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ß Î Ø T Ç H
Boulder climber
extraordinaire
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Mar 25, 2015 - 10:35pm PT
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Rust in peace.
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Roger Brown
climber
Oceano, California
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Mar 26, 2015 - 07:47am PT
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13-15 foot pounds is not much pull with a 12" long wrench. That same 12-15 foot pounds is a pretty firm pull with a 4" wrench. Spot checking with a torque wrench is a good idea.
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Tork
climber
Yosemite
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Mar 26, 2015 - 08:25am PT
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D2RE2 you just love to hate, don't you?
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two-shoes
Trad climber
Auberry, CA
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Mar 26, 2015 - 09:10am PT
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Hey guys, have another look at Dimes bolt and hanger, because that's not a, so called, 5 piece 1/2" bolt, but a 3/8" screw with a thin sleeve, at least I think?
What I'm talking about, in my previous post, is a 5/16" screw in a thin sleeve that needs a hole drilled for it of 3/8". The hanger rests on 5/16" screw stock, and thin sheet metal sleeve. How strong could this possibly be?
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guyman
Social climber
Moorpark, CA.
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Mar 26, 2015 - 09:12am PT
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If one is trying to figure out if you have stainless steel, the magnet is not the way.
To best figure out if something is stainless, you need to use "gun blueing", pick up a tube at your local gun store.... dab on a bit, if it turns dark..... you don't have stainless.
After almost 30 years in the Ball Bearing industry that was one of the tools I use, mostly when dealing with unmarked miniature ball bearings.
This is a really good thread, thinking about this is very important subject is key to our future safety.
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Brian
climber
California
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Mar 26, 2015 - 11:14am PT
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Those last photos by Dimes are deeply, deeply disturbing.
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Greg Barnes
climber
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Topic Author's Reply - Mar 26, 2015 - 11:49am PT
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That's not a 5-piece, it's a 3/8" Lok-bolt type design. These are super weak, barely better than a 1/4" button head.
http://www.powers.com/product_06160.php
The ultimate strength is only 2440 lbs shear/2700 lbs tension. Compare that to 2090 lbs shear for a 1/4" button head (1760 tension).
Unfortunately those are found somewhat often.
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HighTraverse
Trad climber
Bay Area
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Mar 26, 2015 - 02:18pm PT
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From the Powers bolt Greg referenced above:
Door and Window Frame Installations
• Mounting fixtures on walls
• Mounting of Handrails and Fencing
• Shelving and Storage
• Masonry Applications
• Electrical and Mechanical Attachments
my NOTE: not recommended for any structural/high strength use
Now the Power-Stud SD1
Structural connections, i.e., beam and column anchorage
• Safety-related attachments
• Interior applications / low level corrosion environment
• Tension zone applications, i.e., cable trays and strut, pipe supports, fire sprinklers • Seismic and wind loading
Which one would you trust after it's been in place 10 years?
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Roger Brown
climber
Oceano, California
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Mar 26, 2015 - 02:30pm PT
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D2R2,
I also use a 4" wrench and a firm 3 finger pull, just on the shaft puts me right on. I think it would be difficult to do any real damage if you don't let your hand get out over the end. A 7" gear wrench can produce a tremendous amount of torque.
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Oso Flaco
Gym climber
Atascadero, CA
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Mar 26, 2015 - 06:36pm PT
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Regarding torquing anchor bolts:
I don't know for certain what the consequences are of under-torquing or over-torquing anchors, but I assume that under-torquing might create a weaker than desired "frictional adhesion" in the anchor and that it may be more prone to loosening. Over-torquing can obviously damage or destroy the bolt or if not that, maybe cause extra stress that could lead to corrosion. There were some posts earlier in the thread talking about stress corrosion cracking.
I think the best answer to whether or not a torque wrench should be used when installing bolts is, yes, it should be used.
Manufacturers place torquing specifications on the technical data sheets for their anchors and probably for good reason, so the bolt's performance is close to what they've specified in their data sheet.
I know torque wrenches are heavier and more expensive than an adjustable wrench or box-end wrench and they also require the proper socket, but consider it a good investment into a job well done rather than being cheap (don't wanna pony up the $25-30) and lazy (don't feel like carrying a few extra ounces). If the extra ounces deter us from packing it in for a long approach, then we should at least be calibrating our "pull" with the wrench we will be using so that we are close to the manufacturer specified torque.
They are another fun tool to use, and think about how good it feels to know you've done the best job possible in installing that new life-supporting hardware, both for yourself and for the others to follow. If people use them for building and structural applications, how much more should we be using them for our life-supporting anchors? Especially given that your health or life, as well as others, is often dependent on only a single one when leading off the ground or above a ledge.
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Oso Flaco
Gym climber
Atascadero, CA
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Mar 26, 2015 - 07:01pm PT
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Given the cost of using higher grades of stainless such as those JimT mentioned above, I think it would be better to look at using titanium at that point. If that high grade SS wedge anchor really costs $30, titanium would be more affordable at that point and likely much more corrosion resistant. There is a company based out of the UK, called Titan I think, producing titanium glue-in anchors and other anchor hardware. Last I checked I think their bolts were selling for $10-12 a piece plus the shipping from the UK. That seems like a reasonable cost for something that will last a very very long time. Also, I've seen mechanical titanium anchors (hanger & bolt) on eBay, made by a company called Keith, that go for about $32 for a hanger/bolt set if my memory is close. They are a wedge type anchor, so not easily removed, granted it would be a very long time until they would need to be. I think removability over corrosion resistance is favorable for most climbing areas that will have people putting in time for checking and replacing them. For unmaintained areas and sea cliffs I think corrosion resistance is more important. But why not have both?
