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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Original Post - May 7, 2007 - 04:13pm PT
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I just ordered a box of 50 MKT Taper Bolts (3/8" x 2 5/8") as I wanted to maybe put up some face routes soon. That afternoon I was at the bookstore and saw Long's new 'Anchors' book. I read through the section on bolts and saw something about how Taper Bolts were dangerous and only held 3,000 lbs. maximum on a pullout test ( and 700 lbs. if poorly placed). I was kind of bummed out to say the least.
I know I've read other articles in the climbing mags about how Taper Bolts were hard to place, but I still can't understand why. I've placed well over 150 Taper Bolts and have never had a single problem. By the way, in granite they hold over 5,000 lbs. in a pullout test (not 3,000). Per hole diameter, they are the strongest bolt on the market (correct me if I'm wrong please).
Here's a link to the strength test chart at MKT Fastening:
http://www.mktfastening.com/Products/Mechanical/Taperbolt/taper.htm
These bolts are routinely used by construction workers all over the world with incredibly safe results. Has anybody had any bad experiences with these things? Any failures? Difficulty placing them? Why the bad rap?
Just curious, JB
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mojede
Trad climber
Butte, America
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JB, I've never placed a taper bolt (tons of rawls and hiltis) and was curious as to how your first through tenth experience went with placing them. Maybe they are easier to place once the "learning curve" has been summounted. I trust YOUR placements, but wonder/ worry about those rookies that plunk down the cash for a bolt gun, then head out to the rock to "practice".
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Russ Walling
Social climber
Out on the sand.... man.....
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Duane Raleigh sez here: http://safeclimbing.org/education/dangerbolts.htm
Torque bolts
We didn't find any dependable torque bolts, although some climbers use and swear by the USE Diamond Taper Bolt, which can be strong but usually isn't. To place a torque bolt you tap the bolt into the hole and then torque it down, spreading an expansion cap at the back of the hole to create a friction hold. Sounds good enough, and USE Diamond touts this anchor as the strongest expansion bolt made, but the problem is these bolts don't have any leeway for user error. Torque the bolt too tight and you strip the expansion cap, ruining the placement. Get the bolt too loose and the cap will hold a pullout load about as well as bubble gum on the end of a nail.
We really gave Taper Bolts a chance, setting dozens of them in their optimum substrate, hard rock. We tried to set the bolts by "feel," just as you would when climbing. Half the time we got it right and the 3/8inch Taper Bolts held up to 3000 pounds in a straight pull out. But we blew it with the other half and the bolts slid out of the hole at only 700 pounds. Worse yet, we couldn't tell the good placements from the bad until we ripped them all out.
Russ sez: Seen good ones and seen bad ones. Operator error in all case I've seen. Stripped sleeve being the most common. Long term? Who knows...... Maybe Greg Barnes has some chopper insight to drop in here.
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 7, 2007 - 06:48pm PT
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mojede - We first started using 1/4" taper bolts in Tuolumne when we realized there's got to be something better than Rawl split shaft 1/4" bolts. The 1/4" Tapers were easy to over tighten. I quickly switched to 3/8" Taper bolts about the same time people switched to 3/8" Rawl 5-piece bolts. The 3/8" version is difficult to over tighten.
It is pretty hard to strip a 3/8" Taper bolt. When you look at how the bolt works, it's obvious that you need to place the bolt in its hole and leave the same amount of gap on the outside as there are exposed threads at the tip (a hair less than 1/4"). The bolt should be extremely tight after five full turns (you can actually turn it six times without stripping it). When I first started placing the 3/8" Tapers, I would put a little 1/4" ring of masking tape below the head so I knew exactly how far to push the bolt in before tightening it. After a while, I could tell how much gap was right and I didn't need the tape.
If placed properly, the Taper Bolt is indeed the strongest bolt on the market right now. Mark Blanchard, Bill Russell and I tested one in a granite river rock one day at his facility. It was only tightened three turns (less than the optimal five) and we broke the hanger at 5,300 lbs. in a straight pull out - the bolt was unfazed! We also tested a Rawl 5-piece - it failed at 2,200lbs.
Needless to say the shear strength of the Taper Bolt is also far greater than a 3/8" Rawl 5-piece - over 8,000 lbs. shear.
I guess I can see where some people might leave too much of a gap (more than 1/4") before tightening the 3/8" Taper Bolt and end up with a spinning hanger and I also suppose you could strip the sleeve if you really torqued on the wrench - the bolt gets really hard to turn after five turns however (hard to imagine someone wouldn't realize they are over-torquing the bolt at this point).
I've never encountered a poorly place Taper Bolt (3/8") so I can't say how bad they are. I have encountered poorly placed Rawl 3/8" bolts and pulled them out with my hands (with sling and biner). The point being, you can botch either type of bolt if you don't know what you're doing and once the bolt is in it's impossible to tell if it was placed correctly apart from jerking on it in a straight out manner to see if it flies out!
