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Cobra Anchors -- Reviews?

DrRockso RRG · · Red River Gorge, KY · Joined Sep 2013 · Points: 815

The guys I spoke to at Powers indicated that there were no planned changes to be made to the SS PB at this time.

kennyp · · Vegas · Joined Apr 2010 · Points: 75

I know the 3/8 PS Power Bolt + isn't ideal but it still seems better than the Cobra:

For 3000 PSI Normal Weight Concrete:
3/8 x 3.5 Power Bolt: Ultimate Tension: 5195 lb; Ultimate Shear: 6815 lb.
3/8 x 4 Cobra Super Sleeve: "Pull Max": 2800 lb.; "Shear Max": 3000 lb.
3/8 x 2.75 Power Bolt+: Ultimate Tension: 4425 lb; Ultimate Shear: 3990 lb.

Allowable Loads:
3/8 x 3.5 Power Bolt: Tension: 1300 lb; Shear: 1705 lb.
3/8 x 4 Cobra Super Sleeve: "Pull Safe": 700 lb.; "Shear Safe": 750 lb.
3/8 x 2.75 Power Bolt+: Tension: 1105 lb; Shear: 1000 lb.

To me that Power+ Plus seems way better than the Cobra, and the Power+ is supposed to better designed to work in cracked concrete (more like real rock?)

Leftwich · · Unknown Hometown · Joined Oct 2009 · Points: 10

Has anyone tried climbtech's legacy bolt?

DrRockso RRG · · Red River Gorge, KY · Joined Sep 2013 · Points: 815

I've tried the legacy bolt, it's a good bolt just expensive and a tad short for the soft sandstone I bolt in. Would probably be more popular if they could get the cost down a bit.

Greg Barnes · · Unknown Hometown · Joined Apr 2006 · Points: 2,060

I was unable to remove a Legacy bolt from granite, and another was barely removed during testing in hard sandstone.

Anyone who intends to use them for an area should first get 10 of them to test removal method in your local stone.

I'd strongly recommend that you torque to no more than the minimum mentioned torque with the Legacy bolt, the bolts seem to stretch easily. I see they've changed it from a torque range to a guide torque of 20 ft-lbs, but that's what I used in granite and was unable to remove using their removal guidelines. If I had more to test I would try lower torques, maybe 15 ft-lbs, at least in good granite.

J. Albers · · Colorado · Joined Jul 2008 · Points: 1,926
Greg Barnes wrote:I was unable to remove a Legacy bolt from granite, and another was barely removed during testing in hard sandstone. Anyone who intends to use them for an area should first get 10 of them to test removal method in your local stone. I'd strongly recommend that you torque to no more than the minimum mentioned torque with the Legacy bolt, the bolts seem to stretch easily. I see they've changed it from a torque range to a guide torque of 20 ft-lbs, but that's what I used in granite and was unable to remove using their removal guidelines. If I had more to test I would try lower torques, maybe 15 ft-lbs, at least in good granite.
Hmmm. That's a bummer Greg given that the premium price was supposedly because of ease of removal.
Micah Klesick · · Charlotte, NC · Joined Aug 2013 · Points: 3,971

I agree that the Cobra seems pretty substandard in the strength department.
It's too bad so many developers are willing to use sub-par bolts to save a few bucks... If people really want to save money, but use stainless, you can get SS 3/8" x 3.75" Power-Stud wedge bolts for just over $1 each, the same price as a plated Cobra bolt and it will last much, much longer, and is stronger...

Monomaniac · · Morrison, CO · Joined Oct 2006 · Points: 17,295
Micah Klesick wrote: you can get SS 3/8" x 3.75" Power-Stud wedge bolts for just over $1 each, the same price as a plated Cobra or Powers bolt... and it will last much, much longer, and is stronger...
According to Powers, the 3/8" Power-Stud is significantly weaker than the 3/8" Power-Bolt:

powers.com/pdfs/mechanical/…

For 4000 PSI Normal Weight Concrete:
3/8" x 3.5" Power-Bolt: Ult. Tension: 27.0 kN Ult. Shear: 38.9 kN
3/8" x 3"*,** SS Power-Stud: Ult Tension: 18.7 kN, Ult. Shear: 16.9 kN

