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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 27, 2010 - 11:01pm PT
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Ok Steve, we should go see which rivets pull without damaging the rock.
You create USELESS holes with machine heads.
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Thorgon
Big Wall climber
Sedro Woolley, WA
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Oct 27, 2010 - 11:16pm PT
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Excellent, another thread about bolts and ideas for bolt ladders! The split shaft are bomber and for a bolt ladder they have applications, but the 1/4" SS wedges are way strong based on that one test! Those SS 1/4" wedge anchors would be nice while on some 5.10+ runout freakshow friction slab hand drilling, calves cramping while your toes turn blue!!! I always liked the Red Head 3/8" self drilling bolts BITD for friction routes, then you do not need a drill....But I always brought extra in case I broke a tooth, then top it off with a SS cap bolt and SS hanger and your golden!
The problem with the self drill is the size of the hole once the bolt needs to be replaced. It is possible to drill out the center wedge with a high speed 3/8" drill then the Red Head can easily be pryed out. But then you would need to place another Red Head self drill or fill the hole with glue/granite?
just typing out load,
Thor
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Oct 27, 2010 - 11:22pm PT
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I remain amazed at the apparent strength of the 1/4" expansion bolt. It just doesn't seem possible. Look at the bloody thing closely sometime and you will see how skinny it really is in a few places, because of the threads cutting into the shaft and the cone thingy and so on.
Accordingly the Rawl 1/4" buttonheads should be hugely stronger. Or am I getting excited about a single test that might not hold up when replicated? I think you need to bust a few more bolts, mate!
Greg, explain to Steve why machine bolts are no longer cool.
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 27, 2010 - 11:27pm PT
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Steve already knows.
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Steve Grossman
Trad climber
Seattle, WA
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Oct 28, 2010 - 12:21am PT
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Do what you like...the cabled hangers should break before a properly placed machinehead fails. Shallow anchors aren't really intended to hold long falls so the last hole in the ladder should be a larger bolt and hanger to keep the installation intact. I usually place a smaller diameter stud with a keyhole hanger every fourth or fifth hole in a ladder to keep the tear out potential low.
If a machinehead actually pulls out then upgrade to a slightly larger machine bolt to replace it...but then what do I know???
Pete- Greg isn't your mouthpiece so provide the explanation yourself if you think that my methods are "uncool," as you put it.
How much ladder drilling have you estimable gents actually done?
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 28, 2010 - 12:50am PT
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Steve,
All this talk about falling on rivets and breaking hangers is absurd.
No way you are gonna fall whilst drilling a rivet ladder.
So you are thinking about the future teams again?
Early ascent teams should think it prudent to bring a drill kit.
Edit: Hey steve, how do you reuse a hole when there is a stud with no head?
If you try and remove a machine head, the rock comes with it.
You should know this.
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Steve Grossman
Trad climber
Seattle, WA
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Oct 28, 2010 - 12:55am PT
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I am not worried about falling while I am drilling a ladder. With rivet hanger failures being fairly common for a wide variety of reasons, sustainability for subsequent parties is the issue.
Why not do the best job that you can on the FA?
I have been placing 3/8" bolts even on desperate stances for decades with the next climber in mind. Too freakin' bad that 3/8" split shaft Rawlbolts are garbage because I have placed a lot of them in vain.
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 28, 2010 - 12:59am PT
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Oh, and on the few ladders I have been a part of, we used 1/4 in bolts with hangers every so often, just like you.
For the middle, the z's go by pretty quick.
I am not concerned about future parties, just my own ass at that particular moment in time.
Edit: Yes you have drilled big bolts, and you have unrepeated routes.
Fact is, there is a good 20+ years that need to go by before most modern NEW routes get a repeat. By then ALL of the metal is suspect.
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Steve Grossman
Trad climber
Seattle, WA
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Oct 28, 2010 - 01:01am PT
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Your last sentence says it all...
If any anchor shears off then your options are clearly limited.
Stainless steel machineheads should have a very reasonable service life exceeding 20 years easily. I would have never placed any mild steel bolts or machineheads BITD had I known what I know now.
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 28, 2010 - 01:06am PT
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Steve....
I drill 3/8 SS at the belays if needed.
there you go again with the doomsday critique.
We are talking about rivet ladders here.
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Steve Grossman
Trad climber
Seattle, WA
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Oct 28, 2010 - 01:08am PT
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"Doomsday critique?!?" Please...
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Greg Barnes
climber
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Oct 28, 2010 - 01:11am PT
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The manufacturer data says that stainless 1/4" studs would generally snap in shear around 1500 lbs, not 2500. That's the performance data on the Powers stainless studs, I could see the Hiltis being better but not that much better. The powers ones are stronger in tension so the testing methodology may make a difference, and of course the sample size here is one.
We got a box by accident one time and they didn't want to bother shipping them back, so I gave them away to a friend. Actually used a couple to bolt down a drainpipe.