Bottom line - a correctly placed 3/8" Taper Bolt is stronger than a correctly placed 3/8" Rawl (or any other bolt that I know of). The huge bummer of this whole thing is that once any bolt is placed, the climber will never be able to tell if it's been done properly!
peace, jb
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Dragon with Matches
climber
Bamboo Grove
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Karma dictates the integrity of the bolts is dependent on whether the installer approached from below or above.
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WBraun
climber
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They may or may not be any good depending on the guy who places them.
All I know is if John places the bolt I'm not going to worry about it because John knows how to place bolts properly.
I have seen ......
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G_Gnome
Trad climber
Knob Central
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All I know is if John places the bolt I'm not going to worry about it because John knows how to place bolts properly.
I have fallen on them ......
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KP Ariza
climber
SCC
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John places solid anchors, that we've established (not that he needs em'). I agree w/ Werner that a good anchor has as much to do with the person placing it as it does with the actual hardware itself. For overhanging face routes titanium eye bolts set with Hilti's industrial epoxy can be bomb proof. They are relatively easy to place (though a bit messy)and, as stated above, are regularly tested and utilized in the construction industry. Many routes along the Bay Area coastline are equipped w/ these anchors and after over a decade of use, in the harshest salt water exposd environment, they show zero signs of deterioration.
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BadInfluence
Mountain climber
Dak side
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JB i thought you chopped bolts
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Steve Grossman
Trad climber
Seattle, WA
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Hey John,
Take those Taperbolts back to the store if you can. The main problem with their design is that all of the straight out holding power comes from the soft metal split end piece and the tapered threads. The design can't withstand any movement in the hole or repeated long axis loading without weakening. If you place these things on overhanging routes, they are doomed to fail eventually. Let me know off thread the kinds of routes that you are setting up and I may be able to hand you a much better bolting system to check out. I've been prototyping several combinations. I have been using stainless Powers (Rawl)1/2" 5 piece bolts but they have become far too expensive once my stash runs out.
Contact me JB.
PS EVERYBODY STOP WASTING TIME AND EFFORT PLACING MILD STEEL BOLTS! Stainless Steel is the only responsible option if you want to do lasting, quality bolt work. Cheapness is no real excuse here, think about it.
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 8, 2007 - 11:32am PT
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Badinfluence - rumors, ha! No, seriously, I stopped chopping a long time ago. Anyway, you can unscrew bolts nowadays - no need to chop anymore (if you're into that sort of thing).
Steve, I really can't see how these Taper bolts can move at all once they're tightened - maybe in some softer rock??? They are stainless steel by the way. All the engineering reports give them extremely high marks and they are used in 5,000 psi concrete for some very serious construction situations where failure is not an option. I like them cuz I can place them one handed on the lead with no hammer (just a drill and a wrench).
I'm always on the look out for something better however and I totally agree with you that we should try and place the best quality bolts possible.
Thanx, JB
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WBraun
climber
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Place Bachar approved taper bolt into rock.
Next, long slack piece of static rope clipped to bolt and other end to car bumper.
Now gas it outa there.
If bumper rips off car, bolt is strong .....
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dryfly
Trad climber
utah
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If bolt not strong..Climber driving car eat bolt/hanger to back of head through window...If climber survive, climber is stronger than bolt.
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DrCrankenstein
Social climber
too many places, actually
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Enough with all this nonsense...
JB, I'll clip a bolt you placed anytime! When do we get to hear about the new area???? I'm intrigued!!! We talkin' like Dexter Canyon style? Cause yer box o'fifty will go far like that.
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KP Ariza
climber
SCC
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Glue in's or stainless wedge anchors-
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Howie
Trad climber
Calgary, Alberta
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All this talk of weak bolts makes me shiver. Never placed one in my life but do use them.
Sounds like we are heading to small metal plates on each bolt detailing date, time and person placing them!
Seriously how do we really know the interity of any bolt?
Nothing like a whacking big piece of aluminium jammed in crack for me. I know, not always possible.
Howie.
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Pistol Pete
Trad climber
Pasadena, CA
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Why don't you just use a torque wrench and tighten to the right specs. Worked for me with FIXE wedge bolts. (Had to e-mail Spain to get the right specs)
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Howie
Trad climber
Calgary, Alberta
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Hmmm power drills, torque wrenches, what next - pull test equipment?
Surely bolts should be placed with some degree on confidence without resorting to a torque wrench. I realise a wrench is neeed to tighten them in the first place.
Howie
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Brutus of Wyde
climber
Old Climbers' Home, Oakland CA
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Zeemac rivets. And don't fall.
