Caving Wrench

[chh]

Some types of bolts are not meant to be tightened very much beyond finger-tight, whereas other types depend on tightening to initiate expansion.

This is true. I just spent a little time helping to check some bolts at one of my favorite climbing crags. We had a torque wrench, which was really nice, but far to heavy and large to cary caving. Our torque wrench was set to 40 if I remember right, and these were Fixe 3/8th inch expansion bolts if memory serves. I found it very helpful to know about how tight this was, as I knew before hand that you CAN tighten an expansion bolt too much, but I just didn't know how much that was. I'd recomend getting a torque wrench and playing around with it so you get to know how tight is "too tight".

On the other hand, if it's a glue in and all the nut is doing is holding the hanger in place, I usually just check to make sure the rope isn't running over it, and that it won't come off. Usually there is enough thread exposed that even if the rap was enough to loosen the nut, it wouldn't come off unless you were doing some crazy pendulum swings or something repeatedly.

Lock-tite is a good idea......but I don't normally carry it.

It's FRIDAY

[Tubo Longo]

Anyway, I was thinking it would be good to stick a small wrench in the pack on vertical trips. I was thinking something like a cone wrench (see pics). But I'm not sure what size to get. What are the most common sizes for bolts?

In Europe the most popular self drives were 13mm. Not sure about here.

Roger

Roger is right: nuts size in metric is #8, so you need a #13 wrench. BUT... some glue-in hanger have (had?) #10 nut, i.e. the need for a #17 wrench. Which, btw, is the same size of the maillon rapide, so very useful if the lock of the maillon get sort of stucked after either a long vertical trip or a wet trip. FIAT (yes, the automaker) was used to give (as part of the emergency set) a double wrench, #13 and #17: very nice.... In Europe I have seen most of the cavers carrying a double wrench, one side closed and the other open.

The idea of the adjustable one is great, but I never found one which survived other than a few vertical, alpine caves trip, so I gave up.

Cheers -- Renato