Working on new method to remove wedge bolts

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Messages 1 - 57 of total 57 in this topic
Banquo

climber
Amerricka
Topic Author's Original Post - Oct 18, 2015 - 04:44pm PT
In the past I have tried pulling on bolts until they break and then fishing out the sleeve and wedge.
http://www.supertopo.com/climbers-forum/1268908/Pulling-a-Wedgie

I have also tried to drill out the bolt with a ˝” diamond hole saw. Note that a standard hole saw might also work but I have never seen a ˝” one.
http://www.supertopo.com/climbing/thread.php?topic_id=1306518&msg=1306518#msg1306518

Neither of those approaches is practical.

The best method I have seen so far is spinning the bolt in the hole until a groove is worn in the wedge. The groove lifts out the sleeve when you pull the bolt. This method requires a power drill so cannot be used in National Parks or Wilderness areas.
http://www.mountainproject.com/v/inexpensive-bolt-extractor/109487927

I decided to see if I could make a ˝” impact core drill that could be used to drill down past the sleeve until the whole assembly can be lifted out. If the drill is the right outside diameter, a ˝” bolt can be placed. According to the ANSI standard B212.15 the outside diameter of the bit should be between 0.520 and 0.530 inches. The inside diameter should just fit over the bolt so that the bolt guides the bit. I decided on a stepped inside diameter with a main portion 0.380” to fit a 3/8” bolt and 0.390” near the tip to be sure and fit over the sleeve. For comparison, the ANSI diameter for 3/8” drills is 0.390 to 0.398 inch. What I ended up with is essentially a ˝” steel hole saw with a very deep socket.

A very hard, tough and wear resistant steel is required since I don’t have the tools or skills required to work with carbide. (Carbide is more correctly referred to as "tungsten carbide" and is more of a composite than an alloy. Carbide tools contain materials other than or in addition to tungsten carbide.) Since carbide is not an option right now, I decided to go with a tool steel. There are hundreds of different steel alloys referred to as tool steels.

High speed steel (HSS) is a class of tool steels that was developed to hold its temper at high temperatures. Since it can get hot without losing hardness, you can cut and drill faster with tools made from it hence the reference to high speed. HSS steel is troublesome to harden and temper. Before hardening by quenching, the various types of HSS usually need to be brought up to temperature in careful steps and then quenched in water, oil or air depending on the type. Tempering generally needs to be done several times. Other types of tool steel are generally simpler to heat treat but it depends on the type.

As a first try I decided to use what I have in the garage. The only piece of tool steel on hand was a length of ˝” diameter drill rod I had bought it to make a reamer to form A-Taper drill holder sockets. It is type O1 (An “oh” not a “zero”) which is an oil quenched steel. O1 steel is easy to machine and heat treat but does not have the best wear resistance. I figured it was good enough for development purposes. I shaped the bit on the lathe and since I couldn’t think of a handier way, I shaped the cutting teeth with a triangular file. I then heated only the cutting end up to cherry red with a torch and quenched it in oil. Just to see if fully hard would work, I didn’t temper it. I set a bolt and started hammering the bit. It lasted a dozen or so blows and the tip shattered. It did seem to have been working though.

The second try I did pretty much the same but tempered the steel down to what I figured would be about R55 (325° C). The drill worked very well until the outer edge of the teeth wore down which left the tip of the drill beveled causing it to jamb tightly in the hole. I did get about ˝” deep without much trouble and it was going very well while it went.

So, I need to find better steel with very good wear resistance or find somebody who can fabricate carbide. Looking through the various types of tool steel, I have found two that appear to have good properties, M4 and A11. A11 is also known as CPM 10V.

M4 is a tool steel and requires careful heat treating as described above. A 5/8” x 36” piece with shipping runs about $300 on Ebay. Choose 5/8” so it can be turned down to 0.530”.

