Loose nuts on bolts

So I've come across plenty of loose nuts on bolts for anchors or sport climbs. I was thinking about throwing a small wrench in with my cragging gear so I could tighten them more than hand tight. Is this a good idea? How tight should I make them? I know you don't want to overtighten so should I just snug them up?

Chris Plesko wrote:So I've come across plenty of loose nuts on bolts for anchors or sport climbs. I was thinking about throwing a small wrench in with my cragging gear so I could tighten them more than hand tight. Is this a good idea? How tight should I make them? I know you don't want to overtighten so should I just snug them up?

Just snug them up. With a small wrench, and your hand close to the bolt, you should be fine as long as you don't crank on it so that it hurts.

You can also get them fairly tight w/ a Leatherman type multi-tool, which has the added benefit of being a little more useful in your pack. Just don't strip the bolt :)

The one downside to the Leatherman is you can't really tighten on lead, but you can w/ a wrench if it is easily accessible.

I know that with a handle like buttonheadspinner I might not have credibility on this question!

It seems to me that new technology bolts (roughly 15 years old or newer) should not become loose and if they do it would indicate that the integrity of the bolt is in question. New bolts rely on torque on the nut pulling a cone into a sleeve (or similar) and the resultant outward pressure of the sleeve against the wall of the hole. Without the torque wouldn't the bolts resistance to pulling out be significantly reduced (or at least I would assume this would be the case)? I'd not heard of a lot of newer bolts with loose nuts. I think it would be a question for the manufactures. Old contraction bolts with loose nuts, yes but new expansion bolts, no.

Whatever you do, be careful(!!!111!!!), I saw (actually, heard, we were around the corner) a guy at Smith Rocks deck from 40'ish when the bolt he was tightening with a wrench broke and his g/f who had him on a friction device couldn't really stop the fall...she managed to slow him down enough not to completely mess him up and had horrendous burns on her hands to show for it. It was a pretty grim scene overall and I think he fractured/broke some bones.

So I guess the "safer way" may be to tighten on tr or descent.

I think spragues advice is pretty on target, the old "finger tighten" just doesn't get the job done very often...

I'm not too worried about tightening on lead at this point. If a loose bolt can be properly tightened by me in the field then I'm willing to do it when rapping, lowering, on TR or whatever is appropriate. I just feel like when I finger tighten a nut it isn't really doing any good.

To address the concern of Buttonheadspinner, SS bolts often have issues with loosening a bit in the first season they are placed. Usually these are wedge bolts, where the nut comes loose and the hanger moves slightly. This is in no way an indication of the quality of the bolt placement, generally the wedge is firmly seated and only the entire nut coming off the bolt would cause any sort of problem.

5 piece bolts are different, and the hex head of the bolt is directly engaged into the wedge. These bolts should generally not be tightened unless you have a lot of experience because they may be fully seated and further tightening could cause metal fatigue or bolt failure.

If you want to tighten down wedge bolts bring some loc-tite with you to prevent them from coming loose in the future. Tighten them finger tight plus 1/4 turn with a wrench. Your goal is only to tighten them so that the hanger does not spin, and that is all.

Just remember, a modern bolt with a spinning hanger still is incredibly strong. An overtightened bolt on the other hand could fail with body weight. So if you are uncertain about the type of bolt it is best to leave it alone.

i keep a crescent wrench in my crag pack and just tighten them enough to where i can't spin it with my hand. Every bolt construction and placement is different and I don't know enough to understand what to do so this is my rule of thumb. I generally tighten on lowering/cleaning and I never mess with anchors

Happy climbing!

I think nuts on wedge bolts naturally loosen due to thermal expansion and contraction. The initial placement is what sets the bolt in the rock via the proper torque; so just snugging up the nut is an act of maintenance. I like combination box and open wrenches, I think 1/2" for a 3/8" bolt and 9/16ths for a 1/2" (don't hold me to those sizes) are best, you thread through the box end to clip them on something.
If while you're tightening the nut back on you realize its a spinner, then that would a good bolt not to fall on; no different than a rattly piece of gear.

Hey folks,

It's interesting how certain technologies are available in one area but completely unheard of in another. Here's a perfect example of where such technology transfer hasn't taken place.

