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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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Tradmanclimbs,
yes, I agree. If the drill bit gets worn, it gets too narrow. What happens with a Rawl 5-piece is that the cone on the end of the bolt gets compressed too much and when you try to tighten the bolt it just stop and the cone starts spinning in the hole.
The big lesson here is to replace worn drill bits!
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two-shoes
Trad climber
Auberry, CA
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Get on some chossy rock and that same worn out drill bit will drill the hole oversized too.
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tradmanclimbs
Ice climber
Pomfert VT
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two shoes/ Fixe? what is your take on the rawl power wedge loosening up and the sparp angle of the cone on that bolt? And the fact that they do not rate it for stone?
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Greg Barnes
climber
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Topic Author's Reply - Apr 5, 2015 - 07:48am PT
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Here's an old and a new (cone textured) stainless power-stud. Old from early 2000s? New from 3 or 4 years ago? The old is a 304ss while the new is 316ss, so I don't know if there were differences between metal types.
The new generally "looks" weaker since the sleeve is thin and moves around a lot. However I tried to over-torque a couple in a test rock and they didn't break easily - in fact I had difficulty breaking them by over-torquing even when I really cranked (bolt must be stretching).
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Dimes
Social climber
Retired from Everything
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Here is something I have not seen before in Josh. A "carrot" as they were called in Australia back in the 90's. Removed this week out at Echo Rock. There was no hanger on it, but you could have cinched the cable from a wired stopper around it. Once again, you just cannot tell by looking at the outer, exposed part what is behind it.
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crunch
Social climber
CO
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I think when the bit gets worn out with the bosch it drills too tight a hole.
That's when the holes are just about perfect for the soft rock I usually drill into.
Soft rock ideal is a slightly worn drill, tight hole, Powers 5-Piece.
Another trick (again, soft rock only) is to snug up the sleeve onto the cone, just a tad, so it's visibly riding up the cone a bit and just barely touching the rock, before tapping it into place. Recheck this a couple times while drilling (while hammering, the parts try to shake loose). Seems if the sleeve is scraping on the rock it forms a slight groove/scratch down the hole and thus resists spinning once the bolt is all the way in and being tightened up. YMMV...
EDIT: Dimes, that "carrot" is classic!
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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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Greg Barnes wrote:
The new generally "looks" weaker since the sleeve is thin and moves around a lot. However I tried to over-torque a couple in a test rock and they didn't break easily - in fact I had difficulty breaking them by over-torquing even when I really cranked (bolt must be stretching).
When I have broken these by over tightening them they shear off at the top of the cone where the diameter of the bolt is the thinnest. In looking at the photo you provided it seems like one of the advantages of having a thinner sleeve with the new bolt is that the diameter where the cone necks down is slightly greater. That might be the reason it was hard for you to break the new design.
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two-shoes
Trad climber
Auberry, CA
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Greg,
Here is some stuff I found out:
There are over 150 types of Stainless Steel. Mostly only about 15 types are ever used.
304 SS will tarnish only very superficially over a long period of time, unless it is in a highly corrosive environment, such as the sea coast. 304 is suppose to have a little better structural advantages and durability from working than other grades. 304 SS also known as 18/18 and is the most widely used of about the 6 most used stainless steels. It is composed roughly of 18% chromium 8% nickel
316 SS will stand up to a much greater amount of corrosion, and will still corrode at the sea coast. It is composed roughly of 16% chromium 10% nickel 2% molybdenum.
All 200-300 series SS is made of an annealed austenite structure of iron and is non-magnetic, but work hardening can make austenitic iron slightly magnetic
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two-shoes
Trad climber
Auberry, CA
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tradesmanclimbs,
One thing I didn't get is the Rawl Power Wedge, a steel bolt or, stainless steel?
If it isn't rated for stone, then It probably wasn't designed for hard stone at least. Maybe it has a hard time grabbing the hard polished stone? Is it in granite? Is the stone harder than usually, or softer than usual? What about the drill that was used, was it a new drill, or a worn out drill? Just trying to think of different factors that could change the variant enough to cause this malfunction of the mechanism.
If they are steel bolts then the sliding sleeve could be rusted to the cone part, and it could be a real problem to get to slide up the sleeve and get it to grab hold of the rock again.
