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overlord
Aug 5, 2007, 10:54 AM
Post #51 of 70
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Registered: Mar 25, 2002
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edmontonalta wrote: overlord wrote: edmontonalta wrote: SkaFreak wrote: Like I said earlier, it is a troll. He contradicts himself, he suggests everything absurd that he can, he doesn't really give details. This is the picture perfect example of a good troll. It's absurd enough, but yet he did a good enough job of it to make you all bite. This combined with his other posts made it obvious that he was simply trolling. If he made it any more obvious, he would be making a post saying "I am a troll you twits". edited to add: Mods, you should probably just delete this thread, or at least move it out of the beginners forum. so, i went out and bought bolts, slings, drill bits, reverso, spent an hour drillin a hole in rock, etc just to do a troll???? grow the fuck up. you are either... a) a troll or b) so blatantly ignorant that i wish you were a troll. you asked for advice. despite the question asked wasnt really on the smart side, some folks answered according to their best knowledge. you might not have liked the answer, but thats the way it is. they gave you advice their experience told them was good (get instruction, dont bolt...), not advice you wanted to hear (just got ahead and bolt the thing). well, tough. you DO NOT have enough experience for bolting and the tools you choose proove this point further. and you keep ignoring good advice that people who have more experience (and that experience has originated from mistakes ppl made, believe me) give you. climbing is not a venture where you can be stubborn and stupid. please, choose something else to do. if you do not want to learn and even deny your own ignorance you will only get hurt. in climbing, you are always learning and the sooner you believe there is nothing else to learn, the sooner you end up in a hospital (if you are lucky that is, if you are not...). You guys just insulted me and gave me zero advice. you guys are totally rude and unhelpful.
what?? didnt you read the replys you got? well, if you didnt, that would explain some things, like you insisting on not listening to good advice you asked for.
here are some posts that are not insulting and offer good advice. and that was found in less than 30sec on the first page of the thread:
sky7high wrote: No offense, but please don't bolt. Please don't learn over the internet. How long have you been climbing? People I know that have more than 10 years climbing hard are still not experienced enough to place bolts. Judging by your only other post you're nowhere near experienced enough. I insist, DON'T BOLT. You can get someone killed. flint wrote: I would follow the advice of the first person. If you are not satisfied with that, take a class. If you are to poor for classes and books, then you are to poor to afford bolts and the numerous bits you are going to go through. Best advice, set up a top rope. Really, a flat bit................... rocknice2 wrote: edmontonalta wrote: "Best advice, set up a top rope." im climbing a waterfall from the bottom. this is about 300 meters. there are no trees for anchors. too dangerous to start from top because i cant see where the cliffs are. most people would just scramble up but i dont need any more risk in my life. i understand risk and have seen people kill themselves hiking and climbing. these are smart people so i do things cautiously. Wait til winter and ice climb that waterfall. [image]http://imgcash3.imageshack.us/Himg530/scaled.php?server=530&filename=img0078et3.jpg&xsize=640&ysize=480[/image] There is nothing here 300 meters long. Do you have any Idea of what your doing. Don't bolt that waterfall Don't bolt anything please Get some more experience That other site is about anchors not expansion bolts I will guarantee that you'll mess-up the job What kind of drill and drill bit do you have? microbarn wrote: edmontonalta wrote: http://www.uoregon.edu/~opp/climbing/topics/anchors.html Here is a helpful link. It seems like people are penalized for admitting they dont know around here. Im going to use bolts so if you know something practical please chime in. Saying you need 10 yrs experience to place a bolt is not helping anybody. The fact that you didn't already know the things in that link screams that you aren't ready to be bolting. You said somewhere that you have a four year degree and you are smart. Well, hopefully you are smart enough to realize that learning some things takes time, and some things are not self evident. Hopefully you realize that some topics are more intricate then can be addressed in a 10 minute post on some forum. If you must ascend that waterfall, find a local climber that is willing to show you the right way. There should be a few at the local gym. In the end, they will show you a cheaper, faster, more efficient way to get to the top.