The issue with any bolts is not knowing whether they're sufficiently tight. Simply cranking on them may actually do more harm than good; Over-tightened bolts can be just as bad as (or worse than) undertightened bolts.

There's a type of bolt in which you can easily tell how tight it is just by noting its colour. If it's YELLOW, it's loose. If it's GRASS GREEN, it's at the correct tension. If it's DARK GREEN, it's too tight.

If you see a bolt that's YELLOW, tighten it with whatever you've got handy until it turns GRASS GREEN again. As they say: No muss, no fuss and, no failed anchors ;-)

Cool, huh?

Hevii Guy wrote:Cool, huh?

Sounds (guardedly) cool.

Seems to require a special order? Minimum number perhaps?

smartbolts.com/products/hr-…
smartbolts.com/products/dti…

[edit]

mcmaster.com/#catalog/116/3…

"Screws are made from alloy steel and have a zinc yellow-chromate plating for added rust resistance. They have a Class 2A thread fit and a minimum Rockwell hardness of C33.

Although not rated for strength, these screws have not less than 85% the tensile strength of equivalent size Grade 8 hex head cap screws."

Available in 1/2", 5/8", 3/4" diameters. Prices start at more than $19.00 for the screw only. I see a few problems here.

Larry wrote: Sounds (guardedly) cool. Seems to require a special order? Minimum number perhaps?

They're too big, and, they're 20 bucks per.

You'd have to drop them into a Powerbolt type placement. 1/2" Powerbolts take a 3/8" threaded bolt.

Made out of some alloy steel? Might be a problem too.

Be cheaper to just buy a torque wrench.

Mike Lane wrote:I think nuts on wedge bolts naturally loosen due to thermal expansion and contraction.

Hmmm...probably not that much of an effect, compared to other issues. Thermal changes would happen to both the nut and the stud, and, they're both the same materials usually, so, would be the same.

I think what happens usually is a number of things. Surface prep, and, a hanger that doesn't seat exactly flat on a surface is an issue (very hard to do in the field). Also, a slight load on a hanger may be enough to move it slightly, which will loosen the nut. Most hangers aren't placed with their orientation to take a load without some bending or moving. Also hard to do during installation. You can kinda guess by weighing a hanger with a draw before you tighten the hanger down, but, sometimes the load angle changes if someone falls at different positions relative to the placement.

I think, especially for stud/nut type wedge anchors, folks probably usually under torque them, so, they start out by being a tad loose. Best to get a feel with a torque wrench and to know what the installation torque really is.

Rock breaks, even small crystals. If the hanger is seated on one little crystal that's loose, or, becomes loose, then, eventually they'll be movement if there's any load on the hanger.

Surface prep during bolt/hanger installation of the area where the hanger seats is something I'll bet not many folks pay attention to. I've tried to reduce any levering in wobbly installations (uneven rock) by putting JB weld or some putty under the hanger to get it to seat flush. Works well. But, its a pain to use.

I'm not a fan of folks using loc-tite. If you get a loose hanger, and, the nut is loc-tited, then it might be pretty difficult to ever get the placement snug again. I worry about folks having to overtorque the bolt to break the loc-tite loose too. Also, using any lubricant on threads will change the installation torque. Too much loc-tite will also be a problem trapping moisture in the hole too, and, could really accelerate corrosion in the bolt hole.

Some things to keep in mind.

"torque" them and we'll be safe ????

Bad, bad (very bad) idea.

"Torque" often has absolutely NOTHING to do with how tight a bolt is! It's only a measurement of the resistance to input force as you're trying to turn a nut. Relying on "torque" results in a very dangerous false sense of security.

Consider this:

If the threads have become dinged or dirt got into the threads or the nut is otherwise seized, you can apply the "proper" (hah!) torque and the fastener would still be loose!

The only true indication of a bolt's load is its elongation. This is why on critical industrial applications, a fastener's elongation is measured after a "target" torque has been applied. If the applied torque did not produce sufficient load, more torque is applied accordingly. Thus, the fastener is "tuned" to ensure that it's properly tightened.

Change in elongation is what causes the colour of these bolts to change.