A11 has simpler heat steps but due to problems with decarburization (loss of carbon from the steel), it should be heat treated in a molten salt bath to isolate it from oxygen. Fooling around with molten salt in the garage sounds like something I’d rather not do. A11 is harder to find but costs about the same as M4. www.hudsontoolsteel.com

Since I don’t feel like spending the money to continue, I have stopped work for now.






Mungeclimber

Trad climber
Nothing creative to say
Oct 18, 2015 - 06:43pm PT
if you make the half inch hole, then you have either:

1. Use the hole and back fill with a half inch bolt in the case of replacing.

or

2. Epoxy the hole with camouflage rock dust to fill the hole to prevent it from being reused with a larger bolt in the case of restoration efforts (I.e. fixing retrobolts)


neither is relevant to your problem, just thinking out loud.

Have you talked to John G about this? Or perhaps AROCA? There are ways, without a motoroto.
Juan Maderita

Trad climber
"OBcean" San Diego, CA
Oct 18, 2015 - 06:46pm PT
Very cool Banquo. Always the innovator and willing to put the time into it.
Has anyone ever tried using an "eggbeater" type hand drill with a diamond core drill? Is mechanized, not motorized, acceptable in wilderness? Diamond core drilling would also need a water spray bottle.
http://www.garrettwade.com/beautiful-german-made-hand-drills-gp.html
Clint Cummins

Trad climber
SF Bay area, CA
Oct 18, 2015 - 07:44pm PT
Interesting approach.
The teeth should hold up longer in non-granite rock like at the Pinnacles.
But the rounded edges and binding is familiar from the days of drill bits without tungsten carbide tip inserts.

Munge,
If one is just chopping a 3/8", you can just break the top of the bolt off by torquing very hard on the nut (long handled wrench or breaker bar).
Or you can use washers/spacers and often break it at the wedge down in the hole.
(Not suitable for replacing in the same hole, though, as Banquo has shown it's hard to get the wedge/cone out).
Banquo

climber
Amerricka
Topic Author's Reply - Oct 18, 2015 - 08:31pm PT
There are ways, without a motoroto.

Munge, post some details. I like to learn about things. BTW, if you are ever headed out for moderate climbing, or even a photography trip, let me know. I've lots of free time these days.

Have you looked at carborundum hole saws?

Please, please provide a link to where such things are available. As I said above, I have not been able to locate 1/2" hole saws of any sort but have located 1/2" diamond core drills. I have, as an experiment, tried drilling holes with a common, bi-metal hole saw by pounding on it with a hammer and found that they drill okay -- but, I can't find them in 1/2" and, they are not long enough to drill out a standard bolt. Carborundum is an abrasive and not as good of an abrasive as the diamond that I have already tried - again, please provide some background and I will be happily surprised to find another material to consider. I like input but please do a little background research before you post. If you can come up with something useful, I will reward you with praise and free custom gear.
cragnshag

Social climber
san joser
Oct 18, 2015 - 08:32pm PT
I think you should try the molten salt bath. I heard it's good for the skin. When you are done Gus can use it for a salt lick.
MisterE

Gym climber
Being In Sierra Happy Of Place
Oct 18, 2015 - 08:33pm PT
The links here and the info is so good.

Thanks, all - for your R & D.
Greggonator

Trad climber
Broomfield, CO
Oct 19, 2015 - 05:24am PT
The diamond hole saws are very fragile. We broke several of them during our tests (at ~$60.00 a pop). The cutter head would break off if the bit overheats or if it binds up on the bolt. The size bit we had removed about 0.015" of metal off the threads of the stud.
The short length of all the commercially available ones was also an issue.

The spinning technique has worked very well for me. Really rusty Redhead style wedges can be pulled with the Doodad tool without spinning - The rust disables the collar and it is essentially a nail instead of a mechanical bolt.
With that style of wedge, I think that if you could keep 10 or 20 lbs of outward pressure on the bolt while turning it a few revolutions (even without a power drill) it might damage the wedge enough to pull it out without breaking (when it's already rusty). The collar has a squared off leading edge. KB3's have a tapered leading edge and take a lot of high-speed spinning before they give up the fight.
Banquo

climber
Amerricka
Topic Author's Reply - Oct 19, 2015 - 09:15am PT
I think you should try the molten salt bath.

