The Dating Game: Beware Expired Bolt Glue
Although this column is ostensibly about diagnosis and management of climbing-related injuries, with a wagging tail of prevention, I had such a close call with an unhealthy outcome that I am obliged to tell my tale of woe.
I’d bolted a route at a less-than-secret crag, a couple of hours west of Sydney on Newnes Plateau, a parkland so vast that when a fire started here last summer it burnt for six weeks before anyone could even get to it.
I hadn’t bolted a route in recent years; too busy building a house, defending said fire when it threatened our house, and then dealing with the COVID maelstrom. But the pull got to me a few weeks back as I repeatedly walked under a couple of obvious lines. I grabbed my gear and a few tubes of glue and bolts and off I went.
Fast forward after the work of cleaning and installing the glue-in bolts, and I was climbing toward the first bolt. Hard the climbing was not, but frightening it was given the chossy start. I got to striking distance of the first bolt and took a draw off my harness with my left hand. In a smooth action—one that we are all familiar with—I clipped the bolt, grabbed the draw, and breathed a sigh of relief.
With an almost inaudible scraping sound, the bolt slid out of its hole!
I didn’t die, didn’t even fall. But for a moment it felt like it wasn’t going to be a fun day. I clawed over to the bolts of a neighboring route and clipped in.
Over the years I have predominantly used glue-in bolts. In the Blue Mountains glue-ins are a must since the soft sandstone doesn’t hold expansions bolts. One person died here some years back after a foreigner placed an expansion on a new route, and it failed when a repeat ascentionist loaded it.
In terms of the bolting process I’d recently used, everything was normal. The glue mixed well as it entered the nozzle. The two parts, visibly different in color turned into the typical grey color.
What happened? The glue, at least in that bolt, didn’t harden, as it was supposed to. The bolts sat and cured for two days before I tried the route, so the glue had plenty of time to set up—it is supposed to harden in a few hours, and fully set in 24.
At home I retrieved the nozzles and glue tubes that I used that day from the trash bin. The glue in all the nozzles had hardened except for one.
I rapped in to the glued-up route a few days later. The top anchor bolts pulled out, as did all the bolts on the route. The bolts looked good, but just a little pressure with a pry bar through the eye caused them to slide out with ease.
In the 1990s, we used a two-part epoxy glue, bought in two separate cans that had to be measured out, mixed manually, and pushed into the hole with a popsicle stick. Today, glue comes in a user-friendly tube that contains the two parts separately. The glue mixes in a special nozzle as it oozes into the bolt hole.
I’ve used various glues, never really paying attention to the chemical make up. Common glues used by climbers are epoxy resin and polyester resin, but there are other types. The glue I recently used was not a two-part epoxy, but rather a two-part polyester—who knew there was a difference? I had thought bolt glues were all the same. And, rather importantly, the hardening catalyst in polyester-resin glue deteriorates in just a few years to the point that it no longer works. My glue, bought in 2016 with an expiration date in mid 2018, was clearly expired.
I talked with a tech guy from one glue manufacturer and he pointed out that the expiration date is critically important—if you think taking a big glig of expired milk ruins your day, the consequences of using expired glue can ruin your life.
Chris Vinson from Climbtech, maker of various bolts including the glue-in Wave Bolt, says polyester glues have a shorter shelf life than other types, but that any expired glue is dangerous and must be thrown away. Whatever the glue, he says, “Best practice is to go with what the manufacturer recommends and not to deviate based on personal experience.”
I threw away half a dozen tubes of expired glue. At $50 a pop it hurt a little, but I figure I will forget the expense sooner than I would have forgotten the consequence of falling onto a bolt set in expired glue.
This article appeared in Rock and Ice issue 266 (November 2020).