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looks easy from here
climber
Ben Lomond, CA
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Oct 26, 2015 - 12:00pm PT
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I'm on the outside looking in on this issue, but the problem with dissolving bolts that springs to my mind is that you couldn't "replace as you go". You'd have to climb to bolt 1, come back a week later, replace bolt 1 and climb to bolt 2, come back a week later, etc. And then you'd still have to bail off a single bolt that has been acided (for lack of a better word) every time.
Unless you felt comfortable clipping a whole string of acided bolts, and relying on biners that may have picked up some incidentally...
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Greggonator
Trad climber
Broomfield, CO
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Oct 26, 2015 - 03:54pm PT
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Banquo-
Very cool. I had wondered if that would be possible without power tools. Still sounds tedious. Did you try adding water to the hole while you were turning it? Or perhaps a bit of abrasive solution (dilute carborundum paste)?
Grubs -
You will have to make your own custom coupling nut. You'll need a vise, a 29/64" bit and drill, and a 1/2-20 tap to mate with the SDS drill chuck adapter part. Takes 15 or 20 minutes. Drilling a 1/4" transverse hole works a little better than a jam nut.
Another cheaper way to make a spinner that I might try again is to take a dead SDS drill bit and lop off the end about 3/4" from the drill, anneal it with MAPP gas and tap it at 3/8-16. I tried this and heated it up to cherry red and cooled it as slowly as possible. I think it cooled a little too quickly because the threads sheared off while I was cutting them. If this were successful you could use a standard unmodified 3/8 coupling nut.
-gg
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Studly
Trad climber
WA
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Oct 26, 2015 - 07:07pm PT
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Have you ever tried Remgrit hole saws?
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AE
climber
Boulder, CO
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Oct 27, 2015 - 11:11am PT
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I'm perhaps not being politically correct, by posing these (rhetorical) questions, but:
If any method results in a damaged/enlarged/altered hole that is unsafe for re-bolting anyway, why isn't just chopping/patching preferable?
Also, aside from small diameter limiting strength, if the bolts are that hard to remove, might that not suggest they are actually still relatively solid and so don't need replacing?
Thinking analogous to carabiner load testing below failure, it might sometimes be useful to design a below-failure threshold test for in situ bolts. An outward levering drop/impact test minimum for protection bolts, and higher one for anchors, might be more appropriate especially as hundreds of bolts might be fine, while good-looking ones are actually crap.
Diameter and hangar vintage aside, every unfamiliar bolt is still an unknown with no assurance that it was placed by skilled hands or that it will perform as advertised, or that its uncertain expiration date has been reached.
So, admit it, we've all clipped in, given it the old "yank test", then surrendered our safety to it. Faith over science - not much really changed.
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Greggonator
Trad climber
Broomfield, CO
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Oct 27, 2015 - 11:37am PT
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AE-
Removing a wedge bolt and replacing it with a SS sleeve bolt in the same hole is a worthy goal. Hole count does matter to many climbers and at least a few land managers. Clipping stances are sometimes limited for lead bolts, too.
Boring out the hole for a 1/2" SS 5-piece probably ensures that 50 years from now the bolt could still be removed without violence and that the same hole could be re-used yet again. Asking for wilderness drillers to ream to 1/2" by hand is a tall order, though.
Waiting for it to rust solid probably ensures that it won't be extracted and will end up chopped and patched instead. I'm not too worried about 3/8" wedges shearing off at the hanger, but I've had rusty ones slide out of the hole under shockingly little tension.
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Banquo
climber
Amerricka
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Topic Author's Reply - Oct 27, 2015 - 02:54pm PT
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My problem here has been finding coupling nuts to couple the 3/8" bolts to my drill and to my hydraulic punch driver. Do you have any recommendations or do you tap your own coupling nuts? McMaster-Carr didn't seem to have what I need. I think what you mean is a thread adapter. Very easy to make if you have a lathe which I suppose most people don't have. A local machine shop could make one in a few minutes. You can also weld or silver solder two nuts together. Perhaps something like this could be made to work:
http://www.performanceaudio.com/item/k-m-stands-218-thread-adapter/32278/?gclid=CjwKEAjwwbyxBRCS74T049iEp0wSJACkO5v1JvernhfO3rUbK9TU2Hj7A_485ZvQnXi-9mGtDqRQohoCHg3w_wcB
yankee screwdriver I have a really nice and very big Yankee driver but I don't think it can generate enough torque.