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Steve Grossman
Trad climber
Seattle, WA
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Hey JB- Didn't mean to be too hard on your hardware! If the taperbolts that you have are stainless steel and of recent manufacture then that would cover most of my concerns based on the design 20+ years ago. One handed installation is a big plus but I've gotten used to the side hammer jab to set the Powers variety. The big advantage of the Taperbolt design is full bolt diameter to match hole size. The Powers design loses hole diameter to the outer shield. As long as you torque to specification you should remain golden.
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 8, 2007 - 10:08pm PT
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Darryl Cramer - yeah, those Hilti bolts look interesting. I went to the website but couldn't find any specs on strength. What kind of specs does the 3/8" x 3" bolt have? (pullout and shear). Have you ever placed any 3/8" ones?
Steve - Thanx for the slack. I still have concerns about ANY bolt so I do like to hear what others think - especially if they can find a fatal flaw in the system. When I first saw the Taper bolt I also couldn't believe it would be any good. After testing them I'd say they are pretty bomber however and they've withstood the test of time (20 years time anyway).
Steve - On another note - how is it drilling a 1/2" inch hole as opposed to a 3/8" hole? On the lead???
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Clint Cummins
Trad climber
SF Bay area, CA
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Darryl,
Amazing numbers for tensile on those coil taperbolts. I keep thinking it is only the thread depth that is holding, but really it is several threads holding in parallel. Of course in shear they can't be beaten. Too bad they do not seem to be available in stainless.
For good granite new routes I have been using 3/8" x 2.25" Stainless Steel wedge bolts, mainly because they are SS and cheap (under $1 each). They could be placed with one hand, but a hammer is needed. The "thread depth" relative to the coil taper bolt looks nicer, although the surface area of that one right is not too large. In shear they are a little weaker, since the hanger is on the threads. The nut can loosen as well. And they cannot be easily removed.
For softer rock, I use the Powers 5-piece. The sheath and threaded cone give superior surface area contact. ASCA uses these in SS for replacement. SS is about 5x more expensive, unfortunately. They also generally take 2 hands and a hammer to place.
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 9, 2007 - 10:17am PT
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Darryl - Yes those specs do look good - stronger than the Taper Bolt. It's hard to believe Hilti doesn't have a stainless version - they usually have some of the best stuff out there quality wise.
Edit: Any links for the Powers 5-piece?
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Steve Grossman
Trad climber
Seattle, WA
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JB- I am assuming that you are hand drilling these holes. If so, expect to take about half again as long. My personal record for drilling 3/8" holes on tough stances is about six or seven. Sounds like the smaller hole size would make for a less hellish outing for you. Most of my drilling these days is maintenance related rather than new projects but I generally hand drill all of the 1/2" hole that I fill. It helps to have been swinging a hammer for thirty years!
Clint- My big concern with the Thunderstud type, collar and cone end bolt design is the amount of fatigue left behind by the threading during manufacture. Whenever a solid rod is threaded, considerable cross shearing due to applied torque is present. The area at greatest risk is the threading termination point which is usually exactly where the force is applied under load during normal installation. You have a 3/8" solid bolt but the design is such that it is effectively reduced to 1/4" and you are loading the most tortured area of the metal. Couple that with being forced to trust your whole show to the dainty little dimpled lock collar and I won't use them. Upping the size to 1/2" gives you more beef and much less chance of material failure due to stress flaws. I also have a problem in principle with a bolt design the tightens in the same directional mode as it would fail. Cheapness is the only plus here IMO.
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Howie
Trad climber
Calgary, Alberta
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Steve, what type of threading are you refering to with regards to cross shearing?
Howie.
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Steve Grossman
Trad climber
Seattle, WA
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I am referring to twist shearing due to the torque introduced during the threading process. Small diameter lag bolts suffer from the same sort of weakness and will often shear off right at the thread termination. I don't rely on lags in my contracting work either.
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the kid
Trad climber
fayetteville, wv
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bachar, different bolts work best in different types of rock, so there is no end all perfect bolt for each route.
I agree with grossman, stainless is the only way to go for long term anchors! sorry to say in my dirt bag days of rifle and potrero i could only afford non stainless...
i have always liked the 5 piece rawls but here at the new the rock is too hard to place these. they screw up a ton when you pound them in before tighting...
so we use standard screw top type stainless rawls..
now for slab, vert to mildly overhanging hard rock like granite and new river sand stone- the petzl long life is the bes there is- stainless, easy to place as it is pound in the pin bolt...
but when it gets steep these are not the best option...
i think those tapers were better than 1/4 rawls back in the day, but now there are better options for the power drill...
ks
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slobmonster
Trad climber
berkeley, ca
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I don't think I'm personally familiar with the Taper Bolts; the only thing I've seen that look familiar are those f-ed up Petzl "self-drive" jobbies that were popular in some areas.
