Rusty Bolts 101: be afraid.
October 22 note: There's some possibility that this was an old Leeper hanger; it was far too rusty to see any manufacturing info, but Tony Devonshire recently wrote me to say, "I read the article on your site and just thought I'd offer a suggestion. The hanger looks to be an old Leeper sheetmetal hanger made in the seventies, that hanger has been recalled by Leeper as they are failing (obviously). The design is flawed and several hangers have failed in all ranges of conditions and under very low loads. So, if you have the hanger at home and it's stamped Leeper somewhere you could send it back to Leeper so he can have a look as he is asking for all of the hangers to be sent to him. As far as the self drives go I tried to remove about a dozen at Wasootch last year and well just leave them there and patch over them if you need. The only way to take them out is to break them out."
More info can be found at http://www.safeclimbing.org/Leeper_recall_0402.pdf
Photo by Kim Csizmazia
October 17, '02
At the top of the first pitch of the smears to the right of Marshall Arts I was happy to see a three-bolt belay held together with enough sling to truss an elephant. I clipped into the better parts of it all, brought Kim up and had a good look at the bolts. I was scouting for a TV commercial; it's reasonable in this situation to expect high loads from camera monkeys etc., so I had a really good look at the bolts and decided they were so rusty that I'd quickly test them. I always clip into bolt hangers directly with a biner; the sharp edges can cut slings at surprisingly low loads. It's not good form to tap or beat on bolts, doing so may damage them, so I put the pick of my tool through a biner clipped into a bolt, lined up the load and gave a mild pull. To my surprise the biner cut through the hanger like butter; I wasn't pulling on the tool with more than about 70 pounds of force; the additional leverage of my tool might be at best 4:1, so I think the hanger failed at no more than 300 pounds. Even if everything were perfectly equalized this is far below what a short factor two lead fall might put on the bolts!
More examination of the bolt hanger revealed that where the hanger rested on the rock it had turned into a kind of "rust paste;" I could literally scrap it off the rock with the pick of my tool. Hmmm.... As I was getting paid to to "Scout and Prepare" I fired in two fresh three-and-a half stainless bolts (Bolts paid for by the TV boys) and new thick hangers. I then did my best to remove the old self-drive bolts; I could not get good purchase on them to remove them as only the bolt heads were showing, but they did seem to be quite strong. I'd always assumed the bolt would fail before the hanger, this is not so.
Bolts are increasingly common on mixed climbs that are wet all summer; it's probably a good idea to have a suspicious attitude, and to place bolts out of the summer water whenever possible.