Nitric acid eats metal. Nope, I'm not going there.
Did you try adding water to the hole while you were turning it? No, I did not. I wanted to try doing it dry just to see how it worked. The less stuff the better but it may be worth the trouble. I'll try it.
If any method results in a damaged/enlarged/altered hole that is unsafe for re-bolting anyway, why isn't just chopping/patching preferable? The ideal goal would be to remove the bolt and reuse the hole even if it needs to be enlarged for a larger diameter bolt. The less impact the better. I doubt any of the patching I've seen will last more than a few years.
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Jawon
climber
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Oct 27, 2015 - 04:21pm PT
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Honestly I can't quite make sense of what's going on in those photos with the two wrenches, but it reminded me of a bicycle crank puller. Pertinent part starts at about 2:00...
[Click to View YouTube Video]
Best of luck. Seems like a fun brain puzzle.
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Screwmar
Trad climber
Compton (seriously)
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Oct 28, 2015 - 01:08am PT
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"since i dont feel like spending money to continue, i have stopped working for now"
Quitter.
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Dingus McGee
Social climber
Where Safety trumps Leaving No Trace
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Oct 28, 2015 - 04:15am PT
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Greggonator and AE,
there is a simple test to determine if good bolts are:
Loosen the nut and then re-tighten it to the manufacture's torque. If the bolt can take the torque it can take the shear loading -- rusty or not.
A steel cannot exhibit full tension capacity and have zero shear strength despite they appear orthogonal in a simple analysis such as the Mohr's circle failure theory.
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Greggonator
Trad climber
Broomfield, CO
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Oct 29, 2015 - 04:39am PT
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Dingus -
I agree with you. The problem is one of frequency of inspection and the number of bolt replacement volunteers versus the number of aging bolts. If we abandon the goal of cleanly extracting stud bolts to re-use as many holes as possible then simply proof testing each bolt and leaving it alone is a fine strategy. The problem I see with that is when that bolt only gets a visit from a torque wrench every 15 or 20 years. By the time they are bad they are also tricky to remove and more likely to break off when you try.
The lawyers versus the volunteers can also be an issue. If you replace bolts anonymously/under cover of darkness then nobody can sue you. If you are known to do route maintenance and you leave a rusty bolt in place because you think it's fine and it pulls and hurts somebody...
Yeah, I know: the risks are patently obvious and nobody has ever been successfully sued for something like that. I still prefer to leave behind a 1/2" stainless 5-piece whenever I replace a bolt because I have faith that it simply will_not_fail. The bonus is that I also have faith that it will be relatively easy to remove a generation or two from now.
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Banquo
climber
Amerricka
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Topic Author's Reply - Oct 29, 2015 - 09:48am PT
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Grubs hydraulic punch driver
The Harbor Fright version for $90 might be adequate. Can one use hydraulic advantage in wilderness areas and national parks?
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couchmaster
climber
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Oct 29, 2015 - 09:52am PT
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I've drilled and cut a lot of rock. Can you guys specify what brands, make, model and size drill bit(s) you utilized to do your tests? Additionally, where you purchased them.
Also, generically, as the rock gets harder, you need to slow down the drilling speed. Use of water (or oil in a contained system) is always recommended in stone cutting with diamonds as well. I see the fella who spent $100 on his drill bit successfully got 3 holes was using water. In particular, can you specify what brand, make, model and size drill bit you were using? It might be possible that the diamonds sintered to the inside which caused the steel wedge anchor to be cut can be ground off to make a workable version that goes straight down the wedge anchor using it as a guide?
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Greggonator
Trad climber
Broomfield, CO
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Oct 29, 2015 - 11:22am PT
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Banquo-
We bought the Harbor Freight one before we got a real Greenlee. Although it does work well, it isn't practical because it is freakin' huge and heavy. Very unwieldy when hanging on a rope.