all these offer sound advice and none are insulting. you might not like it, but it is sound advice from ppl that are clearly much more experieced than you are. and since you seem intent on asking for advice and then ignoring it if it doesnt fit what you thought ppl were going to say, well, you can understand that some of us get fed up with you.
i dont know what kind of person are you, but my patience only lasts this long. and as for being insulting, i never counted telling the truth being insulting. at first i thought you really had a genuine problem and watned to solve it, but you just wont be swerved from the track you have set yourself. that means that you are either ignorant (not because you wont be detered, but because you insist on doing things the wrong way) or a troll (or both). i just hope, in case you are not a troll, that you wont pay too dearly for the lessons youll learn down the road.
and if you are a troll, like other ppl observed, the beginners forum is not a place for trolling. why? because while experienced climbers can see that what you are planning on doing is really dangerous, but beginners might not. and since most beginners start their tour of rc.com (and possibly even climbing) on this particular forum, you can understand why this forum should be kept as clean as possible
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rocknice2
Aug 5, 2007, 11:59 AM
Post #52 of 70
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Registered: Jul 13, 2006
Posts: 1221
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edmontonalta wrote: You guys just insulted me and gave me zero advice. you guys are totally rude and unhelpful.
Nobody called you an idiot..........yet!
After all your posts it's clear your an over educated moron.
You have more than enough gear here to get yourself killed.
How do you plan on asending 300 meters with 3 Home Depot eyebolts???
Just you selection of hardware tells me that you have everything to learn A-Z .
How many times do we have to tell you that it's not as easy as you might think.
It may look easy when watching an experenced bolter but that's only because they have experience.
Here is what you'll need:
1 Cordless Hammerdrill 24v = $300.00 used
2 Extra batteries 24v = $200.00
3 Drillbits (carbide) = $30.00
100 SS. Expansion bolts = $250.00
100 SS. Hangers = $250.00
Aiders...............
Hooks..............
'Biners................
Slings.................
Hammer..............
Wrench...............
Are you getting the picture. Your going 300 meters that list may not be enough.
LOOK just tell us what it is you want to do and I'm sure we can help.
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dingus
Aug 5, 2007, 2:39 PM
Post #53 of 70
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Registered: Dec 16, 2002
Posts: 17398
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overlord wrote: besides, id rather risk 'humiliation' with answering a troll than risking this being for real and not trying to dissuade him
The Earnest Dissuasion, the ole ED baby! - RC.Com trademark.
That's what makes them so funny. On the off chance you were serious that is.... hah hah! (get it?)
DMT
(This post was edited by dingus on Aug 5, 2007, 2:40 PM)
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dingus
Aug 5, 2007, 2:42 PM
Post #54 of 70
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Registered: Dec 16, 2002
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stymingersfink wrote: TOS prohibits trolling anywhere on the site,
Ahhhhh the ole TOS rears its ugly head.....
always some Regulations Guy Spouting the Party Line somewhere eh?
DMT
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dingus
Aug 5, 2007, 2:45 PM
Post #55 of 70
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Registered: Dec 16, 2002
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flint wrote: Imagine that you ignorant shit head.
You may be too hard and brittle for this medium.
One word - valium.
DMT
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dingus
Aug 5, 2007, 2:47 PM
Post #56 of 70
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Registered: Dec 16, 2002
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SkaFreak wrote: edited to add: Mods, you should probably just delete this thread, or at least move it out of the beginners forum.
Followed by the inevitable call for censorship and post shuffling. I LOVE THIS PLACE!!!111
This belongs in the RC.com Hall of Fame.
DMT
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dingus
Aug 5, 2007, 2:48 PM
Post #57 of 70
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Registered: Dec 16, 2002
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overlord wrote: you are either... a) a troll or b) so blatantly ignorant that i wish you were a troll.
Ummm........
??????
