Stop! What are you about to clip? Dave Musgrove rubs away the rust to find out more.

Fixed protection in the form of wedges, threads, pegs and bolts have played an ever-increasing part in British climbing for more than 50 years. And the latter two, being manufactured from a variety of metals, have been rusting away on our crags for decades. Some seem to have stood the test of time better than others, still looking good after many years. Others have rusted away completely - the only evidence left being a brown stain leeching from a corroded stump. And there are many lying in between these two extremes. The question is - what can you trust?

It’s tricky. Both the early home made metalwear and the later commercially available items were, and still are, made from a wide variety of metals. Additionally, corrosion is a complex chemical process which may act very differently on the same metal in different situations or rock types. The environment may have an influence, and a peg or bolt that may last twenty years with little sign of decay on a dry section of an inland crag can corrode to dust within three years on a sea cliff, or even a crag within a few miles of salty sea air.
It is probably fair to say that most climbers with a few years of outdoor experience treat all pegs with a healthy degree of suspicion. They know that an un-corroded peg head and eye is no evidence of security. And even the most experienced climber won’t always be able to judge the length of the shaft or the quality of the placement. And what’s the effect of corrosion on the stem, buried in the dank depths of a crack? It’s impossible to tell - most agree you’d be crazy to blindly trust a peg.

However the relatively recent boom in pure sport climbing seems to have given rise to a false sense of security. Relying on mechanical bolts of various types or anchors held in place by resin glues and cements, these fixings are more trustingly relied on for various reasons. As protection points they are often quite close together and usually placed in apparently sound, compact rock. And there are normally two fixed points placed close together at the top to form the belay. Everything all looks safe enough, it’s just like the climbing wall. Or is it?

Whilst there have been several accidents due to pegs breaking or pulling out, there have been very few accidents in Britain due to failure of bolts – so far. But as the bolts get older, just what do we know about the corrosive forces at work inside, the microscopic hair-line cracks developing, or the degenerative processes at work within the chemistry of the resins? The answer is very little.

We trust to fortune. If it looks OK we risk it, and of course we all accept risk as a part of our sport. As with all protection, we can never be 100% certain of the quality of the rock in which we place our bolts and over time, and just as our cliffs and crags decay and crumble, so will our bolts. But what we can do is seek to minimise, manage, and highlight some of those risks for the benefits of the placers of bolts and more importantly you - the climbers and users.

To this end, the BMC has recently brought together scientific expertise from chemists, mechanical engineers, metallurgists and geologists, along with many years of practical experience from climbers who have placed bolts and, perhaps more importantly, examined old bolts during the process of replacement. Their aim is to examine current practice and advise on methods and materials to ensure that safe minimum standards are clearly understood and available to activists involved in placing new, and replacing old, bolts on British cliffs. A document will eventually be produced which it is hoped will be useful to influence the thinking and decision making process of those about to embark on sport climbs, about to commit to an irreversible move above a rusting fixed relic of doubtful origin, and those who may contemplate placing bolts or pegs in the future.

Dave Musgrove is a long-standing Yorkshire activist and member of the new BMC Bolts Working Group.

TRUST Vs. RUST
Preliminary findings and areas of interest of the new BMC Bolts Working Group:

Resin
Reassuringly there’s no hard and fast evidence of seriously dangerous practice as yet but there are some suggestions that Polyester based resins may not be suitable for long term use in alkaline rocks such as limestone. Particularly in wet porous rock an adverse chemical reaction may occur causing the resin to degrade faster than non-polyester chemical cements. And once in place it’s hard to the untrained eye to spot the difference.

Stainless
Several types of industrial mechanical bolt (through bolts and Rawl-type expansion bolts) have been adapted by climbers, and simple 10mm diameter through bolts are now the most common and easily placed fixing throughout the climbing world. However those made of cheap mild steels, even with galvanised coatings, will rust and corrode much more quickly than stainless steel versions. Stainless steel may be twice as expensive but can last ten times longer. And in sea-cliff environments the rusting process is enhanced considerably in non-stainless products.

Mixed Metals
Mixing metals has recently been realised to shorten the effective life of bolts. A mild steel bolt with a stainless steel hanger will actually corrode quicker than an all-mild steel unit. Even a simple mild steel washer on an otherwise all stainless unit is potentially likely to speed up the corrosive process. The evidence is fairly clear that stainless steel bolts are probably one of the safest long-term options but only if placed correctly in good solid rock and fitted with stainless steel nuts, washers and hangers.

Rock
Limestone, in particular, is a fickle and very variable medium in which to place bolts. It’s pre-historic marine origin combined with the stress and strains of millennia of geological upheaval and weathering give rise to a wide range of structural quality with fracture lines from very obvious breaks and flakes to microscopic hair line cracks which are difficult to detect. Placing bolts in such a variable medium is not an exact science and activists can only learn by experience what constitutes a good placement. Once placed subsequent climbers putting their faith in such bolts should also use their own judgement. Cracks can widen over time, roots of plants can exert huge internal forces and even quite large blocks can become dislodged. The scree slopes below many cliffs should provide ample evidence that nothing lasts forever in any cliff face environment.

Environment
In addition to the mechanics of bolt types and placement the group will also look at some of the environmental considerations, shiny stainless steel may be the safest from a climbers point of view but offensive to lovers of nature in sensitive locations. Advice will be given on camouflage to lessen the visual impact.

It’s not our intention to deter anyone from sport climbing in the short-term future! Accidents due to bolt failure or bad placement are very rare and the rewards of a successful redpoint of some soaring, overhanging line of compact white limestone can be immense. But the research by our Bolts Working Group will enable us to give advice on making that experience even safer for all concerned.

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