Perhaps you were referring to a different wedge bolt? If so, please post a link. The Powers "Domestic Wedge Anchor" looks to be a bit stronger than the Power-Stud in 4000psi concrete, but still much weaker than the Power-Bolt, frighteningly so (14.3 kN**) in tension in 2000psi conrete, which is comparable to soft rocks like volcanic stone and some sandstone:

powers.com/pdfs/mechanical/…

Unfortunately it seems to me that wedge bolts are doomed to be weaker than Power-Bolts at any given diameter due to the threaded shaft. I've yet to find a 3/8" diameter wedge bolt that meets the UIAA standard**, but I'd love to be proven wrong.

(*3" is the longest 3/8" Power-Stud for which Powers provides data)
(**the UIAA standard is 20 kN "axial load bearing capacity", aka tension, and 25 kN shear)
Micah Klesick · · Charlotte, NC · Joined Aug 2013 · Points: 3,971

Correct. Stud's are always going to be weaker than the comparable Powers 5-pieces, however in the rock we have around here (very hard basalt) they are more than adequate (4,200lb pull/3,760lb shear). I would never use wedge bolts for sandstone, or tuff, such as at Smith Rocks. There I would only use 5-piece bolts, or glue-ins. But in the basalt we have around here, they work well. I was looking it up a while back, supposedly the basalt here in the area runs between 12,000 and 20,000 psi, so it is quite hard, on par with good granite.
I don't like wedges much due to being hard to replace, but a SS wedge is going to outlast 5 generations of non stainless bolts, in the wet weather we have here, which is a fair trade off. We have routes up here in the Portland area that have had 5-6 rebolts in 25 years from climbers using non-stainless bolts, however, I pulled a stainless bolt out the other day just that was supposedly 12-15 years old just to see how it looked, and it didn't have a spec of rust on it.
I understand cost issue when you have a type of rock that you can't use wedge bolts in, but glue in Climb Tech bolts are only $6 each, and when you consider you don't need a hanger, the price isn't that bad...

mattm · · TX · Joined Jun 2006 · Points: 1,885
Monomaniac wrote: Unfortunately it seems to me that wedge bolts are doomed to be weaker than Power-Bolts at any given diameter due to the threaded shaft. I've yet to find a 3/8" diameter wedge bolt that meets the UIAA standard**, but I'd love to be proven wrong. (*3" is the longest 3/8" Power-Stud for which Powers provides data) (**the UIAA standard is 20 kN "axial load bearing capacity", aka tension, and 25 kN shear)
Hilti KB3s meet UIAA specs and are my favorite stud by far. The clip is much better than other designs and has more consistent lock up with fewer turns in my experience (Hard Limestone).

Also available in both 304 and 316.

3/8 x 3 3/4" 304SS ~ $2.75ea

ebay will also occasionally have them.

3/8" KB3 specs
Monomaniac · · Morrison, CO · Joined Oct 2006 · Points: 17,295
Micah Klesick wrote:...in the rock we have around here (very hard basalt) they are more than adequate (4,200lb pull/3,760lb shear)...
I'm not so sure. 3,760 lb is 16.7kN. The UIAA standard is 25 kN for shear. I agree rock strength is a big factor in pull-out strength but not so much for shear.
Monomaniac · · Morrison, CO · Joined Oct 2006 · Points: 17,295
mattm wrote: Hilti KB3s meet UIAA specs and are my favorite stud by far. The clip is much better than other designs and has more consistent lock up with fewer turns in my experience (Hard Limestone). Also available in both 304 and 316. 3/8 x 3 3/4" 304SS ~ $2.75ea ebay will also occasionally have them.
Wow, those are quite strong for a 3/8" diameter wedge bolt. Still not as strong as a power bolt in shear at 3000psi and above, but they meet the UIAA standard. Where are you getting that price? The best I can find is $4.12 from Climbtech.
J. Albers · · Colorado · Joined Jul 2008 · Points: 1,926
Monomaniac wrote: I'm not so sure. 3,760 lb is 16.7kN. The UIAA standard is 25 kN for shear. I agree rock strength is a big factor in pull-out strength but not so much for shear.
Mono, do you not like the KB3 for some reason other than the stud sticking out a little bit? Because as Matt notes above, they certainly meet UIAA standards, they set super easy (I've never had one spin on me...though I am diligent about cleaning my holes), and even the SS rigs are pretty cheap. Moreover as I think someone pointed out, they don't stick out nearly as bad as some other, perhaps older, models of studs.

