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 Post subject: lose bolt at bronkies
PostPosted: Mon Sep 13, 2010 10:29 am 
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Joined: Mon Sep 13, 2010 10:23 am
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Real Name: Charlie van der merwe
The bolt in the roof of the route called PMS at bronkies moves around and is difnately not safe. What is the correct procedure to follow who should be informed ?


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PostPosted: Mon Sep 13, 2010 2:12 pm 
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Joined: Thu Aug 28, 2008 4:34 pm
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Charlie101

Is the “Bolt” loose or is it just the nut that is loose? I find it hard to be leave that a “bolt” in a roof can move around and not fall out. If it is just the nut then you should have reached into you pack and pulled out the size 17 spanner that as a sport climber you should carry. Make the nut finger tight then add an 8th of a turn. Don’t try and crank the hell out of it that bad for the “bolt”.

If in fact as you say the rout is “definitely not safe” then the onus is on you to mark the rout as unsafe and give a reason why. Mark it clearly! Put some tape through the first hanger and write on it what is wrong with the route in this case you should have put a cross over the “definitely not safe” “bolt” in tape too. It is your responsibility to other climbers to do this. If you really think a route is unsafe and you don’t mark the route then it’s on you if some gets hurt climbing it.

Getting back to what is actually the problem here. Do you know what a “bolt” is? In general, in the Gauteng area “bolts” consist of a Hilti HSA stainless steel anchor, a hanger, a washer and a nut. As this is a system that you trust your life to, I suggest all sport climber find out how it works. Then next time you come across a problem you can be able to diagnose it correctly and hopefully fix it yourself.

When you are at Bronkies or most other crags remember you are on private property doing a private sport at your own risk and most likely if you get hurt your medical aid will not cover you. Your only real safety net is the community of climbers around you. You did the right thing by being vigilant to what is going on around you, but you need to be more proactive in evaluating the state of the fixed protection you’re using and notifying your fellow climber about risks. You also need to take ownership of the routs at your local crag and not just expect to notify someone and have then come fix it for you.


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PostPosted: Mon Sep 13, 2010 5:26 pm 
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Joined: Mon Sep 13, 2010 10:23 am
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Real Name: Charlie van der merwe
I know what a bolt is and the difference between a bolt and a nut. The BOLT is lose and moves around. I tried to yank it out so that nobody can clip into it but didnt get it out, This does not mean it wont come out if you fall on it! I scratched on the rock at the start of the route Danger Lose bolt but also understand that after the first rains this will be gone and that is why I am trying to find out how to fix the problem permanently! I dont know the first thing about bolting but, instead of just critsism you could put me in touch with the correct person and I will be super amped to go out there and fix it.


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PostPosted: Tue Sep 14, 2010 8:15 am 
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Joined: Mon May 28, 2007 4:30 pm
Posts: 22
Real Name: Gary Coleman
@GregB

WOW, i wish i could help people out like you! charlie101 asked a qeustion and you get all "do you know what a bolt is" righteous on him. He did what he could by posting it (NOTE: new member, 2 posts, so he went trough the effort of registering)and asking for help, and that is the reply.......

thumbs up dude, your a winner....


Last edited by gator on Tue Sep 14, 2010 1:42 pm, edited 1 time in total.

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PostPosted: Tue Sep 14, 2010 10:03 am 
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Joined: Wed Aug 15, 2007 8:22 am
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Location: Johannesburg, Krugersdorp
Real Name: David Tapp
Charlie,

I'm going to be bolting at Bronkies sometime in the next month or so and I can replace it then.
Obviously, if someone can do it sooner, all the better.

If you don't get any better offers I'll check it out when I'm next there.
In the meantime, if you go back and would do this great public service, please put a large and waterproof marker on the lowest hanger to explain the situation.

and please, if anyone does sort out this bolt, will you post on this thread so I and anyone else will know not to bother. Thanks very much.

:thumleft:

Cheers,

Dave


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PostPosted: Tue Sep 14, 2010 12:15 pm 
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Joined: Wed May 04, 2005 7:25 am
Posts: 229
Location: Cape Town
Real Name: Russell Warren
Express anchors do not normally come loose by themselves unless there is a problem with the rock in which they are placed. You will probably find that if you want to put the bolt close to the original then you will have the same problem a bit later unless you use a glue in. An important point to note is that just because most of the rock on the route is sound for express anchors, does not mean that the entire route's rock is good enough. I have bolted a 10 bolt route that required 1 glue in and recently bolted a route that had 4 express anchors and 5 glue ins. It is very important to use a torque wrench to torque the express anchor to 30N.m. to set it properly. Normally if there is a rock quality problem the anchor won't set properly.