One simple question: are they (at all) removeable? Though it's tricky, one can yank a Rawl/Powers 6-piece, enabling replacement using the same hole...
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 9, 2007 - 02:45pm PT
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slobmonster - yes they are removable too.
Kurt - the 3/8" is insanely better than 1/4" we used to place. Check out the link at the start of the thread for specs.
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Off White
climber
Tenino, WA
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Kurt - The New, while hard, is a sandstone, right? I've had problems with the Powers 5 piece bolts in the softer sandstone on my home crag, but the issue seems to be the little plastic cap on the cone coming off and the gritty sandstone debris clogging the threads - the bolt just keeps spinning rather than tightening up.
If that's the problem you're experiencing, the fix Steve turned me on to may work for you as well: before pounding in the bolt, pull the cap and fill the cone with a spitwad. Not that stuffing a small wad of toilet paper into a possibly dry mouth is any fun, but I haven't had any problems since I took up the practice.
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slobmonster
Trad climber
berkeley, ca
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Re: Rawl/Powers 6-piece bolts:
I make a habit of progressively hand-tightening the hanger as I tap in the bolt. This can help keep the cone from spinning off.
If you do end up with a spinner, clip a draw to the hanger, and pull straight out as you attempt to tighten it. This can sometimes allow you to re-acquire the cone.
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Clint Cummins
Trad climber
SF Bay area, CA
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Steve,
Yes, the cheaper wedge type bolts (cone and ring) are weakened by the standard method of cutting the threads. Tom Addison has explained this to me as well. He recommended for this type of bolt to use one where the threads are milled instead of being cut (such as the Petzls). Still I think the strength numbers are much better than 1/4". And I agree, their main reason for use is cheap SS. My excuse at present is that I use them on obscure new routes. I wouldn't use them for rebolting. I also agree that the "dimply ring" on the wedge bolts is not good for soft rock - too little surface area. It should be fine on good (hard) granite, though.
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Mark Hanna
climber
Seattle, WA
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Hi All-
I am Darryl Cramers friend who uses the Hilti HCA Coil anchors. I have been using them in compact granite since about 2001, and in industrial settings (temporary worker fall protection anchorage)since about 1995. Over this time I have set approximately 500 of these in 3/8" and 1/2" configurations. I also have a pull test setup, and have proof tested many in concrete (several in granite). Some of the benefits I have recognized are as follows:
1)Ease of removability- 100% removal of the bolt (including coil) is as simple as backing the threads out until the initial thread is engaged, then applying a prying force to the bolt with claw hammer or crow bar (protecting stone of course). The result is a clean hole, with no monkeying around with end cones or sleeves in the bore. I have done ground up routes using these, and during rappel outfitted with glue-ins during the same day.
2) Ease of inspection- As a direct result of #1, the bolt shank can be inspected in about 30 seconds, and is returned to service without any worry of cross threading due to the large thread pattern. During several cycles of removal and inspection of routes I have put these on, they appear to be weathering well, and showing minimal corrosion or degradation.
3) Strength- In granite, this anchor performs well with dynamic loads, freeze thaw ice wedging and subsequent nut loosening (wedge anchors prone to this around here), and is full diameter Grade 5 steel. In 1/2 " size, the shear goes up to about 23000 lbs for a 3" embed. relative strength approaches that of epoxy anchors for bore size.
4) Predictability- I have never had a spinner (during or long after install) when these are properly installed with a reasonably clean bore that is of appropriate depth. I feel that this setup is no more prone to failure than other systems when installed according to manufacturer's instructions. Let's face it- all anchors that could be called into service in this way need to be installed well and by qualified individuals. Grade 5 steel also corrodes in a relatively predicatable fashion. I am somewhat concerned that the current trend in our area of 3/8" SS wedgies will someday be a difficult to remove setup that may harbor undetected corrosion. We used to think buttonheads were the answer...
While there may be no perfect anchor for every situation, I think this one has many benefits that work well for higher compressive strength rock. In an attempt to minimize galvanic corrosion between SS hanger and HCA, I use a stiff nylon washer under the bolt head. This seems to help considerably.
I will be inspecting several routes soon, and will post pics if anyone is interested.
MH
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Off White
climber
Tenino, WA
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May 10, 2007 - 12:01am PT
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Mark - Have you used those bolts in the sandstone conglomerate on Big Four?
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Mark Hanna
climber
Seattle, WA
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May 10, 2007 - 12:13am PT
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Off-
Yes- they were used there, and will be replaced by glue-ins this summer, as this was a ground-up affair, and this is likely the wettest place around here. Have you done the route?