EDIT: Your post above went up while I was posting....so you pretty much answered my question.
To answer your question about price, I am not sure where Matt is getting them, but the friend that I always bought from gave them to me for ~$2.50/bolt, so that kind of deal must exist somewhere (though he bought by the thousand). But even rapbolting.com has them for $3.29/bolt if you buy a box of 50.
Monomaniac · · Morrison, CO · Joined Oct 2006 · Points: 17,295

That first post, quoting Micah, was referring to his recommendation of the Powers "Power-Stud".

Brian in SLC · · Sandy, Utah · Joined Oct 2003 · Points: 21,711

I'll ditto the KBIII's as nice studs. I place them as the first three off the ground, and, at cruxes and anchors.

Have to admit I use a stock of Powers studs in the in between where the fall factor is lower.

A gob of KBIII's showed up on eBay awhile back for super cheap. I stocked up. My favorite bolt/stud for sure. Never fail to set and they snug up very predictably.

Joseph Crotty · · Carbondale, CO · Joined Nov 2002 · Points: 1,903

In general with regards to the quality of bolt installs I believe knowledge, experience and execution especially with respect to detail are critical. Whether it's an adhesive or mechanical bolt installs can be botched in a plethora of ways.

Although I have not pulled as many mechanical bolts as GreggerMan I have done my share in both Eldo and Clear Creek. Some of the constants that we see when replacing mechanical bolts:

  • Torque wrenches are not used 100% of time. Under/over torquing happens.
  • Mechanical bolts become loose over time and need tightening every few years more so on overhung routes.
  • Inadequate hole cleaning can lead to spinners or less then ideal installs.
  • SS threads can stretch and become damaged on install.
  • Mixed metal installs happen more frequently then the casual observer would assume leading to rust acceleration (i.e., galvanic).
  • Bizarre install ideas; plumbers putty, caulk, insert odd goop like material here placed w/ bolt in the hope it will keep water out.
  • Hardware store bolts are still rarely being installed.

Having also placed glue ins they have their pros and cons. The upside being greater chemical resistance (i.e., rust), holding power, increased life span, stress free and lower visibility. The downside is price, cure time and lack of original hole reuse.
mattm · · TX · Joined Jun 2006 · Points: 1,885
Joseph Crotty wrote:Having also placed glue ins they have their pros and cons. The upside being greater chemical resistance (i.e., rust), holding power, increased life span, stress free and lower visibility. The downside is price, cure time and lack of original hole reuse.
Honestly, the only real downside to Glue Ins is the extra work, both placing and, eventually, replacing.

Price - Wave's in 304SS are $6.25
Bolt Products equivalent in 316SS are $3.50 (shipping is the challenge right now... group buy anyone? I've heard of people bringing Jim's stuff back in suitcases!)

Cure Time - Can be 30min with certain glues. By the time I finishing cleaning up a newly-bolted route it's ready to climb.

Hole Reuse - Won't be needed that often but can be cored out if needed (agreed it's a PITA)
Kevin Rogers · · Salt Lake City · Joined Jun 2012 · Points: 11

First, The new Powers PB+ 3/8” diameter bolts should not be used for climbing.

Period.

Sadly, the folks at Powers do not see climbers as a strong enough financial demographic to leave the design alone. But it is what it is. There is no sense in lamenting them. Thankfully, there are other options.

Second, I use the the plated Cobra 1/2" bolts frequently (3.5”) in arid environments and find them to be more than adequate. I just want to point out that 1/2 Cobra bolts (which are plenty strong) are still substantially less expensive than any of the 3/8” hardware by most of the companies listed in this thread.