DMT
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stymingersfink
Aug 5, 2007, 3:56 PM
Post #58 of 70
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Registered: Aug 12, 2003
Posts: 7250
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dingus wrote: stymingersfink wrote: TOS prohibits trolling anywhere on the site, Ahhhhh the ole TOS rears its ugly head..... always some Regulations Guy Spouting the Party Line somewhere eh? DMT
Uh, did you finish reading the rest of that thought?
In reply to: TOS prohibits trolling anywhere on the site, but especially inappropriate is the beginners forum. Much slack will be cut elsewhere, but I don't think the mod's give as much leash around this forum... thus my suggestion that rather than just leave or get himself tarpitted, he try posting to perhaps a different forum where he may prove to be amusing.
Did you notice the change in banner to the thread?
the Terms of Trolling only require that you not get tarpitted for being too blatent or offensive or whathaveyou, especially if you've got some quality shit. The concern had been raised, I just fleshed out the reasoning behind it a bit for our new friend to comprehend a bit better.
Personally, I'm still waiting to get a good laugh out of 'im, but with the start I've seen so far I don't imagine I'll have to wait till his 400th post either. If he's around that long.
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billcoe_
Aug 5, 2007, 4:14 PM
Post #59 of 70
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Registered: Jun 30, 2002
Posts: 4694
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Please don't feed the Trolls.
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TicTac
Aug 5, 2007, 4:21 PM
Post #60 of 70
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Registered: Mar 18, 2007
Posts: 20
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Im sorry but I have to chime in my two cents. I dont post often, I usually search and read the forums but listen up Guy-
Did you watch Discovery Channel and see that Bear Grylls guy climb up a waterfall?
And two, Why do you want to pollute such a pristine waterfall with your crap? Done proper or not, its polluting an area for your own benefit, not multiple climbers.
So please, listen to the more experienced trying to help you...
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SkaFreak
Aug 5, 2007, 5:36 PM
Post #61 of 70
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Registered: May 17, 2007
Posts: 53
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No, eyebolts and a drill are sitting around in everyones garage, if you're a climber it explains slings and a reverso. The hour spent drilling a hole in rock, that's just dedication.
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sky7high
Aug 5, 2007, 10:13 PM
Post #62 of 70
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Registered: Feb 15, 2006
Posts: 478
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SkaFreak wrote: No, eyebolts and a drill are sitting around in everyones garage, if you're a climber it explains slings and a reverso. The hour spent drilling a hole in rock, that's just dedication.
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billcoe_
Aug 7, 2007, 5:07 AM
Post #63 of 70
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Registered: Jun 30, 2002
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Some Notes On Bolt Glue-in bolt Design.
.
Practically bolts consist of two parts: The legs glued into the rock and the eye.
Considerations are; strength, material cost, manufacturing/tooling cost, ease of use, hole required, rock strength, durability, regulatory requirements (EN and UIAA).
Testing. The EN-959 requires a fall resistance of 25kN and an extraction resistance of 15kN,
the UIAA-123 requirements are 25kN fall and 20kN extraction.
It should be noted that bolts do not come under the catagory of Personal Safaty Equipment and therefore do not require independant testing and carry no CE mark.
In my case these tests were carried out using a hydaulic extraction tester calibrated to plus/minus 10%
All figures given below are for extraction (worst case).
Testing Equipment.
The D.A.V. tester was purpose built by the Technical University of Munich and is a hydraulic extraction system.
My tester was purpose built by myself and is also hydraulic as is that built by my friend in Austria.
The only suitable commercially available and certified tester I can locate is manufactured by Com-Ten Industries (www.com-ten.com) who produce a nice looking portable (25lbs) extraction tester rated to 2700kg for USD 2295.(Hand Operated Digital Portable Fastener Tester)
Typical test results.
Taken from Axiale Auspressversuche bei Fortbildungen der Sicherheitsforschung in Donautal und in Frankenjura 1. Deutscher Alpenverein. (available as pdf) and test result obtained by myself and collegues.
