Torque tips

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BAbycoat
Posts: 163
Joined: Thu Mar 08, 2007 12:53 pm

Torque tips

Postby BAbycoat » Mon May 09, 2011 3:38 pm

My travels take me to Bukit Keteri in Malaysia this coming week - and I read an online review that it has "numbers of loose bolts". Optimistically assuming that only the nuts are loose (and not wanting to start a discussion on David Lama's bolting ethics), we'll take a few 17mm ring spanners.

Given the potential for SCC, I don't want to over-tighten the bolts. We won't have a torque wrench. Can anyone suggest rules-of-thumb as to how tight is tight enough?

thanks.

pierre.joubert
Posts: 724
Joined: Tue Apr 24, 2007 1:59 pm

Re: Torque tips

Postby pierre.joubert » Mon May 09, 2011 4:57 pm

Take a shifting spanner, I've encountered weird sizes (12mm bolts/imperial sizes) when tightening nuts.

As for a general rule of thumb, if it is an expansion bolt that has been properly set, it only requires the nut to be tight enough to stop the hanger from spinning. Experience could replace a torque wrench :bom:

Oh and as for SCC, the actual type of bolt and material would be the main factor in determining whether the bolts would be subject to SCC: Rolled vs turned bolts (all the bolts that have failed in SA were the turned ones, stainless 304 - problem is it's not easy to tell which are which after they have been placed, unless you are familiar with the specific bolt brand/model in question)

Other factors include: How far are these bolts from the sea? Prevailing winds? Relative humidity? Is the limestone the same type of aggressively corrosive one found in southern Thailand (from the location it looks like it).

The ARF has interesting info about this. http://www.climb.co.za/anchor-replacement-fund/.

And if they are loose glue-ins, well then :( watch out for dodgy fixed ropes as well, a girl in Ton Sai fell an entire pitch after sitting back in her harness clipped only to a fixed rope used to access an upper tier crag. She was nicely caught by jungle and survived.

DavidWade
Posts: 164
Joined: Wed Feb 02, 2011 11:13 am
Real Name: David Wade
Location: Benoni

Re: Torque tips

Postby DavidWade » Wed May 11, 2011 8:57 am

Is there a reason why no one uses nylock nuts when bolting routes? Because nylock nuts wont work themselves loose.

deSouzaFrank
Posts: 88
Joined: Thu Jul 14, 2011 8:26 pm
Real Name: Frank de Souza
Location: Middelburg
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Re: Torque tips

Postby deSouzaFrank » Fri Apr 25, 2014 1:23 pm

There is no reason why you can't use nylocks (I would say) As long as they are made of the same stainless steel grade. Ive always thought, that if I ever got to bolt something I would use locktight, burr the thread of nut and bolt once its tightened or even hacksaw down the centre of the bolt head and wedge the two halfs slighly open. Locktight just seems to be the least effort and fail safe.

Old Smelly
Posts: 318
Joined: Fri Nov 28, 2008 1:21 pm

Re: Torque tips

Postby Old Smelly » Fri Apr 25, 2014 1:52 pm

Loctite is great! In some circumstances however you should remember that lock tite removal in the industry is done by heating the bolt/ nut & then the loctite loosens - so in some cases cyclic heating will have the same effect.

Nyloc nuts on the other hand give you the opportunity to tighten to just the right torque & KNOW that the nut will not work loose. Its a bit of a no brainer apart from the cost. The same material is a great idea as there is no chance of galvanic corrosion - which could take place if you used a plated bolt and a stainless hanger or vice versa, but should be ok with different grades of stainless. Galvanic corrosion will take place in a seaside environment if the materials are dissimilar. Though this may seem like a wild herring chase it is just as likely as Stress corrosion if you use different materials.

Great Article here...http://www.climbing.com/climber/built-to-last/
Really, its not that bad...I think it's my shoes...


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