Sure Bob! Bring the kids over and we'll have fun melting sodium chloride. It melts at 801 °C (1,474 °F). I wonder what happens if you throw water into it.
Mungeclimber

Trad climber
Nothing creative to say
Oct 19, 2015 - 09:27am PT
thx Clint! Admittedly, I have a very small crowbar. I didn't have much luck with a 3/8 split shaft and stopped trying to do wedgies for a long while. In the harder rock, it doesn't beat the heck out of the rock?




huffing salts?

I think that's an explosive idea!!



Dan, you got it. That's all I'm doing right now while the shoulder gets back. Took the shoulder out for a spin and the inflammation is back. But going to Pinns for Kalen's gig and Pinns appreciation days. You going?
Plus I got some weekends in November up on SPH.





Scylax

Trad climber
Idaho
Oct 19, 2015 - 10:48am PT
I confess that I would much rather read a thread about bolt removal instead of bolting(dumbing down) routes!!!

Also, looks like nice work there.
Banquo

climber
Amerricka
Topic Author's Reply - Oct 19, 2015 - 11:15am PT
Scylax -

Don't click on those threads, your brain will rot and you will begin to spout gibberish.



Munge -

1) I have not shown this to John G

2) I don't know what AROCA is.

3) I did not sign up for Pinnacles Appreciation days which I believe is this weekend.

4) I don't know what Kalen's gig is.

5) If you head up to SPH and need somebody to drink your beer, send me an email and I might tag along.
Banquo

climber
Amerricka
Topic Author's Reply - Oct 20, 2015 - 09:56am PT
Since I already had the two bits, I decided to try again. I annealed them, cut off the ends and filed new teeth. The first bit that I tested without tempering had long teeth so I decided to try an non-tempered bit with short teeth and see if it worked better.

First I tried to continue the hole I had started but the walls were slightly tapered from the earlier bits and it simply stuck. So I started a new hole without a bolt and It drilled pretty well for about 3/8" when the teeth started to go. A couple teeth broke off and the inside face of others chipped off. Since the bits are straight sided, binding was an issue.

Second try I cut teeth and then turned down the outside diameter above the teeth in hopes of reducing binding. This left a small edge which probably caused stress concentration. I placed a new bolt and tried to drill around it but the teeth broke off pretty fast.

So far I think to work a bit needs to have teeth with some outward set to reduce binding. A better material than O-1 tools steel is required.

A real problem is that as you drill down along a bolt you are chipping off the edge of the hole, the edge chips off inward causing a taper to the hole which binds the bit and breaks the teeth off inward.

Banquo

climber
Amerricka
Topic Author's Reply - Oct 23, 2015 - 01:50pm PT
So I have decided the hollow drill approach isn't practical with the materials that I work with. I also think the bits wouldn't last even with the best of steels.

Back the the spinner method. I made a hand crank bolt spinner. It isn't a practical version but I simply used what i had in the garage. The spinner crank is simply a box end wrench with a kludged handle. The connector to the anchor bolt is a 3/8" coupler nut, bolt and jamb nut. A piece of flat plate was used to apply tension to the bolt while turning. The puller is the one I used in the earlier thread (linked at the top of this thread). All the equipment can be improved for weight and portability but this was just a feasibility check. Lots of ways to improve this rig.

1) Remove hanger.

2) gently knock in bolt until just loose.

3)Place pry plate over bolt.

4) Screw on coupler nut until it almost draws tight.

5) Screw bolt into coupler until it locks against anchor bolt.

6) Tighten jamb nut.

7) Crank while keeping tension on the bolt. It is not possible in this lifetime to crank for too long.