Also, for the sake of argument, I have on occasion purchased higher grade unthreaded shaft, replacement bolts that are compatible with the Cobra sleeve mechanism and expansion cone. I keep them in my bolt kit and I will switch them out on any anchor that has the potential to bear repeated high fall factor stress. Between the higher grade steel, and the solid shaft, this boosts the shear strength another 25% (conservatively). My point in all of this is that all Cobra anchors should not be getting a bad rap in this thread. Even if I purchase new core bolts, use just the Cobra expansion mechanism, they are still less than 1/2 the price of the new PB 1/2” bolts, and every bit as good. I imagine the same could be done with their 3/8” diameter bolts if the threaded shaft gives you headaches.

Bottom line, overly expensive hardware means less climbers that can afford to engage in bolt replacement efforts. All bolts fail eventually. I for one do not want to rely on the 1% of folks who can afford an endless string of $15 SS or glue-in anchors to do all the route maintenance.

And yes, it is always sad when people get hurt climbing. But it needs to be clear, as callous as it may sound, that the climber is responsible for the evaluation and technique he/she is willing to use (or not use) on any given set of anchors. While using plated hardware in the NW, NE, or other humid/oceanic environments may be negligent, it most certainly is not the case in arid environments. I grow weary of those who perpetuate this idea, going beyond even the UIAA (who certifies millions of plated anchors every year) by insinuating we all need to step in line with this concept.

Route developers rarely make money, nor are they building an amusement park. If they were, they would charge an entrance fee and a good portion of that fee would go toward the inspection and replacement of the hardware which they would then be liable for. But too often climbers are quick to balk at entrance fees and even quicker to put on trial the guys who came before them for not meeting their better than UIAA “standard" when providing the very entertainment that they DID NOT PAY FOR.

We would all be better off if more climbers took the time to educate themselves, invested in a drill and a bunch their favorite flavor of approved hardware, went to their favorite crag with rusted out manky anchors and took the time to REPLACE THEM themselves instead of lambasting the guy who put them in 25 years ago.

DrRockso RRG · · Red River Gorge, KY · Joined Sep 2013 · Points: 815

Thanks to a community funded fixed gear initiative in Red River Gorge (humid environment) nearly all developers bolting new routes on public land are now using SS powerbolts or glue ins. The model is that developers pay the equivalent of a carbon steel PB and the community fund makes up the difference to buy the SS equivalent. Because we are placing bulk orders together we can get the hardware cheaper than buying them individually. Some of the funds from the Iniative also go towards rebolting efforts using glue-ins. The iniative should greatly reduces the burden on future rebolting needs. Perhaps this model could work for other areas?

Thomas Beck · · Las Vegas, Nevada · Joined Feb 2006 · Points: 1,025
" I use the the plated Cobra 1/2" bolts frequently (3.5”) in arid environments and find them to be more than adequate. I just want to point out that 1/2 Cobra bolts (which are plenty strong) are still substantially less expensive than any of the 3/8” hardware by most of the companies listed in this thread."
-----------------------------
Kevin, I assume you are bolting somewhere around SLC? I'd be interested in some anecdotal results regarding aging on the hardware you placed which is now 10 years old or older. I'd like some feedback on any problems unique to placing Cobras. For instance do the threads clog during installation? I may have placed around 300 to 400 Rawl bolts and know how they feel during tightening. Are the Cobras any different in your experience?

For myself I am placing in limestone, quart monzonite, basalt and Red Rocks sandstone. I have pulled a couple bolts which were 10 years old or older. Even in limestone in this climate, if the area receives little water run off, after 10 years there is very minimal pitting.

3/8" Rawl Bolt placed over 10 years ago in granite at Keyhole Canyon, NV

Apologies for the thread drift. I understand about the need for stainless and try to bolt responsibly. I thought I was going to get the last of the local Fasco Powers plated stock yesterday but there was some misunderstanding and Fasco is out of the old style Powers bolts. I am looking on the internet but with little hope.

It seems for my use I am either buying the plated 1/2" Cobra bolts or buying the new version 1/2" Power Bolt+. I am interested in what length Cobra bolts you are using and in what rock or conditions. I am especially interested in your experiences if you are developing around the Cottonwood Canyon areas. I have a multi-pitch line I want to do in California in an environment similar to LCC and wonder about whether I should use stainless for all of it or part of it.
Guideline #1: Don't be a jerk.

Fixed Hardware: Bolts & Anchors
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