Buttonheads are stronger in shear (around 2000 lbs), and removable - the studs will snap if you try to remove them.
As far as the machine head debate, I know basically nothing besides 2nd and 3rd hand opinions. The only ones I've replaced have been at free climbing anchors, and they popped super easy. Some cratering but it didn't matter since I was drilling them out to 3/8" anyway.
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 28, 2010 - 01:12am PT
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If any anchor shears off then your options are clearly limited
Sounds grim.
Now if you had read my post you would have noted that not EVERY placement is a rivet...
The last tends to be a bolt. Just like you steve, you know to prevent that huge fall off of the rivet ladder.
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Steve Grossman
Trad climber
Seattle, WA
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Oct 28, 2010 - 01:17am PT
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I did read your post and made no such assumption.
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Banquo
Trad climber
Morgan Hill, CA (Mo' Hill)
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Topic Author's Reply - Oct 28, 2010 - 01:17am PT
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One test isn't worth much but it does give an indication. I usually say that I need at least five to make a reasonable probability statement *IF* the data isn't too scattered. This would take a lot of time to achieve with so many variables.
The test wasn't shear or tension but some combination approximating a hanger loaded parallel to the face and down, (I actually loaded up) the proportion of shear and tension could be figured out from the 4th photo by applying a little statics (did I tell you I'm teaching statics this semester?).
The red ram is hollow and the threaded rod runs from the green load cell through the ram to a nut.
One variable none here has mentioned is the rock. The piece I have is pretty hard. Hard to quantify how hard.
So it sounds like people want about 6 types of 1/4" anchors tested. We need 5 in shear, 5 in tension and maybe 5 kinds of rock. If the data scatterers, we better do twice that. so:
6x(5+5)x5x2=600 tests (check my math for me, I'm sleepy)
Then we need to add some corrosion variables including limestone, salt, the various metal combinations.
I think I need funding.
As far as the zinc POS goes, I think a full size climber (Mucci what do you weigh, 180 or more? We met once and I forgot to weigh you) could pop one with a 1 or 2 foot drop in stirrups. Might be able to break one with a couple solid bounces - but probably better than bat hooking.
Cripes, I type too slow to keep up with you guys. I'm going to bed.
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 28, 2010 - 01:22am PT
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I guess we are on the same page then Steve.
both of us are worried about rivets so we place bolts every so often.
The longevity of any placement is not likely calculated.
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Steve Grossman
Trad climber
Seattle, WA
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Oct 28, 2010 - 01:24am PT
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I would love to actually know what those 5/16" X 3/4" stainless machineheads hold when loaded in shear. The Grade 5 machine bolts that I used to use are a bit stiffer than the readily available stainless bolts.
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mikeyschaefer
climber
Yosemite
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Oct 28, 2010 - 01:34am PT
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Fact is, there is a good 20+ years that need to go by before most modern NEW routes get a repeat. By then ALL of the metal is suspect.
Not to mention, getting a repeat of a route in the valley or elswhere is damn near impossible (outside of your friends). No traffic to worry about.
Not sure about your facts. All of the routes I've established (except one where no bolts were placed) in the last 5 years have seen repeats (or attempted repeats) in Yosemite. Even by people I don't know.
I've been placing 1/4" split shaft on lead and then pulling and filling with SS 3/8". But I do care what the second ascent teams experience is. I take a fair bit of pride in establishing a route that can and should be repeated.
If I had left the holes as 1/4" I bet the routes wouldn't of been repeated. That would suck.
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mucci
Trad climber
The pitch of Bagalaar above you
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Oct 28, 2010 - 01:34am PT
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Might be able to break one with a couple solid bounces
First one I placed, I jumped up and down so hard I hurt myself.
I have also hauled and jugged on a series of 10 year old 3/4in Zmacs with a machine head and buttonhead thrown in for good measure.
No Danger.
Edit: Mikey-If I had left the holes as 1/4" I bet the routes wouldn't of been repeated. That would suck
Jesus are you serious???? Kinda picky teams wouldn't you say?
I want the SA team to get a good route, and by placing zmac rivets on a line does not transform the route into a death show.
Reclimbing a big wall and replacing all the hardware to 3/8 is something I would never do. All the more power to you.
Edit: Mikey I was refering to Wall routes, now that I read your post, I believe you were talking about free routes? In which case I agree 100% in replacing 1/4" hardware placed on the FA with 3/8ths.
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bhilden
Trad climber
Mountain View, CA
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Oct 28, 2010 - 02:46am PT
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Thorgon,
I am not too keen on any of those self drives for the simple reason is that you drill a 3/8" hole then screw in a threaded 1/4 bolt to attach the hanger. That seems like a lose-lose situation in that you have to drill a 3/8" hole, but you end up with a 1/4" bolt. More time for less strength doesn't seem like a good trade-off to me.
Bruce
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