8) Remove crank, coupler, bolt and nut.

9) Attach puller and apply as much tension as you can without breaking the bolt.

10) Loosen puller, knock the bolt back in and pull again.

11) Repeat 10 as desired.

12) repeat 1 through 11 as required.

13 Have lunch

14) repeat 1 through 12.

Actually, this took less than an hour but it seemed longer. I didn't really make a groove in the wedge that would lift out the sleeve but I did gouge up the surface which I think helped. The bolt would probably, eventually come out if you just kept pulling on it and knocking it back in.

the main things that might go wrong are breaking the bolt, bending the bolt or buggering up the threads.

I don't know how this will work with rusty bolts. The redhead bolts I used have a stainless sleeve and a carbon steel wedge. The stainless is probably softer than the carbon so the creation of a groove might never happen. There are so many types of wedge bolts, in varying condition, success will probably be highly variable. You can always try and if it doesn't work, chop and patch.






bhilden

Trad climber
Mountain View, CA/Boulder, CO
Oct 23, 2015 - 07:59pm PT
Dan,

so step #7 in your method is similar to Greg German's (Gregger Man) spinning the bolt with a power drill in an attempt to score the cone shaft so the cone will not ride down the bolt when tightened. Next, try to pull the bolt out and hope the cone won't move and expand.

Cool! There may be a project at the Pinnacles with your name on it!
Chris McNamara

SuperTopo staff member
Oct 26, 2015 - 10:28am PT
This thread was included in SuperTopo Climbing News - http://goo.gl/Fhw0av
looks easy from here

climber
Ben Lomond, CA
Oct 26, 2015 - 10:55am PT
Sure Bob! Bring the kids over and we'll have fun melting sodium chloride. It melts at 801 °C (1,474 °F). I wonder what happens if you throw water into it.

What? You're scared of making a little literal lava in your garage? What could go wrong?

[Click to View YouTube Video]
grubs

climber
Oct 26, 2015 - 11:37am PT
Banquo thanks for the continued efforts and good info.

I have also played with the diamond core drill method, and even ordered a custom bit of exactly the right dimensions to fit around a 3/8" wedge bolt. I used a 1-gallon garden sprayer adapted to the core drill for cooling. The first bolt I tried came out like a charm, and I drilled the remaining hole to 1/2" and put a new bolt in. However, things went downhill from there and I eventually abandoned the method for these reasons:

1. The diamond bit did not track down the shaft of the bolt like I expected, instead it was very happy to cut right through the steel bolt. If my entry angle was off even by a tiny bit, I would be cuttin way into the bolt by the time I got to the end of it, leaving an unusable oddly shaped hole.

2. After about 3 holes, the diamond bit was very worn and could no longer efficiently drill holes, possibly because two of those holes involved drilling through the steel bolts due to a poor entry angle as mentioned above.

3. The custom diamond core drill cost me about $100. This might be acceptable if it removed 100 bolts before wearing out, but that didn't happen for me.

4. It was very awkward with the water cooling rig, and a gallon of water runs out quick.

I know some have found success with this method, but after giving it my best shot I agree with your conclusion that for most of us the diamond core drill method simply isn't practical.

I've moved on to the spinning and pulling method that has seen so much success lately (that is, where power drills are allowed). 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.

Anyways, thanks again for the continued R&D and for sharing your experiences.
Brian in SLC

Social climber
Salt Lake City, UT
Oct 26, 2015 - 11:49am PT
I've always wondered, in areas where you couldn't use a power drill, if you could use something along the lines of a yankee screwdriver to spin a bolt...?

