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Seriously? Do you need a torque wrench for bolts?
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By Crag Dweller
From New York, NY
Jul 23, 2012
My navigator keeps me from getting lost
Dan Brayack wrote:
...I've placed maybe 400 bolt or so and every one of them, I've just tightened them as tight as I could... -Danno


that's a little scary.

edit: having read your later posts, i'd say it's a lot scary. please let us know where you've put routes in so we know what areas to avoid.

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By Crag Dweller
From New York, NY
Jul 24, 2012
My navigator keeps me from getting lost
Dan Brayack wrote:
...none of my bolts are going to fail...


None of them? Not even the one that did pull out?

Bolt Failure Accident at New River Gorge
Bolt Failure Accident at New River Gorge

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By Dan Brayack
From Marmet, WV
Jul 24, 2012
Coopers Rock, WV
If you read the article, you'll see that that bolt wasn't even tightened down and was on a closed project.

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By Morgan Patterson
Administrator
Jul 24, 2012
Stoked...
Dan Brayack wrote:
If you read the article, you'll see that that bolt wasn't even tightened down and was on a closed project.


So Dan, what areas specifically have you been bolting? If there's nothing wrong with what you are doing you should have no issue responding with details.

Somehow you seem to be ignoring this question posed to you by many people on the thread... Are you too much of a coward to actually respond or are you afraid you'll be held responsible if something happens to someone or are you just making this thread up?

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By Crag Dweller
From New York, NY
Jul 24, 2012
My navigator keeps me from getting lost
Dan Brayack wrote:
If you read the article, you'll see that that bolt wasn't even tightened down and was on a closed project.


I did read the article. I also read the accident report on the Appalachian Mountain Institute's web site: appalachianmountaininstitute.c...

An interesting excerpt:

"The excessive marks on the bolt, hanger and nut, plus the threads not working may have been an indication that the bolt had too much resistance while being driven into the rock. The damaged threads appeared to have caused the nut to lock down before the collar on the wedge was fully engaged. It appears as though the collars were, however, partially engaged, which might have added to the illusion that the bolts were solid.

There are several additional questions that need to be analyzed. The first of those should address the bolt installation. Was there added resistance with the bolt’s installation? If this is true, how old was the drill bit and was the bit’s diameter still acceptable enough to drill a quality hole? Was the bolt simply hammered too hard or too irregularly? What damaged the threads?"

Elsewhere in the report it describes damage to other bolts on the route.

The point is that someone has been injured as a result of your bolting practices. And, yet, you have the hubris to hop online and spray about how you knowingly disregard the recommended specs and brag about how none of your bolts are ever going to fail.

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By Rick Mix
From Nederland, Colorado
Jul 24, 2012
My 2cents:
Being able to afford a drill has never qualified anyone to use one.
Bolts come with spec sheets in every box. I've known only a few who actually use a torque wrench. I use the "watch the tendon on my wrist" method. Takes years of practice though. 2.5-3.5 turns past finger tight is the spec for not using a torque wrench.

Good thread so far, though things seem to be be heating up for some. Let's keep it easy folks.

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By John Wilder
From Las Vegas, NV
Jul 24, 2012
It seems to me that torquing blindly is foolish- lives are being trusted to the bolts people install and they should at least spend a bit of time learning what proper torque on a given bolt feels like.

I used a torque wrench for awhile, and am always VERY careful on 3/8" SS bolts, as I have snapped one or two, as have many of my friends, while tightening them. I even snapped a 1/2" carbon bolt once while tightening it with a torque wrench- it snapped just below its recommended torque.

at any rate, Dan, you know your area better than I, but if the New is as hard/solid rock as i've heard, over-torquing your bolts there could be pretty dangerous- the one bolt I broke torquing to spec was in the hardest rock i've ever drilled in red rock, felt like granite.

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By dnoB ekiM
Aug 12, 2012
Wonderstuff
John Wilder wrote:
It seems to me that torquing blindly is foolish- lives are being trusted to the bolts people install and they should at least spend a bit of time learning what proper torque on a given bolt feels like. I used a torque wrench for awhile, and am always VERY careful on 3/8" SS bolts, as I have snapped one or two, as have many of my friends, while tightening them. I even snapped a 1/2" carbon bolt once while tightening it with a torque wrench- it snapped just below its recommended torque. at any rate, Dan, you know your area better than I, but if the New is as hard/solid rock as i've heard, over-torquing your bolts there could be pretty dangerous- the one bolt I broke torquing to spec was in the hardest rock i've ever drilled in red rock, felt like granite.


Wow! You guys must have really big wrenches or are MUCH stronger than I!