Raumer Expressanker M10 A2 ss (sliding sleeve on cone). 8 tests, 30kN, 36kN 15kN (rock failure), 30kN, 36kN, 36kN 15kN, 9kN (sleeve failed to expand sufficiently)
Our Test on similar design. 10mm Mild Steel.80mm long. 3 tests. All failed below 8kN. Bolt broke at thread.
Our Test M10 A2 ss. 80mm long. 6 tests. All withstood 36kN before bolt failed at thread.
Fischer Expressanker (similar design to above) mild steel. 75mm long. 2 tests. 35kN, 12kN (rock failure.)
Upat Expressanker (similar design). M12 mild steel. 5 tests. 37kN (rock failure), 55kN, 31kN rock failure. 50kN. 56kN,
Our Test. M12 A2 ss. 62kN.
Petzl Long Life (hammer-in) 12mm A2ss. 7tests. 23kN (extracted) 22kN (extracted) 15kN,
12kN, 13kN, 27kN,27kN (all rock failure.
Salewa Bühler Bolt. 12mmdia. A2ss. 7 tests. Long series. 52kN, 52kN, 56kN, 48kN, 27kN (last two- karabiner linking tester failed, all others glue failure) Short series.30kN (glue failed) 47kN (broke out)
Our Tests. Multiple tests (ca50). Normal straight Bühler type. A2 ss. 12mm dia hole. 6mmdia rod. 80mm long. Worst test 36kN (rock failure) 43kN (glue failure)
Improved design. Between 58kN and 72kN. (in all cases rock failure).
Ushba Bolt (Buhler type glue-in developed for Thailand to overcome the corrosion problems)
Material. Titanium:10mm dia. 5 tests. 9kN, 9kN, 10kN (all broke at eye weld), 24kN, 34kN.
Fischer Highbond threaded anchor. M12. A4 ss. 6 tests. 47kN (rock failure) 81kN, 72kN, 53kN(rock failure) 60kN, 73kN.
Own Design Lower Off . 12mmdia ss. Unable to extract from rock. Tester failed at 72kN.
Legs.
To understand the requirements for the legs it is first important to understand that stainless steel displays very poor adhesion characteristics, an often used value for epoxies to stainless is 7N/mmē, this being achieved by scrupulous cleaning and wet abrasion with 100grit abrasives and epoxy. Not a scenario likely to be seen at your local crag! Figures for epoxy bond strengths are hard to find but for example 3M produce an aerospace certified epoxy which achieves a value of ca. 11.8N/mmē in shear. This is naturally after adequate surface preperation, a typical example of which would involve de-greasing, grit blasting and de-grease/etch. (One recommended etching solution is 47%conc. Hydrochloric acid, 2% of 30% solution hydrogen peroxide, 9% formalin and 42% water applied for 10 minutes at 65°C).
Incidentally we first clean our bolts with acetone and they are then cycled through the dishwasher on itīs highest setting!
As surface preperation to the extent outlined above is impractical the UIAA feel it is nescessary to provide mechanical keying. In the traditional Bühler bolt this is achieved by applying a very rough weld between the legs. Later products, at the suggestion of the UIAA have teeth pressed into the legs, a satisfactory solution but with massive tooling costs.
We discovered that by twisting the legs through 90° the holding power was nearly doubled in comparison with the older single weld type, and subsequently I have refined this further, the latest version being twisted through720° and requiring no welding, a considerable saving in cost and time. Drop testing in Italy showed a further benefit with this construction method, instead of shock-loading the entire glue line the bolt tended to untwist, appliying a steadier loading to the glue.
The next requirement is to provide sufficient glueing area to the rock. Figures are hard to come by as most tests are in concrete and the rock types vary considerably. Our tests show that in most limestone types and using epoxy that 1500mmē is adequate, this represents a 12mm dia. hole 40mm deep. Gluing into this depth of rock can causes problems as generally rock break out will occur before the proof loads are achieved and so generally I use 80mm deep holes for a good safety margin, that all my test bolts withstand 40kN is proof of this. Depending on the rock type the DAV (German Alpine Association) recommend 80mm depth for limestone and granite and 150mm or longer bolts in sandstone.