MH
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Off White
climber
Tenino, WA
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May 10, 2007 - 10:23am PT
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Not yet, but it's floating around in the tick list in the back of my head and occasionally surfaces like the fortune in a Magic 8 Ball. Odds are good I'll head there this summer, and in addition to the Tower direct I'd like to do the one on the peak proper, is that The Mule? They look like swell midsummer adventures.
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 10, 2007 - 10:38am PT
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Mark - wow, thanx for chiming in. I do like the look of those Hiltis and it's good to hear from someone who has actually used them. It's hard for me to get reasonable advice since I still place bolts on the lead and many times "one-handed".
One question - can you tap in the Hiliti to the 'set' point without a hammer? (with a small wrench or carabiner, say?)
I think I'm going to order some and try them anyway - I like the fact that they are easy to replace since they are not SS - same as the Taper Bolts by the way (Grade 5 steel with zinc coating/plating).
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Jingy
Social climber
Flatland, Ca
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May 10, 2007 - 10:39am PT
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JB - Question? What, exactly, do you need bolts for? Last I saw, you were doing just fine without'em.
Take it easy and keep climbing, bra!
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Howie
Trad climber
Calgary, Alberta
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May 10, 2007 - 10:52am PT
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Hi Mark.
Thanks for that great info. I sure its just what JB was looking for.
For me I'm not interested in placing bolts but very interested in how one know a bolt has been place well and how secure it is after a period of time. These bolts seem to answer that question. I for one would be very interested in any pictures showing bolts being placed and there condition after a substantial amount of time in the rock. I also think that your idea of a hard nylon washer to seperate SS from CS is good. Please post further info after you have investigated the older bolts you placed.
As a trad guy, who will of course clip a bolt if its there, how would I recognise these bolts you use over other CS bolts? Thanks again.
Howie.
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Mark Hanna
climber
Seattle, WA
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May 10, 2007 - 01:52pm PT
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JB- The HCA could probably be set to depth w/ less than a hammer. It should be noted that I set them a bit deeper than the mark. This is a result of experimenting with a torque wrench to make sure they are not overtightened. As these anchors were designed for mid strength concrete, the depth set mark correlates to the torque needed in this softer substrate. Set some samples in the specific rock of the area, and you will find the point at which they clamp the hanger and achieve proper torque. Having never set a USE Taper, perhaps a similar method is used. I also use a longer wrench than I do with wedgies.
OffW- Let me know if you are interested in going up to Big Four with me sometime- both the Mule and the Tower routes are great fun
Howie- I will certainly post some photos up and coming.
MH
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 11, 2007 - 11:08am PT
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Thanks Mark - The "set point" is also less with the Taper Bolt in granite but not by much. Is there a good online source for these Hiliti bolts?
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Mark Hanna
climber
Seattle, WA
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May 12, 2007 - 08:29pm PT
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JB- I have only purchased at the Hilti distibutors outlets. You may try online resources that cater to tilt up panel concrete construction, as this is their historical use (as temporary bracing/shoring). Let me know if you find something-
MH
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scott johnston
climber
mazama, wa
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May 13, 2007 - 12:37pm PT
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Here is a bit more info on the HCA bolts. I have placed over 200 of these anchors in the 3/8"x3" size in both granite and some really hard local stone that I believe is a metamorphized volcanic sort of like basalt (it dulls my bits much faster then granite). My experience with ease of placment, lack of corrosion and freeze/thaw issues mirrors that of Mark Hanna. I find these bolts much less of a pain than trying to fiddle all the parts of a standard Rawl 5 piece.
Bachar- I usually carry a 12" breaker bar with a 6 point 9/16" socket on it. With this I can set the torque pretty accurately and have at times used it to drive the bolt into the hole to the set depth. Not as easy as with a hammer but it can be made to work. Just be careful not to knock the socket off the breaker bar while hammering!
I agree with Mark that the set depth must be deeper for rock than concrete and it may take a bit of trial and error to arrive at the correct depth/torque ratio in your local rock.
Howie- The markings on the HCA bolt heads will allow you to tell them apart. Aside from the standard grade 5 markings of three radial lines there is a "CY" and a "D" forged into the head of the bolt. These seem to stand up well to hammering so should be legible.
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 13, 2007 - 12:49pm PT
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Scott - thanx, good info. Your set up is the same I use for Taper Bolts (a socket wrench).
Has anybody used these in sandstone? ...done any pullout tests in sandstone (or some other soft rock)???
I "tested" the Taper Bolt pullout in welded tuff out here in the Eastern Sierra once with my VW bus. We place a 3/8" x 2 5/8" Taper in an outcrop of welded tuff right next to the road and tied it off to my VW bus bumper with a rope. I accelerated forward and got jerked to a halt a few times before I stopped. Not totally scientific but the the bolt wouldn't even move. Welded tuff is pretty darn soft once you drill through the surface. We were fairly reassured after the test however....
