Rock Climbing at Loja

I managed to redpoint the classic 8a at Loja today.

Vibraciones Positiva is a long 35m stamina route that features long reaches on mainly good holds - a couple of the reachs are really long and caused me a few problems - my feet keep cutting loose. See left.

The whole crag is in perfect condition after so much dry weather and its position at 1000m and northerly direction have made it perfect during the recent hot weather.

I have finally taken a week off because Simon came across to visit and it was great to climb together. He has gone back now, but I still have 3 free days before my next clients arrive and so am off to Archidona for more steepness.

It was also good to see Alison B, who came on a course last year and returned to Villanueva del Rosario last week to explore the area some more.

Chris and Ryan arrive on Sunday for a joint climbing course and it looks like the weather is going to hold on being good for them - after that I am fully booked until the 19th December and January is filling up fast.

Chilam Balam Cave - 8b

Very happy today because I managed my second 8b yesterday.

The route is called Golpe de Calor and is one of many fantastic routes in the Chilam Balam cave on the outskirts of Villanueva del Rosario.

The cave and surrounding area have proved very popular as the prolonged hot, dry season has forced climbers to look for shady, high crags. Chilam Balam cave faces north and lies at 1000m There were about 20 climbers at the crag yesterday - not bad for a crag where the routes start at 7c.

Golpe de Calor was equipped and first climbed by Bernabe Fernandez (Amazing roof climber and driving force behind a lot of hard routes in Andalucia) two years ago. Originally graded 8a+/8b it has settled at 8b - the grades are noticeably harder here than El Chorro.

The route is 30 m long with the the first 15 meters on tufas and crimps on a wall that overhangs 20 degrees, then a desperate roof on undercut tufas and slopey footholds with a gripper clip. The top wall is super technical with minimal footholds and a final insecure runout to the chains.

I found it quite hard because I could not get the kneebar rest below the overhang - I wasted a day trying to get my foot and knee to stick before deciding that I was wasting more energy than saving.

On my first redpoint attempt of the day I got past the top crux but broke a small undercut - I really did not think I would have enough energy left for a second go, but somehow managed to fight to the belay.

This was the 5th ascent after Bernabes, Javier Morales, Carlito from Malaga and Urban.

All in all a great route! Thanks to Carlito, Gonzalo and Urban for all the help and encouragement.

The cave has seen a lot of development recently and the climbing topo for the area is fast becoming out of date.

It has been a good season so far - I was worried that after 7 months of instructing clients on a variety of climbing courses with hardly a day off that I might not be route fit, but the evening sessions on my home finger board have paid off and being on the hill has kept me aerobically fit.

La Rubia looks good...

Dry Weather in Andalucia

I'm have been over in Spain for a month now and the weather has been amazing for climbing. I have been completely full on with courses and the warm weather has made it especially enjoyable, but the local farmers have a different view - they are desperate for water.

The photo on the left shows the effect that the dry weather is having on the olives. The olives on top are how they should look at this time of year, but a lot are looking like those at the bottom of the picture - underdeveloped and wrinkled.

Olives are a mainstay of the local economy and this is potentially a big problem. The town ajuntamiento has imposed a water ban between 0100 and 0600 to try and save water, but they really need some rain.

The warm weather means that the high crags of Villanueva del Rosario have been really popular with climbers from Malaga and Granada - the shady crags of La Ventana and Chilam Balam have been receiving a lot of attention and the hard routes have been falling fast despite the fact that the routes are quite harshly graded compared to the routes at El Chorro.

The spanish climbing courses are proving really popular and there I only have 10 free days between now and Christmas.

Worn Carabiners

The carabiner to the left was sent into DMM for testing - I am not quite sure of its history, but the size of the groove that had been worn into the top bar is pretty impressive. DMM see bolt damage to carabiners fairly regularly, but this is exceptional.

The groove had eaten through 27% of the thickness of the bar and the volume of metal that had disappered was even greater.

I fully expected this carabiner to break under 10kN, but it actually acheived 26kN - greater than its rating when new.

It is difficult to explain this especially considering that a much smaller nick in a similar carabiner (see Mamba post below) caused a serious loss in strength. I don't want this post to encourage people to use carabiners in such a bad state, but rather use it as a pointer that there are a lot of variables involved in how and when kit breaks - some obvious and some that obviouslly are not.

DMM customers have asked in the past "how much wear and tear before I should reire equipment" - hopefully the last two posts show that this is a difficult question to answer.

It should be stressed that this carabiner should have been retired a long time before it reached this state.

The second image shows a 30 year old HMS from the days when DMM was called Clog and employed about 10 people. It had a rope groove that had eaten away 6% of the thickness of the bar. It made 24KN.

