Last night I attended a Bolting Workshop at Bus Stop Quarry, delivered by Chris Parkin. As part of remaining current and striving to improve our knowledge technically and professionally, us members of the Association of Mountaineering Instructors (AMI), register a certain number of days CPD (continual professional development) per year. Last nights workshop will count towards 0.5 of a point towards those CPD required.
Chris demonstrating the placement of a stainless steel expansion bolt and hanger
Firstly we talked through the professional ethics and law to do with having a good understanding of bolts and their quality… If a bad one were to fail and an instructor’s client injured, there may be a case for negligence.
Then Chris drilled and put in a 10mm stainless steel expansion bolt, nut and petzl hanger. Rated to about 25kn, we tested it to 10kn (1 tonne), and it held totally fine. Should a bolt like this receive excessive use over 5 years in a softish rock like the Slate Quarries, then it may start to wobble and move around. Recent testing by Mark Reeves showed bolts in this category still hold to about 1kn outward pull. Which isn’t in my opinion overly dangerous as was reported by BMC etc, but I certainly wouldn’t be top roping groups of clients on those bolts.
He then placed an alternative which is a 6mm rod hanger, held in by resin. It was a hot day, and after less than 1 hour, the bolt tested to 5kn of outward force (6-7 climbers all hanging directly outwards from it, and it would hold) These bolts are believed to be slightly more suited to the slate, as long as they are not constantly being loaded sideways to create twisting. The correct placement by the person doing the drilling and glueing is therefore extremely important.
Old bolt circled, New bolt with arrow.
I then asked Chris’ opinion of the single bolt belay that exists above Solstice and Equinox (used last weekend). It is an 8mm bolt with hanger, the bolt sits inside a barrel in the rock… Both the bolt and barrel looked to be heavily corroded. There is a sling placement around a big bolder to the right that forms the main part of my belay, but it would be tragic for the bolt to not be backed up by a climber and failure to happen.
So, Liam and Konrad were properly keen to get the drill going and resin in a new bolt for practise and to work the new skills we’d just seen.
There is now a new 6mm resin bolt directed towards the climb which should be good for 20 years at least, and would probably hold 30kn directionally (2 ford fiestas). Considering the traffic these routes get, I think this new bolt is a good thing. Shame about some of the old bolts which are there, I think the hangers were taken from them for no good reason (that I know of).
Think I’ll go and have a look at the ‘Gnat Attack’ belay next. Safe Climbing people. T
TerryJamesWalker 