I bought a torque wrench long ago to figure out what 20ftlbs feels like because I am anal about such things...but this thread got me to thinking.

So, I thought I would over-torque some bolts. I tested a Fixe 10mm carbon wedge and a few Hilti Stainless 3/8" wedges. I started out by tightening to "feel" with my regular wrench and then tested that with a torque wrench. Each time it came in a tad under 20ftlbs.

I tightened the Fixe to 40lbs without issue and pounded it out (I had it in a cobble.)

I then tried a Hilti and did the "feel" test to right near 20lbs and then tightened it with the torque wrench to 40lbs which broke the cobble...see pic1.

I tried another Hilti with the same results...see pic2.

I then dropped a Hilti into some concrete outside and "feel" tightened to right at 20lbs and then tighted it to about 55lbs with my torque wrench where there was a noticable "slip" (I think this was the stainless actually turning internally; "bending" if you will; or maybe it is the bolt rotating in the hole while the wedge stays still?; is this the "pop" Dan describe's above..that's a scary thought! These are wedges too.). I then stopped and felt the bolt and it was HOT to the touch. I reattached the torque wrench and the bolt "slipped" a couple of more times as I tightened it all the way up to 70lbs where it sheered off (see pic3). The bolt was VERY HOT at this point...see pic 3. Sorry its blurry...but it is a sheared stud with the nut virtually welded on.

Recommended max torque on the Hilti is 20lbs.

I recommend everyone tightening bolts learn the "feel" on a torque wrench...but man am I amazed you guys are shearing bolts with a small wrench. You must be wailing on them! Lighten up, these are expansion bolts...not your truck's lug nuts (which are torqued at 80lbs).

Dan's "tight as I could" is certainly too tight for most bolts...but I am amazed that people are applying over 40lbs with a small wrench. Of course...it's not the sheared bolts you have to worry about...it's the ALMOST sheared ones.

Regarding the NRG bolt-failure noted above...these bolts did not shear..they pulled and had some thread damage and the like. Did anyone determine if they were 10MM bolts pounded into a 3/8" (9.5mm) hole? That could damage the cone, wedge and threads.

Pic1-Hilti Stainless to 40LBs.
Pic1-Hilti Stainless to 40LBs.


Pic2-Hilti SS to 40lbs
Pic2-Hilti SS to 40lbs


Pic3-Hilti SS to 70ftlbs
Pic3-Hilti SS to 70ftlbs


Broken cobble from 40lbs torque
Broken cobble from 40lbs torque

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By coop
From Glenwood Springs, CO
Aug 13, 2012
Indian Creek Climbing
What is your favorite torque wrench?

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By dnoB ekiM
Aug 13, 2012
Wonderstuff
coop wrote:
What is your favorite torque wrench?


I just use this standard needle wrench: amazon.com/Neiko-Classic-Needl...

It's certainly not the nicest one made, but it does the trick. And at less than $20 there is no excuse not to get one.

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By slim
Administrator
Aug 13, 2012
tomato, tomotto, kill mike amato.
breaking wedge bolts (or similar) isn't as common as snapping the powers style bolts.

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By Old and Busted
From Centennial, CO
Aug 13, 2012
Stabby
slim wrote:
breaking wedge bolts (or similar) isn't as common as snapping the powers style bolts.

Yeah, and I hate how you just can't tell whats under the head of that cap bolt.

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By socorroscott
From socorro, nm
Aug 13, 2012
I use a beam style (needle) torque wrench. They are lighter, and cheaper than the click stlye. I find the click style hard hard to hear when it is windy on the wall. Also, I am of the opinion that bouncing a click style around during a rough approach could easily uncalibrate the internal clutch.

As for not using a torque wrench at all...wtf? That is like going for the dickstab without having the fartbox.

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By Rick Mix
From Nederland, Colorado
Aug 13, 2012
I don't know any mechanic that would use a needle wrench. Famously inaccurate.

Click wrenches have "feel" and don't require the user to hear anything. You'd have to bang one around quite a bit to foul the adjustment.

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By Jim Titt
From Germany
Aug 13, 2012
I´ve tested loads of stainless wedge bolts (probably several hundered by now), I´ve even an article on it somewhere.
For a M10 wedge bolt ultimate failure is at 117Nm/86ft.lbs and the usual overtorquing failure is at 92Nm/68ft.lbs when the small tabs on the clip shear off (this is when the bolt goes `soft´and starts to spin. This is designed in by the manufacturers so you can´t break or weaken the bolt by overtorquing at least according to our manufacturer who should know.
Typically these torque numbers are impossible with a normal spanner.
The actual strength of the bolt when tested is virtually the same no matter the torque applied (including zero) until you break the tabs on the clip where the pull-out resistance drops but only marginally, still 38kN so plenty strong enough.
For multi-piece bolts we have no data as we never use them.

