Observations without much in the way of analysis
Occasionally we see evidence for the diffusional path of hydrogen. Many thanks to Luis Fernandes Silva for the photos and sample. I was skimming through some photos that Luis sent me a few years ago when one in particular, from Sesimbra del Drento, caught my eye. This crag is a high-sulphate, sea cliff where the […]
The sulphate cliffs of Cabo da Roca demolish stainless steel. This fixed hanger is an exception. Many thanks to Luis Fernandes Silva for the sample. To date, the main thrust of this blog has been to attribute the extreme corrosivity of sulphate crags to the action of sulphate reducing bacteria (SRB). It has been observed […]
Since the last post, events have overtaken your host that mean the already slow rate of posting is going to be even slower. Some three months ago I demonstrated my long held thesis that old climbers simply don’t see height as a hazard, and I took a long fall off an easy un-roped section I […]
A tale of poor materials quality control. I needed a couple of samples of 304 for the development work I was doing, so I cut them from the threaded end of the bolt illustrated below. It’s nothing special, just a random sample from my large collection of old, glue-in, machine bolts extracted from crags around […]
It’s not just the material you use, but critically, it matters how you use it. I have been researching the possibility that the brittle fractures we are seeing at Cabo da Roca and Sesimbra in Portugal are hydrogen embrittlement (HE) fractures mediated via the presence of sulphate reducing bacteria (SRB). Austenitic stainless steels like 304 […]
The benign cliffs of Campo Escola da Barra da Lagoa I reported wall-wash results from this low-corrosion crag some time ago. The sulphate levels were not elevated, a fact which supports my mantra “no sulphate – no corrosion”. However, it always interesting to take a somewhat deeper look, which I was able to do thanks […]
This note was posted to the Titanium Bolting FB Group 1st April 2020 Being locked down is not so bad if you can keep working in your lab. I’ve finally caught up with some wall-wash samples sent to me by Rodrigo Castelan Carlson from the beautiful granite slab sea cliffs of Campo Escola da Barra […]
This note was posted to the Titanium Bolting FB Group 10th March 2020 Warning: This gets a bit geekey, but I’ll simplify as much as possible. For the past few years I have concentrated on providing sufficient evidence for the theory that all marine crags showing SCC of 304SS are associated with high sulphate levels. […]
This note was posted to the Titanium Bolting FB Group 7 March 2020 Everyone knows and loves those huge lower-off rings we find at the top of climbs at Railay/Tonsai.However, some of us began to love them a whole lot less when it became clear that they too were subject to the dreaded SCC. If […]
This note was posted to the Titanium Bolting FB Group 29 January 2020 The hero of this piece is Martin Roberts who burnt countless hours of quality time, when he could have been climbing, installing a large range of anchor types in a whole pile of locations across Railay/Tonsai. My motto is to “measure more and […]