Old Carabiners + Tapes - Breaking Strengths

Sports climbing carabiners get a hard life.

They are constantly subjected to short hard falls, clipped into sharp or badly aligned bolt hangers and ground against the rock. The tapes also get a hard life as they get grabbed with chalky hands and suffer harsh abrasion, especially as the run over the carabiners.

DMM recently received a couple of old Mamba quickdraws back that were over 10 years old and which the owner wanted tensile testing.

The quickdraws looked in reasonable condition - there was no bad visible fraying or fading on the quickdraw tape, although the ends had some mild fluffing where the tape had been caught between the rock and the carabiner. The carabiners functioned well and with a little lubrication would have been perfect. The metal was free from corrosion, although there were some sharp bolt marks on on of the straight gate carabiners.

The first Mamba we loaded up included the straight gate carabiner with 3 bolt scars on the inside apex. The tensile test started - at about 8kN it was obvious that something was going to pop early because you could hear the tape fibres starting to snap. This does not normally happen to around 18-20kN normally. The real surprise was when the straight gate carabiner suddenly blew out at just 13.6kN - almost half of its rated strength.

On examination it was obvious that the one of the bolt scars had created a stress multiplier that had then opened out the scar to create a full blown fracture.

The second Mamba blew out the tape at 15.5kN - about 60% of its strength when new. Once again it was obvious it was going to break early because the micro damage to the fibres could be heard starting around 10kN.

In a real world situation both of these Mambas would still have done their job - but they would be far less tolerant of stupidity or misuse i.e. connecting a short sling to the Mamba to hold you in position why you work a move and then slipping/jolting back onto it - this creates massive forces that can break new carabiners let alone half strength ones.

The slings blew early because they were old and some minor damage accelerated quickly to cause a complete failure. The carabiner blowing out early was surprising and probably worthy of further experiments because although the bolt scars were noticeable they did not seem excessive.

There is more information on climbing equipment at Rope Rescue Techniques below the main text and informatio on choosing carabiners on the Rock Climbing Outside pages - again below the main text.

Corrosion in Climbing Carabiners - Corrosion in 7000 series Aluminum Alloys

Each year DMM receive back a few carabiners where the surface of the carabiner has corroded and exfoliated. Almost invariably these carabiners have been to Thailand (although DMM have seen similar corrosion from carabiners used in Hawaii). They are often asked for the reasons why this corrosion occurs.

Aluminum alloys are widely used in the manufacture of climbing products because these alloys can offer a high strength-to-weight ratio combined with good ductility and toughness.

There are currently 8 families of aluminum alloys and each family group is identifiable by the first number of its name. The families differentiate themselves from each other by their principal alloying elements:

Major Alloying Element	Series Identifier
None (99%+ Aluminum)	1XXX
Copper	2XXX
Manganese	3XXX
Silicon	4XXX
Magnesium	5XXX
Magnesium + Silicon	6XXX
Zinc (Magnesium + Copper)	7XXX
Lithium	8XXX
Unused	9XXX0

These main alloying elements impart specific properties to the alloy. These properties can be further modified both by the addition of extra alloying elements and processing treatments that occur during the production of the finished alloy product.

The vast majority of carabiners used in recreational climbing are made from 7000 series aluminum alloys with aluminum alloy 7075-T6 being the most widely used. 7075 describes the grade and T6 describes the generic heat treatment process used on the metal.

7000 series alloys have zinc as the primary alloying element together with magnesium. The further addition of copper to the aluminum-zinc-magnesium system together with small, but very important amounts of chromium and manganese gives high strength aluminum alloys that, although initially developed in 1943, are still the benchmark for use in climbing carabiners. There are stronger/tougher alloys on the market, but cost and productivity issues often work against them in a commercial environment.

Chemical Composition Limits (Wt. %)
Si	0.4
Fe	0.5
Cu	1.2-2.0
Mn	0.3
Mg	2.1-2.9
Cr	0.18-0.28
Zn	5.1-6.1
Ti	0.2

Aluminium metal is a very active metal that oxidises very quickly. While this would be a weakness for most metals, this quality is actually the key to its ability to resist corrosion. When oxygen is present in the atmosphere or in the environment (in the air, soil, or water), aluminium reacts very quickly to form aluminium oxide. This aluminium oxide layer is chemically bound to the surface and it seals the core aluminium body from any further reaction.

