Removing a 5-piece

A bolt I placed a couple years ago has come loose, likely due to friable rock a the back of the placement.  I'd like to remove it, and wanted some advice before I just chop and cover up the hole.

The Bolt is a 3/8 x 3 1/2 inch stainless fixe 5 piece placed in limestone.  When placed, I drilled, cleaned the hole, etc, and torqued it with a torque wrench to specs.  I climbed the route a couple of times that summer, and retorqued the bolts just to be sure.  After about a year, I climbed the route and the first bolt had about 1/4 inch of play - it could pull directly out.  When pushed all the way in, it spins, so it can't just be tightened. I came back with a funkness and tried to reset the cone in the threads, but couldn't get it to set. Similarly, hammering the head of the bolt further in didn't help (as some videos suggested)

My guess is that the back of the rock is in a friable pocket of stone - the limestone at the crag is generally good, but pockets of bad rock exist.  The bolt protects a small roof and a pretty tricky move, so I'm guessing it's seen a fair amount of whips, and the pressure of the cone in the back was enough to break apart some rock.  While drilling, I definitely did not notice any difference in the rock - no pockets or softer spots - but that's the best I can think of.  I marked the route with chalk (this was the end of the season), but I'd like to get back to it as soon as the snow clears (so, you know, June).

 At this point, I could get a pretty clean cut with a bolt cutter, push the sleeve back a little, and just camouflage the hole.  Is there a better way, though, to extract the bolt?

Assuming you’re wanting to remove it and replace with a glue in (which would be ideal for stone with a pocket near the cone), this is what i would try. Before chopping it, I’d either clip into the hanger and lean out (or push off the wall) while attempting to loosen the bolt or put a pry bar behind the hanger while loosening the bolt

Drew,

I'd be interested in replacing with a glue in, for sure.  I think the hole, if drilled deeper and wider, could be fine based on the quality of the rock on the rest of the route.  I'm sure I could also probe with a wire once the old bolt is out to see how extensive that weakness is.

Would the thought, with the glue in, be to fill the cavity with epoxy while placing it?

Although it is not clear from your narrative, I gather that the cone is now fixed to the end of the bolt and you cannot unscrew it. If you were to chop the bolt head off, I'm not sure you could core drill around it to a depth of 3.5" with any of the bits I have seen, but it might make it. I recently got some diamond core bits direct from China for ~$10/$15 each (two different types). They work very well in sandstone and I imagine they would cut even quicker in limestone. Drilling upwards into a roof means you would have to alternate drilling/stopping/squirting water to clean out the dust/drilling again. Total pain, but it's the only shot at reusing the hole, I think.
A second option would be to try the Hurley, Sr. tool that pulls directly on the hanger. I'm not sure I would do that in limestone, tho. Might rip out a crater from that depth.
Looks like core drill or patch.

All above is sound advise.  Also, first try backing off the bolt head enough to slip in a few gaped washers, then re-tightening.  Sometimes this works, IF you think the bolt is still sound.

Gregger,

I'm guessing the cone is fixed, though it might not be. So far, I've tried tapping the head of the bolt with a hammer to reset it to no effect.  I tried hammering outwards using a funkness - the bolt comes out about 1/4 inch and then lodges in the hole.  I'm guessing this is where the cone is coming out of the pocket and making contact with the part of the hole that is drilled to the correct diameter.  This obviously didn't fix the problem - the bolt couldn't be tightened, and it still wasn't at depth.  Finally, I tried to pull out by connecting a draw to my harness and to the bolt, and unscrew the bolt under tension.  Pretty awkward and ineffective given the position of the bolt, but it might be worth bringing a catspaw/crowbar to get better tension.  I might be able to unscrew there.

If I'm not able to get it to unscrew, the plan was to chop it, push it back in, and patch it.  I drilled the hole an inch or two deeper than the bolt, so I should have the play to push it in and patch.

For what it's worth, the bolt is placed about 2 feet above the roof, so it's placed regularly - not upwards into the roof. 

Roy - the gapped washers is a good idea. I do think the bolt is sound, and simply getting the cone to back out might mean I can fully tighten. It'd also be obvious if that didn't work, so that's good too. 

If you do manage to unscrew it, a 1/2" bit can usually demolish the 3/8 sleeve and cone. Since it is stainless, a magnet won't help you remove the debris as you go, so it will bind up the bit more and create a less ideal hole. That wouldn't matter to a glue-in, tho.

If you can unscrew it, you can borrow my tap, extractor, draw stud, etc to try to pull the sleeve and cone out.

casey

Casey,

Thanks!  I'll see what happens when I get out there in early spring.  It's the first bolt on Rancho Pequeno at Allenspur.  

Also - sounds like you talked to Graham Charles about potentially organizing some bolt fixing/replacement.  He and I (mostly he) did a bunch of the bolts at Bear Canyon, and many of the newer retaining walls/steps at Allenspur.  Now that I have a little more time and the kid is out of infancy, I definitely want to continue this in spring.  Let me know if you need any help with ongoing projects. 

I had what might be a similar problem replacing a 3/8" 5 piece in that when I tried to unscrew the shaft, the entire bolt would turn (although with a lot of resistance) but wouldn't come out at all because the cone rust-fused to the shaft. Even with bodyweight pulling outwards on the bolt, I wasn't able to unscrew it.

I ended up rigging a 3:1 hauling system to tension the hanger and after tightening the bolt about a quarter turn, I was able to unscrew the shaft. This was an anchor bolt on the top of the cliff where it was pretty flat so it was easy to set up, but may be a little bit trickier on the side of the cliff.