I've seen this happen to a few True Bolt wedges that were 304 SS. They had become loose and the hangers were spinning. Folks tried to tighten them up and they weren't really grabbing to any real extent. Now there is some dangerous length of threads protruding from the rock. I'm going to try to remember to take my hammer and wrench next time to see if I can reset the darn things at a deeper depth. I'm not sure what happened in the these few instances? Wondering if maybe they were a little over tightened from the git-go? This is a really icy little gorge in the Winter and was wondering if water could have gotten in back of the hole and did some frost-wedge-hydraulic-jacking of the bolt itself?
Anybody have any ideas?
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Greg Barnes
climber
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Topic Author's Reply - Apr 5, 2015 - 01:34pm PT
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Sorry, wrote that poorly. I know a lot about the differences between 304 and 316, what I was trying to say that since Powers made the Power-Stud in both 304 and 316 with each generation of bolt, but I only have a sample of 304 from the older generation and 316 from the newer, there's a chance that the design varied slightly between metal types for each generation. Probably not significant, but on the other hand you never know.
There are a million other sleeve bolts, this is just one manufacturer, and a lot of them look very sketchy (often bought at the local hardware store). Some of the cheapo ones look like the sleeve will fall off just for the heck of it...
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Juan Maderita
Trad climber
"OBcean" San Diego, CA
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two-shoes,
It is likely a "red herring" to try to identify if a bolt is "rated for stone" or "designed for stone" per the manufacturer (unless discussing climbing-specific manufacturers, such as, Petzl, Raumer, Fixe).
Powers, ITW Ramset/Redhead, Hilti, Confast, etc. design and manufacture their mechanical anchors for the construction industry. They are rating their bolts for concrete, hollow block, etc. They have no interest in stone. Probably less than 1/10th of 1% are installed in stone. Recommending for stone, with all of stone's variability/unpredictability would open them up for liability. Almost certainly, these manufacturers want to distance themselves from their bolts being used or approved for climbing purposes.
So, if you don't see a mechanical anchor "rated" or "designed" for stone, that only means that the manufacturer is intelligent enough to not publish any info.
Climbers are using these products "off-label", to borrow from pharmaceutical terminology.
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pyro
Big Wall climber
Calabasas
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brand new!
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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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^^^^^^
And they should stay that way!
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Juan Maderita
Trad climber
"OBcean" San Diego, CA
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I suspect that some/most wedge anchors which spin or fail to achieve torque quickly (4-5 turns), may be the result of debris in the hole.
At a minimum, the hole should be cleaned by blow, brush, blow, brush, and a final blow. (Assuming hard rock. The expansion force on the small surface area of the collar is tremedous and can crush softer rock inside the hole.)
25+ years ago, I was power drilling 5/16" buttonheads. Seemed like a huge upgrade from 1/4" at the time. Blowing the hole clean seemed good enough, and perhaps it was, for a Rawl (now Powers) "Drive" contraction bolt.
Around 1990, I switched to 3/8" Ramset/Redhead "TruBolt" SS wedge anchors. It took a while to realize that adding a brushing to the cleaning procedure removed much more debris. Still later, I discovered that alternating multiple brushings and blowings was necessary.
There is another wedge anchor installation problem, which I've encountered 2 or 3 times (out of hundreds). The expansion collar can get pushed above the cone and onto the shaft of the bolt. This can happen with the first few taps of the hammer, as the bolt enters the hole. The collar catches on the outer edge of the hole, expands slightly, and rides up over the ridge onto the shaft. This results in a botched placement, as the anchor will fail to achieve proper torque. Now I have learned to visually watch the bolt enter the hole for the first few hammer taps.
I'm currently installing 1/2" Hilti KB3 SS wedge anchors for belay/rap anchors. Luckily, in Baja there are no regulations about power drilling. A 1/2" x 4" hole takes one minute.
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two-shoes
Trad climber
Auberry, CA
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Juan Maderita,
Yeah, I'm sure you're right about that. I hadn't really thought about that. I know that construction workers do fire bolts occasionally into real rock, as well as backcountry installations by forest service, PGE, SCE, etc.
I remember hearing 25 years ago from a guy by the name of Phillip, who owned the Lucky brand U.S. distributorship, that Fixe bolts were made in Spain, just as Lucky bolts were, and used the same machinery that was in no way different than any other industrial construction bolt machinery. You could say all of these bolts are designed for rock, if you wanted to suffer the liability perhaps. Because, is there really any basic differences in any structure, or mechanics, of the bolts, whether they are construction grade or "made for climbing" grade, do you think? I would guess that they are basically the same.