Yup, they're expensive. But, so are helmets, seatbelts, parachutes, liferafts, airbags etc...

Hevii Guy wrote:"Torque" often has absolutely NOTHING to do with how tight a bolt is! It's only a measurement of the resistance to input force as you're trying to turn a nut. Relying on "torque" results in a very dangerous false sense of security.

Poppycock.

how about disc springs ? turn the wrench till they're squashed flat, and you're done! At 87 cents each they won't break the bank, and will maintain some tension to help stop the nut from coming loose.

I carry a small adjustable wrench in my pack for this purpose. Sometimes I will also carry a few hangers in case a manky one needs replacing. Make sure you are familiar with the bolts that you are tightening down.

One of the biggest issues that I've found with wedge bolts loosening up is that the hangers get rotated counterclockwise, causing the nut to loosen up in the process. To prevent this during a new bolt installation or while tightening up an existing one, it's best to slightly pre-rotate any hangers that may take this kind of load counterclockwise. Oftentimes these are the first bolts of a sport route (taking a multi-directional load) or one that gets pulled hard to the right while someone is lowering or top roping. Another issue with newer placements is that the rock behind the hanger will wear with anchor use, increasing the space between the hanger and the rock and subsequently loosening the hanger. With wedge bolts, the nut can simply be tightened down. A smart bolter will even out the the rock first, using hammer or whatever, to smooth out the surface. This is especially true with coarse/grainy rock like granite, and can be done by simply rubbing the rock with the hammer in most cases. Be careful with loc-tite, because if the nut loosens after using this stuff it will be very hard to tighten down. Now with loc-tite on the bolt it will need a lot of torque, and too much torque on the nut can potentially weaken the bolt, or even cause the whole anchor to loosen and rotate around in the hole.

It's not a good idea to tighten any bolt while hanging from it. Do it while it's unloaded!

Brian in SLC wrote: Poppycock.

Poppycock? Poppycock?!!

That's like claiming the earth is flat. What's so difficult to grasp about the statement that "torque" is an unreliable indicator of a bolt's tightness?

How about this: Bash just one or two threads on all of your wheel studs. Do this at a couple of thread lengths down from the end. Put your wheels back on. "Torque" the nuts to the same torque that you've always tightened them to. Just to make it interesting, use a "calibrated" torque wrench.

When the wheels fall off as you hurtle down the highway, you can claim ignorance because, after all, you properly applied the right torque!

Hevii Guy wrote:How about this: Bash just one or two threads on all of your wheel studs.

How 'bout this: try posting on a topic you actually know something about.

Hevii Guy wrote: Poppycock. Poppycock? Poppycock?!! That's like claiming the earth is flat. What's so difficult to grasp about the statement that "torque" is an unreliable indicator of a bolt's tightness? How about this: Bash just one or two threads on all of your wheel studs. Do this at a couple of thread lengths down from the end. Put your wheels back on. "Torque" the nuts to the same torque that you've always tightened them to. Just to make it interesting, use a "calibrated" torque wrench. When the wheels fall off as you hurtle down the highway, you can claim ignorance because, after all, you properly applied the right torque!

It is true, relying on torque alone is not perfect.

We tighten the tension rods on hydraulic cylinders (450kN) by indirectly measuring the rod's elongation; in practice, this comes down to turning the nuts by a specified number of turns, since we know the pitch of the threads.

For brand-new bolts and nuts, relying on torque might be good enough, if the manufacturer provided one, or if you calibrated your torque the first time using elongation.

But if the frictional properties of those threads change over time, re-torquing that loose nut later could be inaccurate... someone would have to run a controlled weathering test to see if that is a true problem in reality...maybe that HardIsEasy guy on YouTube would jump at this project

For what its worth @Brian in SLC, I agreed with your first comment, it had a lot of good points.

Please get a torque wrench so you know you're going to tighten the bolts to the proper torque.  You can find cheap adjustable torque wrenches, and all you'll need is a 1/2" and 9/16" socket to cover every bolt you'll find in the Front Range.  If you're unsure of how to do this, you can report the hardware to the BCC.  If you'd like to learn everything you need to know about bolt replacement and get out and replace bolts, they'll teach you for free.

https://www.boulderclimbers.org/bolt-replacement