This is different from oxidation (corrosion) in steel, where the metal oxide (rust) exfoliates, and constantly exposes new metal to corrosion. Aluminium’s natural oxide film is tenacious, hard, and instantly self-renewing. It is this combination of fast oxidation and a protective air-formed oxide film that enables most aluminum alloys to offer good resistance to most corrosive environments.

However the very alloying elements that make the 7000 series perfect for building carabiners make the metal more susceptible to corrosion. It particular it has been established that the addition of copper (2000 series alloys) and zinc/copper/magnesium (7000 series alloys) to the aluminum solid decreases the corrosion resistance of the alloy. This is due in part to the fact that the aluminum oxide film is now not consistent over the surface of the metal and contains oxides of copper, magnesium and zinc which can decrease its protective qualities.

In addition any metal ions passing into solution as a result of corrosion can then be deposited on the surface of the alloy and set up galvanic cells on the aluminum surface. This can dramatically increase the rate of corrosion.

However certain other factors often need to be in place to de-stabilise the oxide layer and accelerate the corrosion process, these include:

• The oxide is not stable in acidic (pH <> 9) environments

• Aggressive ions (chlorides, fluorides) may attack the oxide locally i.e. sea water

• Certain elements (Ga, Tl, In, Sn, Pb) may become incorporated in the oxide and destabilise it

• Contact with dissimilar metals including pressure treated wood (which contains copper) carbon steel and mild steel.

• Heat

• Sea salt (mostly sodium chloride) can help destabilise the normally protective oxide film, leading the localized attack (pitting). This happens because it acts as a facilitator for galvanic metal corrosion.

When the two dissimilar metals come into contact an electrical loop is closed, and the natural voltage differential between them causes electrons to flow. One metal becomes the anode (negative) and one will become the cathode (positive). This electrical circuit causes the anode to lose ions and the cathode to gain ions i.e. the more active metal dissolves. The copper is relatively inactive and the other metals in the 7075 alloy, including the aluminium base metal dissolve/change form. These adverse effects are magnified if the copper is out of solution at grain boundaries.

The most common form of corrosion on carabiners is pitting – small localized corrosion on the surface of the metal. Exfoliation corrosion takes longer to happen and is often more serious – it is a severe form of inter-granular corrosion that occurs along aluminum grain boundaries and causes delamination of the surface of the aluminum with white corrosion products forming between the layers.

Anodising can reduce corrosion in aluminum alloys by increasing the thickness and hardness of the protective oxide layer. The standard anodising process used on carabiners uses chromic acid or sulphuric acid; the anodising process causes a chemical transformation of the aluminum material itself to create a thicker than normal aluminum oxide surface layer. This layer is often dyed and then it is sealed by a secondary chemical treatment, normally immersion in boiling water.

Anodising does help a lot in reducing corrosion, but it is not an alternative to looking after your kit – if the surface of the carabiner is nicked or scratched, such as happens when a carabiner is loaded on a steel bolt hanger, then this will allow corrosion to potentially begin.

In this situation there is a galvanic cell between the steel hanger (even if it is stainless) and the carabiner. The situation is worsened by the large cathodic surface of the hanger concentrating the current flow through the small anodic area of the scratched anodize on the carabiner.

Keep you carabiners dry, cool, away from salts and away from acids. If you do climb by the sea wash your gear in clean, cool water and dry it in a warm environment naturally and lubricate when dry if necessary.

There is more information on a corroded quickdraw set on my web site - see Strength of Old Carabiners

Click on the tab below the main , central text.

Crib Goch

I recently was able to help a client fulfill a long standing desire to climb Snowdon via the Crib Goch ridge.

The weather forecast was fairly horrible with both high winds and rain predicted; the warm-up day was spent at Clogwyn Cyrau near Betws Y Coed rather than Tryfan because of the high winds in the Ogwen Valley. However at least we stayed reasonably dry there and covered all of the rope techniques that we would need on Crib Goch itself.

The following day was looking fairly grim as well, but at least this meant there were parking places in the Pen Y Pass car park.

It was fairly windy on the approach to the ridge itself with lots of low lying clag, but the wind died completely as we hit the ridge itself - perfect timing! The traverse along the famous ridge went very smoothly despite the rock being quite wet and slippery. The Pinnacles at the end of the ridge were climbed successfully before the wind hit us again on the strenuous hike up to the summit.

It was a long day out on the hill and getting late so we opted for the luxury of taking the train back down to Llanberis, where Simon met us for a quick trip back up the Llanberis Pass to the Pen Y Pass.

A perfect example of perseverance and hard work being well rewarded. It would have been all to easy to use the weather as an excuse to not try the ridge, but by taking it one step at a time we stayed safe, in control and were in the right place to make the most of the opportunity when the wind eased. A good day out.