The depth of hole is critical as the rock fails in a cone out from the bottom end of the bolt, too shallow a hole and the rock itself fails before the bolt. Practical tests in various types of limestone show a depth of 60mm gives values of around 38kN. 80mm depth gives around70kN. Another problem here is that the surface of the rock is usually weathered and has different characteristics as further in, noticably limestones are very brittle on the surface and the first 10mm or so drilled are often shattered.
Eye.
The requirements of the EN/UIAA standards call for minimums which represent the familiar Petzl bolt hanger, but these are the minimum. When designing my bolts I looked at real world climbing and designed the eye to make climbing safer and more convenient.
Safety. The eye is large enough to allow a bight of rope to be pulled throught and attatched to the harness before untieing the rope end if retreating from a route, a single figure-of-eight knot may be passed through the eye when threading to lower-off and if one is having real problems three fingers can safely be inserted in the eye. A major problem with many bent wire bolts is that if the quickdraw is pulled above the bolt the gate will be forced open by the upper leg, I therefore extended the eye to reduce the potential of this occuring.
Practicalities.
While no doubt the aircraft industry could design the perfect bolt we couldnīt pay for it, and if the rail industry designed it we certainly couldnīt pick it up so some elements of realism have to be considered, while for instance I think staples are a shocking idea (see under) full credit to the lads for putting them in, at least the routes are there and nobody has died.
Unless the bolts are to be paid for by general climbing funds instead of by a few dedicated climbers the following should be considered.
Material cost.- 8mm stainless steel costs nearly double the price of 6mm.
Manufacturing costs.- If bolt design becomes too complicated then only major manufacturers can afford the tooling and the price is correspondingly high, ergo less routes.
Ease of use-. Easier clipping, convenient retreat after failure on a route, easy threading are the benefits of a well designed bolt, none of which can be said for the Petzl style hanger.
Hole required.- In other words how many bolts can I fit from a charged battery. The requirement for around 3000mmē gluing area means whether I drill 10, 12 or16mm dia the rock removal will be the same BUT using 8mm stainless, i.e. drilling a 16mm hole, means the hole is too shallow and to get the required depth (80mm) I would have to drill twice as much hole.
Rock strength.- The advantage of Bühler bolts is that it is easy to adjust the manufacturing process to make longer bolts if needed for softer rocks, my bending jigs allow bolts of infinite length to be made.
Durabilty.- The life expectancy of the bolts themselves must be almost indefinate, the glue systems generally used have a life of at least 20yrs as long as they are compatible with the acidity values of the rock. Some problems have occured in humid climates and also in some sandstone types, there is information available on this from the D.A.V. which I will try to obtain. Important is to use glues designed for the construction industry as they try to make them ph neutral, problems have occured using other glues. Some advice from an idustrial adhesives expert would be welcome. The biggest problem with durability experienced in Germany with 6mm bolts has been the climbers repeatedly top-rope (nowdays called bottom roping I believe) routes with the rope threaded through instead of using a karabiner, over the years they wear very thin due to sand in the ropes. As regards fatigue there appears to have been no testing done, out of curiosity I am currently building a test rig to repeatedly flex a glued in bolt and will report on this later.
Regulatory requirements.-The above mentioned standards EN-959 and UIAA-123 only govern the manufacture/sale of equipment, and do not concern themselves with how the bolts are fixed to the rock, they merely say how strong they must be. Every kind of Bühler type bolt I have seen conforms to these requirements.
Staples.
You may or may not be aware that these were in common use in Germany for many years. The Germans being thorough chaps go around testing bolts at regular intervals and the results led to two decisions. 1) To remove all staples immediatly as none achieved the required test figures. 2) To recommend the removal/changing of all bolt-in bolts after 10 yrs, all new bolt-ins should be sealed against water ingress, either as in the construction industry with a rubber ring, or with a silicon sealant, and to discourage the use of bolt-ins in areas subject to freeze/thaw conditions.