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By Vaughne
Aug 13, 2012
Dan, I think it's great that you have been honest and upfront about this. After reading this whole thread (which is FANTASTIC btw) it appears that your bolts are maybe ok, but maybe not! There is just no way to be sure based on what you have told us. Although I understand that you think your bolts are fine, I firmly believe that you owe it to the climbing community to provide a list of climbs or at least crags that you have bolted. Perhaps one of the several qualified contributors to this thread would even be willing to test one of your bolts in the field. Sometimes you have to man up and choke down your pride a little in order to maintain your self respect (and the respect of others).

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By 20 kN
From Hawaii
Aug 14, 2012
Jim Titt wrote:
Typically these torque numbers are impossible with a normal spanner. The actual strength of the bolt when tested is virtually the same no matter the torque applied (including zero) until you break the tabs on the clip where the pull-out resistance drops but only marginally, still 38kN so plenty strong enough. For multi-piece bolts we have no data as we never use them.

You have 10mm threaded wedge bolts that hold 38kN? Are they made out of grade eight stock? Thirty eight kilonewtons is pretty strong for a 10mm wedge. That is stronger than any 3/8" wedge bolt out there, as far as I know.

As far as torque goes, I believe it is pretty easy to get a lot of torque applied to a bolt. I have never tested a standard box wrench, but I can generate something like 200 ft/ lbs with a 1/2" x 22" spanner. When I used to work as a welder, I would assemble large trailers with huge 1"+ grade eight bolts. I would tighten them with a 3/4" pneumatic impact driver rated for something like 800 ft/lbs. Afterwards, I would use a 3/4" x 24" spanner to tighten them further. The fact that I was able to turn the bolt implies that I was able to apply in excess of 800 ft/ lbs of torque to the bolt. So I think it is completely possible to apply in excess of 100 ft/lbs with anything larger than a small run of the mill Wal-Mart box wrench.

As far as sleeved anchors, like the Power-Bolt, I can say it is completely possible to compromise the strength of the bolt by overtightening it. I do it all the time. I have had to remove hundreds of 3/8" SS Power-Bolts here in Hawaii. Because the cone is often fused to the machine bolt, I generally have to break the bolt by overtightning it in order to get the thing out. When I pull the bolt out, there are circular torsion stress marks that run along the length of the bolt that occurred by overtightning it. It appears that before the Power-Bolt will fail from overtightning, the bolt will spin around creating torsion stress, thereby reducing the strength of the bolt, but not causing failure until too many turns are generated.

Also, do you have a photo of the bolt you are referencing with the tabs that will break off? Are they like the tabs on the Hilti Kwik 3 bolt? I was always under the understanding that those tabs only exist to grab the rock so the expansion clip stays in place like it should.

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By Jim Titt
From Germany
Aug 14, 2012
An M10 stainless (316) wedge bolt usually holds 42-44kN but we rate them at 38kN as this is the lowest we have seen. That´s a pretty typical value from all the major companies in Europe.
There are also ones available which fail around the 10kN level, even ones made in Germany and that is the reason we test before we put them on the market, not everything that shines is gold!

With a standard 17mm spanner which is 190/200mm long or just under 8") I can pull 62Nm/46ftlb before the pain in my hand becomes too much and there is risk of injury.

If you can pull over 800ft/lbs with a 24" wrench then you should be in the Olympics since that means you applied over 400lbs on the end! Or of course it means you believe you achieved the rating on one of the most notoriously innacurate pieces of equipment ever made and used an air dump directly attatched to the tool instead of miles of flexible hose, my smaller air wrench is rated to 200Nm and I can stop it by hand if I use two hose extensions on it.
We tighten the head bolts on Volvo generators to 800Nm (590ft/lbs) and use a two metre torque wrench for the last bit!

The tabs engage in the rock so the clip stays still and doesn´t rotate while the cone pulls through and expands it, when the tabs are overloaded they either gouge through the rock if it is soft or the tabs fail in hard rock.


Failed tabs
Failed tabs


This is a bolt I cut out of the rock after it had failed, the tabs have distorted and gouged into the cone making the groove you can see which prevents the clip from properly sliding any further up the cone and makes the pull-out resistance lower. This one actually pulled a long way out and failed at the base of the cone when it bent at that point as it exited the hole (it was radially tested).