Interesting methods!
Rosamond

Trad climber
Truckee, CA
Oct 26, 2015 - 11:55am PT
Nitric acid eats metal. Instead of going through all this mechanical rigamarole, has anyone tried simply dripping a couple milliliters of nitric acid into the system, coming back a week later, and removing the now heavily corroded bolt? Of course, Nitric acid also eats things like climbing gear, so you'd have to be careful.
looks easy from here

climber
Ben Lomond, CA
Oct 26, 2015 - 12:00pm PT
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...
Greggonator

Trad climber
Broomfield, CO
Oct 26, 2015 - 03:54pm PT
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
Studly

Trad climber
WA
Oct 26, 2015 - 07:07pm PT
Have you ever tried Remgrit hole saws?
AE

climber
Boulder, CO
Oct 27, 2015 - 11:11am PT
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.
Greggonator

Trad climber
Broomfield, CO
Oct 27, 2015 - 11:37am PT
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.
Banquo

climber
Amerricka
Topic Author's Reply - Oct 27, 2015 - 02:54pm PT
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.
Jawon

climber
Oct 27, 2015 - 04:21pm PT
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.
Screwmar

Trad climber
Compton (seriously)
Oct 28, 2015 - 01:08am PT
"since i dont feel like spending money to continue, i have stopped working for now"

Quitter.
Dingus McGee

Social climber
Where Safety trumps Leaving No Trace
Oct 28, 2015 - 04:15am PT
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.
Greggonator

Trad climber
Broomfield, CO
Oct 29, 2015 - 04:39am PT
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.
Banquo

climber
Amerricka
Topic Author's Reply - Oct 29, 2015 - 09:48am PT
Grubs
hydraulic punch driver

The Harbor Fright version for $90 might be adequate. Can one use hydraulic advantage in wilderness areas and national parks?
couchmaster

climber
Oct 29, 2015 - 09:52am PT


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?
Greggonator

Trad climber
Broomfield, CO
Oct 29, 2015 - 11:22am PT
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.
Banquo

climber
Amerricka
Topic Author's Reply - Oct 29, 2015 - 02:42pm PT
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.
grubs

climber
Nov 1, 2015 - 03:30pm PT
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.
Greggonator

Trad climber
Broomfield, CO
Nov 1, 2015 - 04:45pm PT
Regarding the 1/4" transverse hole - sorry, didn't finish my thought when I wrote that up. This should clear it up:

http://mountainproject.com/v/111245965

This will show you all the steps in making the puller tool, too:
[Click to View YouTube Video]
grubs

climber
Nov 1, 2015 - 05:05pm PT
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.
grubs

climber
Nov 2, 2015 - 09:19pm PT
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.
cragnshag

Social climber
san joser
Nov 6, 2015 - 01:24pm PT
timely bump, no?
Banquo

climber
Amerricka
Topic Author's Reply - Nov 8, 2015 - 07:13am PT
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.
WBraun

climber
Nov 8, 2015 - 08:20am PT
Let me know if field testing is needed.


Hee hee hee .....
Banquo

climber
Amerricka
Topic Author's Reply - Nov 8, 2015 - 09:10am PT
Come on Werner,

get a groove using human power
WBraun

climber
Nov 8, 2015 - 10:01am PT
Banquo

Your ideas are always great here.

My post was in response to Mike. as he's probably thinking along with me in reference to Erik S wedge bolts recently added on BOR to be removed.

Keep up the good work .....
Banquo

climber
Amerricka
Topic Author's Reply - Nov 8, 2015 - 11:07am PT
I thought "get a groove using human power" was pretty funny. My wife has tried to explain humor to me. She says humor doesn't work on the internet.
Greggonator

Trad climber
Broomfield, CO
Nov 8, 2015 - 11:53am PT
Warbler -
If I understand you correctly you would be putting a lot of pulling force on the bolt while turning it. That sort of torsion breaks the bolt every time for me. That's why I went to a square spacer for the Doodad tool with a square nut on the Acme threaded rod that keeps the whole mess from rotating when you tighten the big nut.
Geir Hundal's Hurley bolt puller can work, too. I don't like the three-point base because it doesn't support the rock in the cone of stress created by the wedge and you could get a dinner plate rock failure. It's also more expensive/difficult to manufacture. (http://www.supertopo.com/photos/28/54/406949_27758_L.jpg);
Banquo

climber
Amerricka
Topic Author's Reply - Nov 8, 2015 - 01:47pm PT
Since we are talking about this, I decided to go out to the garage and triy again. This time I used some rock dust and water to help with grinding an edge on the wedge. I think it worked better and I only spent about half as much time spinning at I did last time.

