksi
Shear Strength 550 MPa 79800 psi Ultimate shear strength
Electrical Properties
Electrical Resistivity 0.000178 ohm-cm 0.000178 ohm-cm
Magnetic Permeability 1.00005 1.00005 at 1.6kA/m
Magnetic Susceptibility 3.3e-006 3.3e-006 cgs/g
Thermal Properties
CTE, linear 20°C 8.6 µm/m-°C 4.78 µin/in-°F 20-100ºC
CTE, linear 250°C 9.2 µm/m-°C 5.11 µin/in-°F Average over the range 20-315ºC
CTE, linear 500°C 9.7 µm/m-°C 5.39 µin/in-°F Average over the range 20-650ºC
Specific Heat Capacity 0.5263 J/g-°C 0.126 BTU/lb-°F
Thermal Conductivity 6.7 W/m-K 46.5 BTU-in/hr-ft²-°F
Melting Point 1604 - 1660 °C 2920 - 3020 °F
Solidus 1604 °C 2920 °F
Liquidus 1660 °C 3020 °F
Beta Transus 980 °C 1800 °F
So would you rather worry about all of that gobbledeegoop while your climbing, or go Bomber?
References for this datasheet.
http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MTP641
Looks like it's hangin out a bit.
Maybe they need to change the pic over at USHBA?
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tradmanclimbs
Ice climber
Pomfert VT
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I would totally bitch about the placement in that add if i ran accross it climbing, " dumb bastards didn't counter sink it"
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BKW
Mountain climber
Central Texas
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Topic Author's Reply - Aug 6, 2008 - 08:41am PT
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OK Hardman here is your cross section photo
I'll be in TM this weekend and we can settle then
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