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By camhead
From Vandalia, Appalachia
Aug 14, 2012
You stay away from mah pig!
Vaughne wrote:
Although I understand that you think your bolts are fine, I firmly believe that you owe it to the climbing community to provide a list of climbs or at least crags that you have bolted.


Ok, there are a lot of valid issues in this thread, but to all the people that are going "tell us where you bolted!" it is pretty obvious that you are not and probably will not be climbing at the NRG anytime soon.

Dan is using his real name on this site, and the NRG guidebook gives first ascentionist info for every climb. It should be easy for any person in this thread to stay away from Dan's routes if they want to.

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By Old and Busted
From Centennial, CO
Aug 14, 2012
Stabby
If you want to climb only routes installed with a torque wrench you should not even bother coming to CO. And anyone who starts flinging that liability bullshit around needs a serious bitch slap.

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By Cor
Aug 14, 2012
black nasty
camhead +1
el tigre +1

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By 20 kN
From Hawaii
Aug 14, 2012
Jim Titt wrote:
An M10 stainless (316) wedge bolt usually holds 42-44kN but we rate them at 38kN as this is the lowest we have seen. That´s a pretty typical value from all the major companies in Europe. There are also ones available which fail around the 10kN level, even ones made in Germany and that is the reason we test before we put them on the market, not everything that shines is gold! With a standard 17mm spanner which is 190/200mm long or just under 8") I can pull 62Nm/46ftlb before the pain in my hand becomes too much and there is risk of injury. If you can pull over 800ft/lbs with a 24" wrench then you should be in the Olympics since that means you applied over 400lbs on the end! Or of course it means you believe you achieved the rating on one of the most notoriously innacurate pieces of equipment ever made and used an air dump directly attatched to the tool instead of miles of flexible hose, my smaller air wrench is rated to 200Nm and I can stop it by hand if I use two hose extensions on it. We tighten the head bolts on Volvo generators to 800Nm (590ft/lbs) and use a two metre torque wrench for the last bit! The tabs engage in the rock so the clip stays still and doesn´t rotate while the cone pulls through and expands it, when the tabs are overloaded they either gouge through the rock if it is soft or the tabs fail in hard rock. This is a bolt I cut out of the rock after it had failed, the tabs have distorted and gouged into the cone making the groove you can see which prevents the clip from properly sliding any further up the cone and makes the pull-out resistance lower. This one actually pulled a long way out and failed at the base of the cone when it bent at that point as it exited the hole (it was radially tested).

I should be in the Olympics? Nice, so are you saying you would sponsor me? Indeed, that doesent sound quite right, the wrench must have been longer. All I really remember is that I would use a 3/4" impact driver, then I would walk across the shop and pick up a massive 3/4" spanner that seemed to weigh over 35 lbs, and I was able to further tighten the bolt with the spanner. I have ran into the same thing with 1/2" impact drivers supposedly rated for something like 450 ft/lbs. I use them to put the lug nuts on my tires on, but then I would hit the nuts with a 1/2" torque wrench and I could get some of them to turn with 130 ft/ lbs or so. I have also been able to hold back a 3/8" impact driver by hand, so I am a bit weary about the specifications on some impact drivers.

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By Vaughne
Aug 14, 2012
camhead wrote:
Ok, there are a lot of valid issues in this thread, but to all the people that are going "tell us where you bolted!" it is pretty obvious that you are not and probably will not be climbing at the NRG anytime soon. Dan is using his real name on this site, and the NRG guidebook gives first ascentionist info for every climb. It should be easy for any person in this thread to stay away from Dan's routes if they want to.


You can't possibly know where I climb or where I may climb in the future. I travel all over and will likely visit the NRG someday. Thanks for providing the info on how to find the routes though.

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By Jake Jones
From Richmond, VA
Aug 14, 2012
Me and the offspring walking back to the car after a day of cragging.
I think what he means Vaughne is that there are thousands of routes in a relatively concentrated area. Putting the demand of listing developed routes on an FA that has developed multiple routes over a period of years, some likely done in chunks, is a bit unrealistic. For Dan to list these things, he would likely have to scour a resource to catch everything in detail, just as any of us would. I think what Camhead is proposing is much more viable, realistic, and easy on everyone involved- if you're going to be in the area and are truly worried about it.

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By Old and Busted
From Centennial, CO
Aug 14, 2012
Stabby
Vaughne- if you've climbed at Table, CCC, Shelf Rd., Penetente, Devils Head, BoCan., the Monastery; Rifel, Lime Creek, you have quite likely clipped bolts NOT set with a torque wrench. In fact, there is a good chance you haven't clipped one yet.

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