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Clint Cummins
Trad climber
SF Bay area, CA
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Mar 26, 2015 - 07:25pm PT
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My partner cragnshag has been using 316 stainless wedge bolts for several years now - all our routes have them. At $2.50 or so each (before hanger), they are not much more expensive than 304 ($1 or so each last time I checked). My guess is that they are good for 200 years in good granite.
A torque wrench is not needed for every placement, if you use a short wrench like Roger has described, and you calibrate the force on your fingers with the short wrench against a regular torque wrench occasionally.
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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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Mar 26, 2015 - 09:59pm PT
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As far as proper toque is concerned, for those of you who use Powers 5-piece SS bolts there is a grey, plastic washer between the bolt head and the washer which is designed to indicate proper torque. As you tighten the bolt, the grey washer gets squished. Stop tightening when it is visible from underneath the bolt head.
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MisterE
Gym climber
Bishop, CA
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Mar 26, 2015 - 10:14pm PT
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A torque wrench is not needed for every placement, if you use a short wrench like Roger has described, and you calibrate the force on your fingers with the short wrench against a regular torque wrench occasionally.
In mechanic terms Clint, the "calibration" is as follows:
Finger tight
hand tight
wrist tight
elbow tight
arm tight
shoulder tight
back tight
and body tight.
Your results may vary.
%^)
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JimT
climber
Munich
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Mar 27, 2015 - 02:47am PT
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My partner cragnshag has been using 316 stainless wedge bolts for several years now - all our routes have them. At $2.50 or so each (before hanger), they are not much more expensive than 304 ($1 or so each last time I checked). My guess is that they are good for 200 years in good granite.
A torque wrench is not needed for every placement, if you use a short wrench like Roger has described, and you calibrate the force on your fingers with the short wrench against a regular torque wrench occasionally.
Specifically with wedge bolts the torque is practically irrelevant. We have done a fair bit of testing on them and the strength/pull-out resistance doesn´t change whether they are torqued correctly, torqued and loosened or never tightened at all (in fact the strongest ones were never tightened but the difference is minimal.
The reason for the manufacturers torque specification for wedge bolts is the are classified as torque controlled anchors and the force applied by the correct torque ensures the anchor will hold its specified load. This saves pull testing on site.
For a M10 316ss wedge bolt ultimate failure is at 117Nm/86ft.lbs and the usual over-torqueing failure is at 92Nm/68ft.lbs when the small tabs on the clip shear off (this is when the bolt goes `soft´and starts to spin. This is designed in by the manufacturers so you can´t break or weaken the bolt by overtorquing at least according to our manufacturer who should know.
Typically these torque numbers are impossible with a normal spanner, however not all 316 bolts are equal, machined thread bolts are notoriously weak.
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Roger Brown
climber
Oceano, California
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Mar 27, 2015 - 06:57am PT
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Jim,
With 3/8" 5-piece stainless, if the hole is drilled properly, how many turns should it take to tighten a bolt? When the bolt starts going in hard and I can no longer get three turns I change bits. What do you think? I value your opinion.
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two-shoes
Trad climber
Auberry, CA
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Mar 27, 2015 - 08:30am PT
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Greg Barnes, thanks for the info on the lok-bolt! I was pretty sure that these were really weak.
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two-shoes
Trad climber
Auberry, CA
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Mar 27, 2015 - 09:18am PT
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Has anyone ever seen a steel 1/4" bolt that was or maybe still is being made by Rawl? I can't remember the name of this model of bolt, but the bolt is a single piece, looks like a big nail head, is 1 1/2" long and instead of using a split it has a crooked section in it's stem that jogs over at about 1' deep and then back in line again. This is a contraction bolt and driven in like a Rawl Drive. I once, nearly 25 years ago, experimented with these. I thought they were fairly strong, I think that they were suppose to be stronger than a Rawl-Drive on their specs. sheet. I put up a single pitch face climb with a Bosch. It went well. I think I had taken one short fall on the lead. I was going to come back and re-bolt the route the following weekend with 3/8" bolts. But when I came back to re-lead the route every single one of these S.O.B. mothers were snapped at the crook and would slide right out of the rock into your hand! I was totally wigged out, and totally pissed. At the first bolt, I had to try to down climb in a puckered state of mind. I had to re-lead the climb with the Bosch in tow all over again, and then patch all of these holes because of the locked piece of metal in the back of the holes. I called Rawl about it, and I told them that I was using them in granite (not telling them about the rock climbing!). They told me that they were designed for concrete only! I think the holes were tighter in hard rock than concrete. When you hammer a Rawl- Drive into concrete the bolt kind of tears its way into the concrete. Probably the same with this bolt, too. These apparently got way to stressed and then just snapped on their own. It was probably one of the stupidest ideas that I have ever had and could have cost me my life for sure!
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HighTraverse
Trad climber
Bay Area
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Mar 27, 2015 - 09:46am PT
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and could have cost me my life for sure! or the next guy's life. Good for you catching the problem and re-bolting.
I've always been suspicious of the split/bent bolts. The large amount of metal deformation can't possibly be a good thing. Convenient for putting broom hangers in your basement wall maybe.
Caveat Emptor
My comments on this thread are from my experience as a climber and as an equipment design engineer largely in the pharmaceutical equipment industry.
I've only drilled and placed one bolt on a route a friend was putting up on Hogsback at the Leap. It was so long ago I don't remember what sort of bolt. I was early in my career and understood little about the practical applications of steels.
I suspect that in 1976 bolts themselves were less specialized than now.
end Caveat
I'm learning a lot from this thread.
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Big Mike
Trad climber
BC
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Mar 27, 2015 - 10:00am PT
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What route did you drill the bolt on Fred?
Jimt thanks for sharing your knowledge. It's stuff like that that keeps me coming back.
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