Spinners from Sideways Pull

Looking for suggestions to fix a habitually loosening bolt.

The route traverses in from the right, then goes vertical, creating a sharp bend in the rope line. Falls taken higher on the route cause the hanger at the change of direction to turn counter-clockwise, and loosen the nut.

It's a 3/8" stainless wedge bolt. Relatively new route that doesn't get a ton of traffic. A long sling helps some, but doesn't eliminate the situation.

Planning to re-torque, but wondering if there is any wisdom out there for further preventing this loosening. Metolius Spring Force Hanger? Loc-tite on the nut? Thanks in advance.

Use a nylock lock nut.  You can get one at hardware.  Before installing, run a bolt through it at home to cut threads in nylon, otherwise might spin the bolt in cliff.  They hold pretty well.  

Loctite

I Fwrote:

Loctite

Yep!  I think a lot of people who install SS wedge bolts missed this memo.  It really should be part of a standard installation.

The use of a nylon lock nut seems debatable if it’s a good idea.  Jim Titt seems to say no in this thread.

https://www.mountainproject.com/forum/topic/117526469/how-to-tell-if-a-bolt-is-safe

The mistake proof solution would be a notched glue in, maybe overkill but if it's a new route without a ton of traffic, and it's already happened more than once, it might be worth it.

Thanks all! The thread Mikey shared was informative. If I understand correctly, it sounds like the problem with a nylock nut is how it can make it difficult to get the correct amount of torque due to very different friction - kind of how a non-SS connection is less slippery than SS, so requires more torque create the correct tension.

Mikey (or anyone else), do you have thoughts on the blue vs the green (wicking) Loctite? If the Loctite reduces friction of the connection, is there risk of over torquing the bolt? If this is an issue, it sounds like the green Loctite could be a cleaver solution, as it's applied after the nut is torqued.

Jim - good point. I'm going to try to resolve it without having to remove the existing wedge bolt if possible. I'm guessing the bolts had never been re-torqued after they were placed, so I'm hopeful that torque and Loctice will do the trick.

The "slippery-ness" of the bolt on nut you are looking for is the k-factor. There may be tables out there with k-factors with blue loctite for the bolt you have but it should be pretty close for any bolt of the same material. 

I would vote blue or red loctite but honestly the most surefire way is a glue in imo.

In addition to the Loctite, you can build a very shallow pocket for the hanger to sit in so it won’t spin. Depending on the rock type/hardness, remove a very thin layer (1 mm ish) of rock where the hanger will sit in its proper orientation, in the upside down teardrop shape of the hanger.  This works very well for those rare hangers that tend to get pulled on sideways by hangdoggers. Works well on say sandstone, not so well on say granite. 

Mikey Schaeferwrote:

Yep!  I think a lot of people who install SS wedge bolts missed this memo.  It really should be part of a standard installation.

The use of a nylon lock nut seems debatable if it’s a good idea.  Jim Titt seems to say no in this thread.

https://www.mountainproject.com/forum/topic/117526469/how-to-tell-if-a-bolt-is-safe

Because any locking nut system/Loctite prevents a loose bolt from being tightened later.

Jim Tittwrote:

Because any locking nut system/Loctite prevents a loose bolt from being tightened later.

I've used nylocks for over a decade either professionally or for hobby projects. While the retentention is reduced after the first use they can definitely be retightened and reused. Not sure what you're getting at.

Nylocks are a really bad idea on wedge anchors. Installation will almost always cause the bolt to spin as you pass the nylon insert. In the rare event this doesn’t happen and the bolt reaches torque, the nut will be impossible to remove as the nylon insert will grab the threads enough to spin the bolt when an attempt to remove the nut is made. Some seismic building codes (California, Seattle, Anchorage) prohibit the use of nylock nuts on mechanical anchors for this reason.

Your best bet out side of the notched gluein is to take Kent’s advise on creating a small dish for the hanger. It would then be a good idea to install your choice of locking washer to help maintain torque on the bolt. I prefer stainless split washers but the “tooth” washers work fine too, just make sure the metals match.