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PostPosted: Tue Sep 14, 2010 12:38 pm 
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Joined: Fri Jun 27, 2008 8:38 am
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Location: Port Elizabeth
Real Name: Derek Marshall
Torque to 30N to set the collar, then totaly untighten the nut. Re-tighten the nut to 10-15N. Rather a loose hanger than a bolt left under high tension.


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PostPosted: Tue Sep 14, 2010 10:06 pm 
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Location: Rustenburg
Real Name: Marc Dewrance
Would it be neccessary to loosen the nut on a glue-in anchor?
Would the same rules about over tightening the nut apply there?


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PostPosted: Tue Sep 14, 2010 11:02 pm 
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The glue-ins used (and I assume the ones implied) don't have nuts. They are a solid metal bar bent and welded to form a ring or loop. No moving parts.

Some examples below.


Attachments:
rings.jpg
rings.jpg [ 12.83 KiB | Viewed 1534 times ]

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PostPosted: Wed Sep 15, 2010 6:45 am 
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Location: Cape Town
Real Name: Russell Warren
I have used the 10mm 316 threaded bar glue-ins which indeed do use a stanard hangar and washer arrangment like the express anchor, but then you torque the nut to 20N.m. as per the manufacturers recommendation. This arrangment is a lot more economical than the ones Mullet refers to and also easier to obtain. NB if you are going to use glue please find somebody that has done it before and knows what he/she is doing to guide you through the process. There are several ARF bolters with plenty of glue in experience. The margin for error with a glue in is much smaller than with express anchors. That said the glue in if done properly is the bees bollocks!


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PostPosted: Wed Sep 15, 2010 7:57 am 
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Location: Johannesburg, Krugersdorp
Real Name: David Tapp
mmmm......

it's potential-pun-city here!

I want to talk about torque!

and also mixed-metaphor-ville.........if glue-ins are the bee's bollocks, what are the dog's knees?

But I digress!

Re: torque for Hilti 10mm expansion bolts

The correct torque is 30Nm as we have agreed above.

So I took my (heavy and cumbersome) torque wrench with me bolting one day and was amazed to find how little force is needed to tighten a bolt to that torque. I reckon most people wouldn't believe/trust that it's tight enough at that torque, hence the widespread practice of over-tightening!

OK, so how do you set your expansion bolts to the correct torque?

Do you
A -- take a torque wrench,
B -- learn what 30 Nm feels like
C -- or have you found some small and light setting tool?

I'd love to set my bolts to the correct torque but I'm not gonna take a torque wrench and I know for sure that i tighten them to greater than 30Nm.

And also....when have you ever seen a crater-shaped defect in any sort of hard rock where the tension set up in the over-tightened bolt has caused failure?
I haven't seen one in 20 years of sport climbing, so I reckon there's enormous latitude for tightening bolts.

Nevertheless I'd like to do it right, so any ideas??

Cheers,

Dave


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PostPosted: Wed Sep 15, 2010 9:11 am 
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Location: Cape Town
Real Name: Ernesto Ismail
It really is amazing how easy it is to over-tighten fasteners. One can buy several fairly small "deflection" style torque wrenches. It you only intend on tightening to one particular torque you can make one yourself quite easily too.

Also, with strain gauges and some simple circuitry you can make a digital one.

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PostPosted: Wed Sep 15, 2010 11:26 am 
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Location: Cape Town
Real Name: Russell Warren
At Tapster.

Over torquing is not about the rock failing, it is about unecesarily high stresses in the bolt which then leads to what is called stress corrosion cracking.

My suggestion is that if you take the time and trouble to bolt a route you should do it properly and use a torque wrench every time. I bought a torque wrench and after using it I became aware that I for one had been guilty of grossly over torquing the bolts.

If a bolted route is torqued properly I believe it will have a near to infinite life expectancy.

I want to restress again if you are going to bolt do it properly.


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PostPosted: Tue Nov 02, 2010 8:25 pm 
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Joined: Wed Aug 15, 2007 8:22 am
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Location: Johannesburg, Krugersdorp
Real Name: David Tapp
I've been out of action for weeks, after a stay in hospital and so I haven't been able to get to Bronkies to sort out the PMS bolt.
Does anyone know............Is it still loose? Has it been fixed??


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PostPosted: Wed Nov 03, 2010 8:23 am 
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Joined: Tue Aug 22, 2006 1:42 pm
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The old bolt under the roof has been removed and a new one just over the lip has been placed courtesy of Ken Thrash


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PostPosted: Wed Nov 03, 2010 6:09 pm 
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Location: Johannesburg, Krugersdorp
Real Name: David Tapp
Most excellent!

Thanks Oubaas.

:thumright :thumleft:


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