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 Post subject: Rebolting
PostPosted: Fri Apr 29, 2005 10:57 pm 
It's good to see the efforts being made by the MCSA to rebolt old routes, especially in the light of the Silvermine bolt failure. I was wondering if anybody could explain how an old bolt is replaced without changing the position of the bolt? Is the same hole used? If not, what will these routes look like in 50 years' time?


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 Post subject:
PostPosted: Mon May 02, 2005 5:52 pm 
Often folks talk about drilling out the bolt, but I would like to see this in practise. SDS bits are for rock & concrete...and should not work to well on steel, unless it is very rusted. Steel bits would be destroyed by the rock walls of the hole.

In most cases the bolt would have to be snapped of by hitting back & forth with a hammer. The remaining portion of bolt pushed further into the hole...if posible. Glue matching the rock colour to conseal the hole. But it will still look a little tacky.


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 Post subject:
PostPosted: Mon May 02, 2005 7:27 pm 
Snapped, why not just use a hacksaw. I've done a little retro-bolting and just use some pratley putty and mix in some lichen or whatever colour is needed. Most times you can hardly see the old hole at all.


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 Post subject:
PostPosted: Tue May 03, 2005 9:09 am 
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Joined: Sat Apr 30, 2005 8:31 am
Posts: 2875
Location: Montagu
Real Name: Justin Lawson
Regarding top anchors that get replaced, why not leave the old bolts in place? Then there will be four bolts at the top of a route (a simple & cheap system could be used to have the old bolts used as an extra backup). After a few more years the old bolts will probably be able to be pulled out by hand and another new bolt can be put in?<br>
Regarding single bolts on the route? Perhaps oneday soon a device will become available that can remove a bolt gracefully? I also wonder what the rock will look like in 50 years time, I've seen a climbing area that has bolts placed for 3rd time and it doesn't look good (cover up glue or not).

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 Post subject:
PostPosted: Tue Jul 26, 2005 10:34 am 
there is a machine for this. ask alard. it's a car-jack type puller.
Your idea about leaving potentially lethal bolts on top of a route is just stupid. the only bolts on a climb should be ones that are actually safe.


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 Post subject:
PostPosted: Tue Jul 26, 2005 5:57 pm 
Pull them out by hand, yes Justin! Not! Maybe in about a thousand years, stainless steel supposedly rusts at 1mm every two hundred years, although I would imagine thats under ideal conditions (hardly the case on a clifftop). Jeremy Colenso used the car jack system, believe me the process was not graceful!!! One in four bolts he removed shattered the rock to some extent. Hacksaws sound good until you realise you cant get flush with the rock and if the bolt is in a hollow then you cant get at the bolt at all, snapping works well on 316 steel (Hilti and new upat) which is soft and brittles up quickly when overstressed but if you try that with 304 steel (old upat) you are in for a hard time, Also in all likelihood you will miss occasionally and strike the rock leaving permanent scars (this I know from experience)

The best method is to use a battery driven angle grinder with a mask or guard (3mm MDF board will do) around the stud to protect the rock. Dont attempt this unless you are very familiar with angle grinders and are extremely competent working on the end of a rope, its just too hazardous. Ask any doctor what the worst industrial accidents are: angle grinders! Also they are noisy as all hell, make sure you have the permission of the landowners to operate the tool on their land first and warn other climbers and walkers that you will be making a noise.

Well thats the theory at least, I still have to make an opportunity to test it out. Derek: still also keen to try drilling them out, have sourced some sds steel bits but unfortunately not Titanium coated, which would be the real deal. Should get a gap to try these theories out in October some time and will let all know what transpired. We need to crack this problem or we are going to leave an aweful legacy for upcoming generations to sort out.

Metolius manufactured a completely removable bolt out of 413 steel (virtually impervious to any corrosion) which was the cats whiskers as then you really could keep reusing the same hole almost forever, but no-one bought them as they cost 7dollars each, and so they stopped manufacturing them.


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 Post subject: Re:
PostPosted: Thu Jul 28, 2005 12:37 pm 
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Joined: Thu Jul 28, 2005 11:59 am
Posts: 132
Location: Pretoria / Johannesburg
Real Name: Andrew Blanche
However impressive it might be, does it not make you happy that we are not able to pull bolts out by hand? Think of that the next time you have clipped and are about to make that dodgy run out move …

As for drilling out bolts by hand…. I have never tried to drill out a stainless steel bolt, but have tried to drill out a mild steel rawl bold from the floor. It requires you to dill 100% down the middle of the bolt with increasing sizes of drills till eventually you have reamed out sufficient steel to either buckle the remainder and pull it out or fish out the bits with a tool. My advise, for what its worth, learn to swear or leave it alone… Oh and you are really stuffed if you break the bit off in the project….

Maybe all this should be a lesson to us as to how important it is to place bolts in the optimal position, using good bolting techniques and the best quality material available so as to give the bolt its longest life span and reduce to need to chop, drill and rebolt every few years.


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 Post subject:
PostPosted: Thu Jul 28, 2005 1:45 pm 
After re-bolting a long magalies route, I found a hammer is the best way to remove old bolts and very little scarring resulted. A hacksaw is a friggin' mission. The old holes we covered with putty and in most cases u can only see them if u know where to look. We were helped cos the original bolts were very well placed (i.e. no over bolting) and they were also real old, so snapped off easily (some just sheared off when we tried to remove the old hangar!) Someone had attempted to pull one of the old bolts near the top of the route with a jack. It made a mess. I guess up in the highveld the best we can do is make sure only stainless is used, so any bolts placed last a long time. Down at the coast its a bit trikier cos of SCC...


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 Post subject:
PostPosted: Thu Jul 28, 2005 8:34 pm 
Probably the answer for our coastal crags. I understood these bolts were out of production (according to Sam Lightner jnr., he would know) but now I see they are featured as a product on the Ushba website. What am I on about? - Titanium bolts. Check them out here: http://www.ushba.com/catalog/rock.html#tortuga
Click on the 'more info' tab and see what SCC can do, frigging scary!!


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