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tenesmus
Trad climber
slc
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May 13, 2007 - 05:14pm PT
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So, its easy to replace the hilit coils and the tapers. Is it specifically the just hilti coil bolts? What about their other bolts? I know they have stainless options but the ones I saw were stud type and I heard they were hard to replace.
The rep at my hilit store says he can get a deal and all....
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TGT
Social climber
So Cal
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May 13, 2007 - 09:44pm PT
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Caviat,
I've only placed a hand full of bolts on climbs and those were all wedge anchor types but here are some observations from having placed or supervised/paid for the placing of thousands in construction applications.
Wedge anchors are the easiest for the unskilled to place to full strength and the cheapest for the strength developed and OSHPOD approved. All they need is a clean round hole (not the easiest thing to do with a hammer and a hand drill) and a torque wrench to avoid over tourqueing. Over torque will cause the substrate to fail and produce a "spinner" (almost impossible in granite with a normal length 9/16" box wrench)
Wedge anchors are next to impossible to remove without damage to the substrate and you should always over drill the hole so they can be driven flush if there's the slightest chance they're in the wrong place, (a construction issue but not a climbing one, a pocket under the bolt could allow for some unpredictable freeze thaw effects)
The stud provides the full shear and pull out strength that can be developed by the fastener size / grade /substrate.
Five piece anchors will develop the full strength of the substrate in softer materials, even soft red brick. The substrate will fail first if properly placed. They fail corosively more quickly because of all the parts and the strength is usualy significantly lower than the equivilent stud/hole size. for example, a five piece 3/8" anchor has a 5/16" 16 UNC bolt. It has only 10% more minor diameter area than a 1/4"- 20 bolt. Shear isn't an issue because the sleeve contributes too but tension and corrosion allowances are! Soft stuff like parts of Red Rocks or Zion, I think I'd rather see a nice fat 1/2" five piece and all being said all five piece anchors should be 1/2" or stainless if 3/8".
I Think John is on to something here with the taper bolts in hard rock. They are more expensive and less available so I never used them in construction applications. A lot of the flack about Taper bolts comes from one statisticly insignificant test. Idealy a group of about five or so bolters of a range of levels of experience would place a statisticly significant number of bolts that would then be tested to failure. I don't see that happening any time soon.
When it comes right down to it you are stuck with what's there. 60+ year old Rawl Nail or brand knew ASCA approved bolt you still have to make the move. Better to know what's gonna be there or not test them at all.
Isn't that the point of the whole endeavor?
Not falling?
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 13, 2007 - 10:21pm PT
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TGT is right man...I'm giving up all this bolt stuff and sticking to free soloing.
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TGT
Social climber
So Cal
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May 13, 2007 - 10:34pm PT
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Well, that's not quite what I meant ;-]
But every 1/4" incher that I ever climbed past held the draw and the rope just fine.
And, induced considered and careful movement in the process.
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NoRushNoMore
climber
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May 14, 2007 - 04:47am PT
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Mark, why grade 5 zink plated and not SS?
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 14, 2007 - 10:18am PT
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Norushnomore - Interesting....they self tap into the rock and seem to have a high tension rating (pullout). It seems curious that the shear strength isn't very great (???).
Anybody ever use these things?
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TGT
Social climber
So Cal
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May 14, 2007 - 10:23am PT
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I've used them in construction settings and in hard substrates, (old concrete) the setting torque is just short of what's required to shear them off!
They work fine in green concrete though. I'd never trust one in granite!
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Mark Hanna
climber
Seattle, WA
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May 14, 2007 - 07:09pm PT
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I have tried the Wedgebolts as well, in construction use. I definitely agree with the green concrete use. I stripped many out in cured concrete. In the assessment of the Powers tech rep, our local aggregate is very high compressive strength when compared to the national average. Recently, I was climbing at a fairly new area in Eastern WA where the sandstone is really soft, and observed these being used. I think some pull testing would be a good idea before I trusted them in anything but green concrete. It takes a specially sized bit as well.
It should be noted that while they are available in SS, the specific type (410) was chosen for it's ability to receive the thread cut. Corrosion resistance is less than that of 304SS, according to the GoogleGod.
http://www.powers.com/pdfs/mechanical/07246.pdf
MH
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Tom
Big Wall climber
San Luis Obispo CA
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May 15, 2007 - 04:19am PT
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Removing a stainless 5-piece Rawl Power Bolt is fairly easy.
How hard is it to remove those other bolts, when they need replacing?
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bachar
Trad climber
Mammoth Lakes, CA
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Topic Author's Reply - May 15, 2007 - 11:13am PT
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Taper Bolts are easy to replace - just unscrew them. I would probably redrill the hole deeper and put in the next size - a longer one with its own new sleeve. I think after you unscrew one and pull it out, you run the risk of getting too much dust in the original sleeve so it might not thread correctly if you replace it... just my opinion however. The expert at MKT Fastening (a climber by the way) thinks it's fine to replace as long as you blow out the hole before you do it.
