Wednesday, May 30, 2018

Galvanic Frustration

I hate to think that Newfoundland is the only place placing bolts on sea cliffs in Canada, but apparently so. If you had noticed, most of the routes in NL are bolted with stainless steel (SS) glue-in bolts. This is awesome as they are very low risk to corrosion, the bond between the rock and bolt is stronger than the rock itself and finally there are no voids or compression points that could result in bolt failure. But they are kind of a pain in the ass to lower off.

I have been to areas where they have fixed draws at the top of sport routes and it makes life so much easier (and safer). The future routes I am going to put up, I intend on placing fixed draws. My challenge is Galvanic Corrosion! It is accelerated corrosion that occurs when there are 2 different metals touching in a wet salty environment (Newfoundland). It is basically the same principle batteries use. Two different metals with a difference in electrical potential (high school chemistry) can generate a current and break down the anode (more negative) of the battery. The two metals must be connected by an electrolyte solution ie-salt water. So, if I use a SS bolt and place a zinc plated chain for the draw, it doesn't last long (pic). I believe there are one or two routes on Main Face that are badly rusted out because of this.

Mountain Equipment Coop is my 'go to' place to get my fixed gear. I have always used either SS 3/8 compression bolts (inland) or SS 12mm glue-ins bolts but I have either placed rap anchors or just the glue-ins. I used to get SS carabiners thru MEC but they don't carry them anymore. What they do carry is a SS Cold Shut that fits a 3/8's bolt. This can't be used with a glue-in (preferred on the ocean). I could use a SS 3/8 compression bolt but less than ideal. I tried to order 10 tonight but it will take 6-8 weeks for delivery.

I had planned on using Fixe Gym Carabiners to retro fit routes that I had used glue-ins. The problem is that they are a zinc plated steel and the will suffer galvanic corrosion. Let me stress that they will be safe but they will only last 3-5 (or longer) years instead of 10-20 years. I am going to use a SS quick link between the bolts and the draw to assure that no damage occurs to the bolts. Once the carabiner are suspect, the carabiner can be switched out. That is a lot easier than re-bolting.

Of note, Fixe does have SS carabiners but they are 31 USD each plus duty (50ish CAD). A bit too steep. There are other types of SS carabiners but they are for marine use and not rated for climbing. There are also other fixed draws available but they are zinc plated steel as well.

Just remember, you are responsible for your own safety and if you feel something is suspect, don't use it or back it up.

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