Couchmaster-
We were using these bits:
http://www.ukam.com/webcatalog_drills_ordering.htm
model: 4000102SG
We just used water as our coolant, and we probably didn't use enough. My friend, Matt, just ordered one large enough to fit over a ring bolt with the intention of core-drilling and replacing with a glue-in. He described our failures to the folks at UKAM and they said we overheated the bits. Some of them broke when we were just a few seconds into the cutting, though - those broke from racking them sideways.
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Banquo
climber
Amerricka
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Topic Author's Reply - Oct 29, 2015 - 02:42pm PT
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Couchmaster -
I made the bits in this thread. It's been a few years and I no longer recall what diamond bit I used but it can be seen here:
http://www.supertopo.com/climbing/thread.php?topic_id=1268908&msg=1273879#msg1273879
The diamond bit will happily drill through the steel so to work, it would have to be designed to follow the bolt. In my try with a diamond bit, the bolt was gone and only the wedge and sleeve were left in the hole. The bit would not have been deep enough on the inside to fit over the bolt. The bit needs to be 3" deep on the hollow inside. I'm sure somebody could make one.
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grubs
climber
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The Harbor Fright version for $90 might be adequate.
This is what I have, and as Greggonator said it is heavy and pretty unwieldly, but I believe it will do the job for those of us who don't have access to a Greenlee.
Can one use hydraulic advantage in wilderness areas and national parks?
Well they let you use camming devices. Given that it makes no noise, I think you'd be fine.
You'll need a vise, a 29/64" bit and drill, and a 1/2-20 tap to mate with the SDS drill chuck adapter part
After doing my research I understand this now and almost have everything I need to do this. One question for you machinist pros- If I purchase a 3/8"-16 to 1/2"-13 thread adapter, can I just run my 1/2"-20 tap over the 1/2"-13 threads and be done with it? Note this is just for spinning the bolt with low forces involved.
Drilling a 1/4" transverse hole works a little better than a jam nut
I still don't understand what this means, can you elaborate? I was planning to use a jam nut.
Thanks everyone for the great info.
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grubs
climber
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Thanks greggonator, all clear now. Incidentally, in your video you also answered my question about running the 1/2"-20 tap over the 1/2"-13 threads- "generally not a great idea but works for some situations".
I'll report back in a week or so after I've had time to make the thread adapters and try removing some bolts in my backyard test rock.
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grubs
climber
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Couchmaster,
In regards to the diamond core drill failure, the drill in question was a custom 9.9mm Inside Diameter, 12.0mm Outside Diameter sintered (metal bond) diamond core drill, drill depth 2.75”, special ordered at www.ukam.com. It is highly likely that I overheated the bit by spinning it too fast, too aggressively and without enough fluid (water). The bosch hammer drill with the home-made water cooler would make all of those things very easy to do, especially given that I have zero experience using diamond drills.
Removing the diamonds sintered to the inside of the drill to make it track better down the bolt certainly sounds like a good idea. But I still think in the end this just isn't the most practical or cost effective method, given the success everyone is having with the spin-and-pull method.
If you or anyone else is interested, I'd be happy to ship you the probably useless diamond drill and water cooling adapter to experiment with.
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cragnshag
Social climber
san joser
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timely bump, no?
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Banquo
climber
Amerricka
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Topic Author's Reply - Nov 8, 2015 - 07:13am PT
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Thoughts: Slide hammer attached to the bolt. Would the hard and fast method work over the twist then slow pull?
If by hard and fast method you mean simply pounding the bolt out without the spinning part, I don't think it would work in good granite but might in softer rock. Simply pulling just breaks off the bolt.
I've thought about a slide hammer. I'd call it something like a bolt funker though.
The puller I used in the original post is simply what I had on hand and I think every aspect of it could be improved but my first interest is to see if I can get a groove using human power. First things first. I think the puller that Greggonator is working on is a good solution. I have a small lathe which would simplify much of the fabrication.
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