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Greg Barnes
climber
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May 15, 2007 - 04:30pm PT
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Just back from Red Rocks, with elbow tendonitis...dang hand-drilling.
On the taper-bolt and coil-bolt front, can anyone post a picture of the Metolius bolt that had a similar design (but looked like a glue-in once placed)?
I've only tried to pull (as opposed to just unscrewing) one 3/8" taper-bolt, which was placed straight-down into flat rock on top of a formation at Benton Crags (the crag about 150yds right of Challenger rock). Errett Allen put those routes up, but all bolts were 1/4" except for this 3/8" taper-bolt at the 3-bolt anchor, so I'm not sure he placed it. Anyway, drove a thin pin under the hanger and the bolt started popping out right away - no harder that a standard 1/4" bolt. Clipped a funkness and pulled the bolt with not much effort. The full sleeve was still attached to the bolt, so I guess there are 2 possibilities: either this was a bolt that was torqued not enough to set well, but well enough to set the sleeve into the bolt - or this was a case like Raleigh reports where a properly torqued and seemingly good bolt pulls out pretty easily. This location would see a lot of freeze-thaw action, and the hole was placed perfectly to see water/ice pooling in the hole.
I've pulled maybe 75-100 of the 1/4" versions, they pull easily, but so do most any other 1/4". Probably only get the sleeve out with the bolt 10-20% of the time. They did appear to be stronger in shear than any other 1/4", and since the split-shaft bolts did sometimes crack near the split, they were probably the best 1/4" bolt for granite slabs.
As far as the best bolt - hard to say, there are lots of different bolts and many factors. But I think the basics are:
 all of the "top competitors" for best 3/8" bolt are way stronger than anything we'll subject them to climbing, and so arguments about ultimate load strength are kind of irrelevant.
therefore, the most important thing should be reliability and long-term wear.
5-pieces are very easy to install and reliable, and wear very well. However, they rust, and it's a pain to remove the sleeve and cone. Stainless 5-pieces are also easy to install and are reliable, but they will not wear too well if subjected to very heavy repeated loads (especially hauling & sport-dogging). Not sure if this is just stretching of the bolt, or unscrewing since the installation torque is really low. As many have seen on El Cap, they do loosen up pretty easily. They are the current standard bolt that the ASCA uses in hand-drilled good rock, but we use 1/2" if we can power drill (or hand-drilling medium quality rock at Red Rocks, etc). The other problem with 5-pieces is you can't install them one-handed.
stud bolts are strong and easily installed, but are not removable and can not be inspected. Unfortunately these are very common for new routes, and nearly always non-stainless. Stainless versions are the only ones that climbers should ever use, but even these will deteriorate over time and will not be replaceable in the same hole (unless we can power drill through the remnants of the old stainless?).
Fixe Triplex bolts are strong, you can place one-handed, and are easily removed, but are 12mm so they are a bit larger. If used with a 12mm hole hanger, use locktite so the nut doesn't loosen - once the nut is loose, you pull the bolt with a quickdraw. The perfect bolt for ground-up routes where you'll replace with glue-ins. The bolts are reusable as well.
Petzl Long-life are strong in good rock, easily placed one-handed, but are almost like glue-ins in that they are basically impossible to remove. The 12mm hole is pretty short.
I've never seen these Hilti coil anchors. They actually seem like a really good idea if they are as strong as advertised. Problem is they are not stainless, but if they are so easily removed & inspected, they might be a good option for high-traffic anchors where the stainless bolts are stretching and loosening up.
Taper bolts have the questionable reliabilty from the Raleigh tests, plus the simple fact that you can't hand-drill through the sleeve to use a longer one, just like you can't hand-drill through the old 3/8" Star-Dryvin sleeves. I don't like the idea of reusing the sleeve, especially if JB has reservations!
Another option for non-stainless removable bolts is the new really short 5-piece (I guess 4-piece now). These have no blue plastic compression ring, so it will always be easy to grab the sleeve top with pliers, and thus removal is straight-forward but a bit involved (unscrew bolt, remove hanger, screw bolt in a couple turns, tap in once with hammer to unseat the cone, unscrew bolt, remove sleeve with pliers, screw bolt back into cone with hanger, funk out cone).
It'd be good to hear some expert opinions on long-term fatigue on all of these bolt designs from repeated loading such as in hauling or dogging. Also on the long-term effects of freeze-thaw cycles. I think that a 3/8" removable/inspectable non-stainless bolt that holds up better to heavy loads would be a good idea for some high-use bolts where we can't power drill in some beefy 1/2".
