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Ed H
Trad climber
Santa Rosa, CA
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May 28, 2015 - 04:01pm PT
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Ok - thanks Clint!
After the ORG accident, I'm feeling pretty sketch about taking a fall/slider on a 5/16 buttonhead.
Ed
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mucci
Trad climber
The pitch of Bagalaar above you
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May 28, 2015 - 05:58pm PT
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Onyourleft-
That design has the right idea, but I think it would break the majority of hangers or bolt heads
I wonder what the success rate was/is? I would be surprised if it had ever pulled a 5/16ths buttonhead.
It sort of goes against the mechanics of a hanger/compression bolt combo.
Very interesting idea none the less.
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pell
Trad climber
Sunnyvale
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Found this bolt yesterday at Phantom Spires. Is it 5/16" buttonhead?
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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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^^^^^^^^
Looks like a 5/16" buttonhead with a SMC SS hanger. It looks like they had a hard time driving in the buttonhead based on the nicks on the side of the hanger.
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Greg Barnes
climber
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Topic Author's Reply - Jun 2, 2015 - 08:32am PT
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Yep that's 5/16". Just got this photo of another 5/16" buttonhead. This is the first bolt on Blue Velvet at Sugarloaf, apparently the upper bolts are all similar but all spinners (while this one is epoxied down, you can see an old chopped/broken bolt underneath):
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blr
climber
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Add "Only the Young Die Brave" at Sugarloaf to the list. Sugarloaf/PS/Wrights Lake has quite a few of them.
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sowr
Trad climber
CA
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It's possible they may crack as they are driven due to compressive stress, after which ambient temperature related expansion/contraction would add to the stress rise. Cracked areas would be unplated, and corrode more quickly (rock is porous). A perfectly driven bolt (one driven perpendicularly with equal compressive force on both sides) would crack equally on both sides.
I recommend a few things on climbs where these bolts are utilized:
1 - Prior to clipping test the bolt. Off the top of my head not sure how. Direct axial pull: if it comes right out well there's your answer. Gently tap it with something? Will the sound be different? Can flex be detected? Is it obviously excessively corroded? Needless to say easier said than done from a sketchy stance.
2 - Routes with this hardware installed should be rated "X" until re-equipped with suitable equipment.
3 - Guidebooks should present a warning up front, clearly stating the problem.
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Impaler
Social climber
Oakland
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So I went and checked out "Only the Young Die Brave" at Sugarloaf on Saturday. It had four 5/16" buttonhead lead bolts in addition to a newer 1st bolt shared with "The Man Who Fell to Earth". The bolts are from 1989 and look identical to the one from "Jugs Revisited" a few posts up. I tried to remove the 1st of the four to no avail and the best I could do was to bend the hanger enough with a crowbar to get a saw blade under it. Had to cut it, patch it and put in a new bolt next to it. So, my conclusion was that those bolts were REALLY bomber - no need to mess with them any time soon. No signs of corrosion except for a few tiny nicks on the head from the installation. I hung on the other bolts with my body weight as well and they seem to be in the same condition.
As a side question, is there a good way to remove 5/16" bolts? It took me way too long with this one and I broke a crowbar in the process. Is it mandatory to use tuning forks for this and where could I get one (or two?)?
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scooter
climber
fist clamp
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All the bolts on the final direct finish variation of Cryin' Time are 5/16. I never replaced them or thought to because they seemed sufficient. One of them is a spinner now if I remebr correctlly
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BruceHildenbrand
Social climber
Mountain View/Boulder
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^^^^^^^^^^
Since I led the FA of that pitch in 1978 without placing any bolts I'd say take them out and leave them out.
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Stewart
Trad climber
Courtenay, B.C.
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Back in the mid-70s, I was climbing Uncle Ben's with Daryl (Hatten). I was cleaning the pitch when I heard him squawk that the belay was coming out.
Naturally I clipped into everything in sight and hung there terrified while he drilled away and repaired the station.
Not surprisingly, when he finally gave me the OK to come up I asked him what had happened after I reached the belay, noting that we were connected to several obviously manky bolts as well as the new one. His comment was that the bolt that popped was the most solid-looking one of the bunch.
The culprit was a 5/16 Rawl drive buttonhead.
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Juan Maderita
Trad climber
"OBcean" San Diego, CA
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Stewart,
Back in the mid-70s,... The culprit was a 5/16 Rawl drive buttonhead. How certain are you of that?
I never saw any Rawl "Drive" in sizes other than 1/4" and 3/8" in the 1970s. I don't think the 5/16" went into production until the 1980s. The 5/16" went out of production in the 1990s.
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Bruce Morris
Social climber
Belmont, California
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All the bolts on the final direct finish variation of Cryin' Time are 5/16.
This refers to the Dan & Sue McDevitt direct finish on "Crying Time". The finish Bruce Hildebrand did is to the left. There's another direct finish still further left. I'd say the finish furthest to the left is the one that Bill Taylor did. In other words, there are 3 direct finishes to "Crying Time". The Dan & Sue one is equipped with 5/16th buttonheads.
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Impaler
Social climber
Oakland
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Thanks for the link Juan! That's a pretty useful thread as well. Is anyone able to make some of these sort of tools to sell? Or perhaps can anyone in the bay area lend me a one of those big tuning fork/cutoff wrecker bars things/cold chisel with a slot? I'm currently healing up my finger, so no climbing, but I'm looking for replacement projects to make a good use of my time.
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Stewart
Trad climber
Courtenay, B.C.
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Juan: You could easily be right. It was a long time ago.
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Impaler
Social climber
Oakland
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Feb 16, 2016 - 11:58am PT
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"96 degrees in the shade" at chapel wall as well as "Desperado" at Pat and Jacks have scary 5/16 buttonheads with spinning hangers. They seem to be ok shape, but have a bit of corrosion. I just replaced one protecting the crux on 96 degrees...
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SuperTopo on the Web
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vertical = thick stainless
Let us know!