With wedge bolts if the bolt is a spinner you cannot usually get the clip to engage to re-tighten them. You may succede if you carry enough tools to lever the whole assembly outwards to get initial engagement or not.

As noted above the European codes also prohibit their use as they can no longer be assessed or re-tensioned. Only double-nutting is permitted.

Zachary Winterswrote:

Looking for suggestions to fix a habitually loosening bolt.

The route traverses in from the right, then goes vertical, creating a sharp bend in the rope line. Falls taken higher on the route cause the hanger at the change of direction to turn counter-clockwise, and loosen the nut.

It's a 3/8" stainless wedge bolt. Relatively new route that doesn't get a ton of traffic. A long sling helps some, but doesn't eliminate the situation.

Planning to re-torque, but wondering if there is any wisdom out there for further preventing this loosening. Metolius Spring Force Hanger? Loc-tite on the nut? Thanks in advance.

Re the "spinner" are you talking about a wedge bolt or a sleeve bolt? If wedge, its the hanger that is spinning, correct? Not the bolt? Seems to me loctite is a good potential bandaid for this bolt. More intrusive methods like recessing the bolt-hanger contact surface with a chisel, etc? A. glue in is probably a better solution than all that.

If its a sleeve bolt that is loosening, replace the bolt with a glue-in, full stop.

Jim Tittwrote:

With wedge bolts if the bolt is a spinner you cannot usually get the clip to engage to re-tighten them. You may succede if you carry enough tools to lever the whole assembly outwards to get initial engagement or not.

As noted above the European codes also prohibit their use as they can no longer be assessed or re-tensioned. Only double-nutting is permitted.

I've experienced this.  If the bolt is spinning, I can sometimes get it to hold still by attaching my weight to the hanger.   

Locktite or nylon nuts would make it harder to get the bolt to hold still so you can loosen or tighten the nut, especially with 3/8 wedge bolts where the threads are more likely to get damaged during installation and be resistant to tightening or loosening

For wedge bolts Loctite has the same problem, if you threadlock the nut and the hanger moves you can't usually break the threadlock bond because with no bolt tension the bolt would rather turn before the threadlock bond breaks. The breakaway torque is roughly half the maximum torque value for the bolt, for example Permabond MM 115 it's 16Nm for an M10 bolt which would be torqued to 30Nm. The only solution with threadlock is to carry a blowtorch.

Jim Tittwrote:

With wedge bolts if the bolt is a spinner you cannot usually get the clip to engage to re-tighten them. You may succede if you carry enough tools to lever the whole assembly outwards to get initial engagement or not.

As noted above the European codes also prohibit their use as they can no longer be assessed or re-tensioned. Only double-nutting is permitted.

Just out of curiosity, is there a thinner nut (like half thickness) available to use as a double nut setup for wedge bolts?

Of course. Home Depot Jam Nuts to start with.

So what brand hanger is on the bolt now and how much stud is proud of the nut?

A properly tightened wedge bolt with an older Petzl or Climb Tech hanger will resist a lot of side force. 

A Fixe  or new Petzl hanger make a nice lever on bolt to loosen it. 

I dont think anyone has mentioned this?

Something else not mentioned, you could put a small amout epoxy between the hanger and the rock. Do it late in the day so it would cure over night. Simpler than couter sinking the hanger. Tighten to full specified torque! If that doesn't work put in a twist rod glue in. 

timothy fisherwrote:

So what brand hanger is on the bolt now and how much stud is proud of the nut?

A properly tightened wedge bolt with an older Petzl or Climb Tech hanger will resist a lot of side force. 

A Fixe  or new Petzl hanger make a nice lever on bolt to loosen it. 

I dont think anyone has mentioned this?

Something else not mentioned, you could put a small amout epoxy between the hanger and the rock. Do it late in the day so it would cure over night. Simpler than couter sinking the hanger. Tighten to full specified torque! If that doesn't work put in a twist rod glue in. 

It's not sideways force, it's torque that is the issue

Read the thread title.

Maybe add another intermediate bolt or move it.  I’d definitely pull the 3/8 and drop in a 1/2”x5 hilti/similar SS and torque it down.   Ultimately it’s time for a glue in.