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Larry
Trad climber
Bisbee
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Jun 22, 2007 - 11:30am PT
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Why don't you just use a torque wrench and tighten to the right specs. Worked for me with FIXE wedge bolts. (Had to e-mail Spain to get the right specs)
So what are the right specs for Fixe bolts -- all models, if you have them? Maybe I missed it somewhere in this thread.
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Matt M
Trad climber
Tacoma, WA (Temp in San Antonio for Yr)
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Aug 27, 2007 - 12:12am PT
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Digging up an old thread I know but I came across the Hilti HCA coil anchors discussed on here on ebay today - seemed liked a great deal.
100 HCA 3/8in by 2.25in for ~$25
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=320112622910
Coincidentally, Fixe is having a sale on 100 Plated hangers - so no galvanic issues.
100 bolts (2.25in) 100 hangers for ~$125 - that's pretty solid....
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Matt M
Trad climber
Tacoma, WA (Temp in San Antonio for Yr)
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Aug 27, 2007 - 11:51am PT
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Lock - That's exactly what I thought when I saw them. Look earlier in this post... Mark Hanna has a great write up on his experiences with them at his local climbing areas in WA (I think I've climbed on some of his routes actually). The spec sheet at the Hilti site makes these things look good too. Yeah, they're not stainless but if they're that easy to remove and check, I don't think that's a deal breaker in many areas because ease of replacement (seems almost as easy as changing hold in the gym)
I was hoping Mark would post those pictures (if he had them) of the condition of those bolts he was going to inspect.
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Ed Bannister
Mountain climber
Riverside, CA
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Aug 27, 2007 - 06:06pm PT
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JB,
never thought you had too much practice placing bolts...
remembering "The Kid" in the meadows.
Strength and security per dollar?
1/2" x 4 1/2" 5 piece rawl, grade 5 steel.
Even the 3/8" can sheer when overtorqued, and too many think tighter is better.
In lieu of stainless, I like a tiny vial of casting resin, to "paint" the washer and nut, then apply fine sand gathered from the bottom of the climb, whala! no rust, and undetectible from the ground with pretreated, precolored hangers.
Ed
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Euroford
Trad climber
chicago
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Aug 27, 2007 - 06:28pm PT
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"These bolts are routinely used by construction workers all over the world with incredibly safe results. Has anybody had any bad experiences with these things? Any failures? Difficulty placing them? Why the bad rap? "
our firm doesn't approve the use of these bolts. as others have mentioned, they have been shown to be too finiky for a tourqe value, thus having a large effect on the pullout strength.
the powers wedgebolts (yes, stupid name) have a core hardness strength (50-55 Rockwell) that is too high. this has lead to embrittlement problems and currently we do not approve them. powers is now testing a special run of bolts here in chicago with a core harness between 35-45 and we've used them with good results.
i think they would be difficult if not imposable to install in hard rock. but i bet they would be AWSOME in sandstone. the pullout strengths are very good due to the huge contact surface across all of the threads.
i prefer the use of the powers powerstud in stainless steel for both high rise construction and recreational bolting.
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Euroford
Trad climber
chicago
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Aug 27, 2007 - 06:32pm PT
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FYI: those powers wedgebolts are not standard size. they need to be used powers drill bits designed for the bolt. thats why they have the blue tip, powers wedgebolt drill bits also have a blue tip.
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rick d
Social climber
tucson, az
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Aug 27, 2007 - 06:40pm PT
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wow, all these "lifetime" bolt threads.
20-25 years should be outside on any hardware. The easier to replace the better - if on a trade route. The others few will ever see and they will hold when you need them (except Spider Rock's rap bolts- yeeeeessssshhhh).
The strongest bolts need to be the ones to keep you off the deck/ledge. the ones in between, are "fluff".
Glue ins might not as long as you think and those Star Dryvin's Kor planted in 1960 will do for the A.0 moves.
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Kevster
Trad climber
Evergreen, CO
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Aug 28, 2007 - 01:01am PT
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Nothing beats the Petzl Long life for bolting on lead in solid stone. No wrench, no hastle. Have your draw clipped to the bolt, insert bolt in hole, pound in driftpin, clip and go.
I agree with KS that I wouldn't use these in roofs or super steep rock though.
My second favorite bolt is for drilling on lead is the Fixe Triplex. Hammer in the bolt and it is usually already bomber, a few turns with the wrench and your good to go. Replaceable, removable and everything important to inspect is on the outside of the hole. Once you have seen these bolts and placed a few you know they are going to outlast anything else besides a glue in.
Of course both of these bolts use 12mm holes so hand drilling in hard stone can take a bit longer. I really like the Hilti double fluted shorty drillbit as it cuts through granite like butter (exageration), and even has a red mark to let you know you have gotten the hole deep enough.
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