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Larry
Trad climber
Bisbee
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Jun 26, 2010 - 02:06pm PT
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Weld_it should apprentice to you, JM.
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Jun 27, 2010 - 09:09pm PT
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Cragnshag-
There are some new load cells in the garage. The one in the photos is meant for testing bolts. My readouts will work fine on 12 volts.
My old structural engineering prof always told me that fine threads don't provide any more tension than coarse for the same torque. Coarse threads might be better since they don't damage as easily.
For good, clean, steel threads he always said that test data indicated the correct torque was:
Torq = (0.2) x (tension) x (bolt diameter)
T=0.2FD
Hydraulics might be the way to go, my little ram in your photo combined with a smaller pump.
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cragnshag
Social climber
san joser
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Jun 28, 2010 - 01:50am PT
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Nice avatar Banquo. I could use a maple bar right about now!
Yes, let's make a portable version of your hydraulic puller. I can bring a couple sections of HSS from the yard for starters. I would be curious to see the strength of old 3/8" stud bolts, pulled in direct tension (assuming the threaded ends are still usable). Gotta make sure the ram isn't too hard to push since we'll be hanging off the side of a cliff...
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Roger Brown
climber
Oceano, California
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May 24, 2011 - 10:11pm PT
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Juan,
I made 4 tuning forks using your ideas. 2 from the Bosch tile chisels. I like those the best:-)
Thanks,
Roger
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mucci
Trad climber
The pitch of Bagalaar above you
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May 24, 2011 - 10:29pm PT
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TORK pulls 5/16ths consistanly with a standard (bent tuning fork).
I ALWAYS drill out the hole to 3/8ths provided it is a 1/4", Although I hand drill everything.
Cheif, you are using a powerdrill correct?
There is absolutely no reason not to drill out any hole that has had the bolt removed. Just put in a 1/2". Comments on rock integrity are not warrented when you are using a machine.
If your not using the same bolt location your just adding to the problem MOST rebolters are attempting to eradicate....
MORE HOLES.
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cultureshock
Trad climber
Mountain View
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Dec 17, 2013 - 01:26pm PT
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Bump for a cool thread!
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Roger Brown
climber
Oceano, California
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Dec 17, 2013 - 03:19pm PT
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Most of the ones I have pulled over the last couple seasons have been short. Like inch and a quarter. A couple every season just pop right out. Reaming out the hole with a power drill is pretty much a crap shoot and may be the issue. Bad hole=bad bolt. Good hole=good bolt. Most 5/16 I have pulled have been bomber, but you just don't know till you try pulling them. I made a hand reaming tool last off-season that reames the hole without any further drilling. Binding and chipping that 3/8 bit is now a thing of the past, mostly:-) I think the problem of spalling out the hole may be a thing of the past also. Been working on new toys for next season that just may do the trick. But..... most of the stuff I made last off-season turned out to be worthless.
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Greg Barnes
climber
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Dec 17, 2013 - 10:49pm PT
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Cool Roger, if you get a system dialed, let's head to E Cottage (Disintegration/The Bulge, Orange Plasma, maybe one other) and get those 5/16" replaced. Several loose hangers, although I think it's rock breaking out from under the (good stainless) SMCs. Those 5/16" buttonheads have probably had more falls than every other 5/16" in Tuolumne combined.
Royal Flush on Medlicott too. Rusty buttonheads, Leeper hangers, water streak. Fair number of 1/4" nearby as well.
Tons down at Courtright and elsewhere which mostly seem totally bomber (for now)...
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bhilden
Trad climber
Mountain View, CA/Boulder, CO
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Bump for all the hard work and good ideas!
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Clint Cummins
Trad climber
SF Bay area, CA
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Roger has an improved reamer and used it this summer when replacing many 5/16" on Elephant Rock right of Sky. He said it works very well.
(The reamer widens the 5/16" x 1.5" hole to 3/8" diameter, then you
can drill it deeper without the big problem with the bit binding in a 5/16" hole).
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