I know the distributorship that we buy SS wedge bolts from in the greater Fresno area, sells most of these 3/8" x 2 1/4" bolts to climbers. I know because he invited me back to his office and acknowledge the fact in just so many words. For one thing, he knew that I wasn't your typical looking "jobber", so to speak. And another thing was he came back with at least a couple different models of Bosch battery operated rotary hammers, and a Panasonic that he thought that I might be game in purchasing! He does give us climbers what I think is a wholesale price, these guys like selling volume business.
Me and my buddies most always at least blow the holes out, unless we are just way too gripped! Maybe we should be brushing them, too? I've climbed with at least one person before, on many occasions, who doesn't believe in blowing the holes out. It is totally against my every fiber to not blow the hole out! But, I've watched him just drill many, many holes just extra deep and not blow the hole out at all! I haven't seen any problem with the initial installations, as of yet anyway.
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tradmanclimbs
Ice climber
Pomfert VT
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certainly looks to me as though i am not the only one who had the collar pop off the cone. Otherwise they would not have stippled the cone.
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tradmanclimbs
Ice climber
Pomfert VT
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Stainless steel. thought that would be obvious by the part number 07312 I guess you have to add the smaller numbers so Powers 07312 304 ss
No recolection on age of drill bit but some were hand drilled, some power drilled. some in hard granit, some in softer shist. Shitty desighn INMOP with the very sharp angle of the cone. the bolt initialy tightened fine but after being loaded in falls or jerky rapelling the collar popped off the cone and the bolt became visibly loose to the point that it could be pulled 2/3rds of the way out of the hole with finger pressure/ no tools. Super effing scary!
Whomever said they don't rate for stone is talking out their ass. Redhead Truebolt WW-3830 rated for stone and concrete. they have annother wedge bolt that looks identicle to the powers bolts that failed that was rated for concrete only.
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Juan Maderita
Trad climber
"OBcean" San Diego, CA
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two-shoes,
Absolutely, the hole should be thoroughly cleaned of dust and debris before installing a wedge anchor. Every manufacturer and knowledgeable source will state that. You will be amazed at how much crap comes out with brushing, even after you thought the hole was blown clean. I'm amazed at how much more is removed with a second brushing!
Better to risk a fall than botch a bolt placement. Lives depend on the first ascenionist installing bolts correctly.
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tradmanclimbs
Ice climber
Pomfert VT
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I brush 3 or 4 times in between the blow tube. No it is not worth takeing a bad fall though. If its too scetchy don't get hurt. get something in and then go back and fix it on rapell if you feel it needs fixing.
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Juan Maderita
Trad climber
"OBcean" San Diego, CA
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Whomever said they don't rate for stone is talking out their ass. tradman,
I'd like to see your evidence that any of the major manufacturers of wedge anchors (Powers, ITW Ramset/Redhead, Hilti, Confast) rates or recommends their product for stone.
I'm backing up my statements with this info quoted from their websites and spec sheets:
ITW Redhead "Trubolt"
"SPECIFIED FOR ANCHORAGE INTO CONCRETE"
and "Anchors for Concrete Applications"
Hilti Kwik Bolt 3 (aka KB3)
"Base materials: Concrete (light weight), Concrete (uncracked), Masonry (grout-filled CMU)"
"Approved by ICC-ES for use in masonry and concrete"
Hilti Kwik Bolt TZ
"ase materials: Concrete (cracked), Concrete (light weight), Concrete (light weight over metal deck), Concrete (uncracked)"
Confast "ThunderStud"
"A wedge anchor is a type of fastener designed to be installed into solid concrete." "Applications: Light to heavy-duty into solid concrete."
Powers has several slightly different wedge anchors. I saw no reference to stone as a base material.
Powers "Power Stud"
"The Power-Stud anchor, is a fully threaded, torque-controlled, wedge expansion anchor. It is available in a threaded version suitable for applications in solid concrete and grout-filled concrete masonry"
Powers "Power Stud" SD2
"The Power-Stud+ SD2 anchor is a fully threaded, torque-controlled, wedge expansion anchor which is designed for consistent performance in cracked and uncracked concrete. Suitable base materials include normal-weight concrete, sand-lightweight concrete and concrete over steel deck."
The only reference that I found about stone was describing the attachment of stone to buildings in the construction industry. http://www.itwredhead.com/pdfs/RH_pdfs/RH_cat_021212.pdf
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