After spinning, I pulled on the bolt until it got tight. It came up maybe 3/8". I knocked it back down and pulled it a couple more times until the sleeve wore out enough so it came out. I did spall some surface off the rock so I probably pulled too hard near the surface. I should have spun longer. I think I should have pulled more gently knocking it in and pulling the sleeve up more times.

Whole thing, including making some rock dust, took about an hour.



Banquo

climber
Amerricka
Topic Author's Reply - Nov 8, 2015 - 02:57pm PT
The slurry I mentioned was rock dust and water intended to grind a groove in the wedge.
bhilden

Trad climber
Mountain View, CA/Boulder, CO
Nov 8, 2015 - 08:05pm PT
One of the reasons you don't want to be twisting a wedge bolt while you are trying to pull it out is that wedge bolts have a design issue which creates a point of weakness. To allow the cone to be placed on the bolt shaft a portion of the shaft has to be less than the overall diameter of the bolt. This narrower section of the bolt is the point of weakness.

If you just want to break off a wedge bolt and patch the hole it is pretty easy, in hard rock!, to just put a breaker bar on the nut and overtighten the bolt until it snaps.
donald perry

Trad climber
kearny, NJ
Apr 4, 2018 - 08:15pm PT
Sorry if someone posted this already

https://www.youtube.com/watch?v=FjNM8FhiYf4
grover

climber
Castlegar BC
Apr 5, 2018 - 12:22am PT
I'd say that's one successful and speedy first attempt.

Nice work Banquo.
DanMerrick

Social climber
Mo' Hill, CA
Apr 5, 2018 - 08:08am PT
My latest version of Greg's doodad. The all-thread and hydraulic pullers aren't practical.

Ball screw and nut ~$25 on Ebay

Thrust bearing ~$12




BruceHildenbrand

Social climber
Mountain View/Boulder
Apr 5, 2018 - 08:51am PT
Bolt studs don't stand a chance against that device!
Steve Grossman

Trad climber
Seattle, WA
Apr 5, 2018 - 06:54pm PT
Geir Hundal in Tucson has developed several really good bolt pullers. Here are a few videos of them.
[Click to View YouTube Video]
[Click to View YouTube Video]
[Click to View YouTube Video]
I believe that you can get these through the Access Fund if you have some anchor work to get done.
thebravecowboy

climber
The Good Places
Apr 5, 2018 - 09:12pm PT
really wish I had already built the puller. need one now, won't be back anytime soon to this one-bolt station, and I ducking hate crap wedge bolts in Ss!

it would have to be a one-for-one replacement per the Rules
BruceHildenbrand

Social climber
Mountain View/Boulder
Apr 5, 2018 - 11:07pm PT
The ASCA received all of John Bachar's bolting gear. The tool he developed in the 1980's to remove bolts is eerily similar to the Hurley, Sr. which was developed a generation later. I guess great minds think alike.

BTW, I was part of the demonstration videos that Steve Grossman posted. What was interesting about the Hurley SR is that Jason Haas, who is using it to remove a Rawl/Powers 5-piece bolt, pulled the bolt and cone right past the sleeve(which stayed in the hole). Now that's a lot of force.
DanMerrick

Social climber
Mo' Hill, CA
Apr 14, 2018 - 06:01pm PT
Ballscrews are really efficient at converting torque to tension force.




[Click to View YouTube Video]
'Pass the Pitons' Pete

Big Wall climber
like Ontario, Canada, eh?
Apr 14, 2018 - 06:03pm PT
Hey, check your email, eh?
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