The test results for staples were not published by the DAV as far as I know but we made and tested some. 8mm dia rod with 80mm legs achieved around 6 to 8 kN, When I knurled the legs to improve the bond the rock failed, generally at around 12kN. Examination of the failure showed that drilling two holes so close together seriously weakens the rock, according to friends in the quarry industry the drilling produces micro-fractures and these link up producing an area of shattered rock between the holes. (A similar effect to when you try to fit a expansion plug in a masonary wall near to an old one). Another problem we noticed was that on the bolts with bonding failure only one leg failed, implying that the load is not evenly shared, therefore the bonding for each leg must be capable of withstanding the proof load.
Incidentals.
To remove glue-ins you need a gas burner and a tin cut as a wind shield, heat the bolt to ca 130-150°C and pull it out with a wrecking bar. A fun job half way up the cliff!
If you wondered about the lower-offs, they are 120mm deep in the cliff and have an M12 thread taper cut onto them in addition to two 3mm spiral grooves to prevent rotation and allow them to be inserted. We tested one straight out with 72kN and it did not look happy but was intact and usable.
Chemically Fastened Anchors. (Glue-Inīs).
The current European standards relating to the manufacture and sale of rock anchors for climber protection are EN 959 and UIAA 123. The EN requires an extraction resistance (direct pull out) of 15kN, the UIAA 20kN. The radial loads (downwards in normal application) are 25kN for both standards. A pictorial representation of these standards is shown below, for copyright reasons it is not possible to give the full text.
Bolt Types.
Currently there are three main types of glue-in bolts in use. All are manufactured of stainless steel to conform to the corrosion requirements, the usual material being AISI 304 (A2)
Forged Eye Bolt.
Various manufacturers, the one shown is a Petzl Collinox, the smaller of the two models they make and a fine product. 10mm dia shank grooved for better adhesion. Expensive forging tools put the price out of reach for equipping a large number of climbs, at 12.90 a go + 1.75 for the glue ampoule I doubt you will be clipping many of these. The larger Batínox for soft rock comes out at 23.90 + 3.50 for the glue!
There have been a number of welded eye bolts on the market but weld failures have always been a problem, it is unlikely that the standards authorities would certify them nowadays. The only one on the market (not in Europe) that I know of is the USHBA bolt made from titanium, in tests by the German Alpine Association (D.A.V.) three out of five broke at the weld at under 10kN
The Bühler Bolt.
Developed by the late Georg Bühler, a well known pioneer climber and engineer from the Frankenjura in Germany. Problems with the staples previously used led him to design this bolt for easy home manufacture and they are universal in the German speaking climbing world. The best bolt for home constuction and a big advantage is that it is simple to extend the leg length to suit soft rock. Either from 6 or 8mm dia stainless steel rod. (the 6mm rod can have wear problems if used for lower-offs but otherwise is easily strong enough). Usually 80mm long legs for limestone and up to 150mm for sandstone.
Shown is a home made bolt with a particularly large eye made from 6mm stainless. Note the large and rough weld, this is needed to provide resistance to extraction as the glues adhere very poorly to stainless steel. Material costs ca 0.40.
This is a commercially made bolt (from Austrian Alpine) using 8mm rod forged down to give a 12mm shaft with teeth to provide adhesion. Cost 4.95 + glue. Note the curved shape of the upper part of the eye introduced to reduce the chance of involountery unclipping.( see below)
Along with an Austrian climber I tested a lot of variations of the Bühler bolt and we found that twisting them through 90° nearly doubled their holding power. The latest generation I make is shown below , being twisted 720° gives exceptional holding power and without the need for welding. 6mm dia AISI 304 stainless steel. Shaft length 80mm.
The Staple or U Bolt.
The easiest to make but many countries have reported problems with this type, the originator stopped making them over 30 years ago. As noted in the first section many national federations recommend against their use and there are none commercially available, the problems with staples are also discussed there. This is one with threaded legs for better adhesion and extremely wide leg spacing I made up for testing some years ago.
A fourth kind of anchor is available, basically a threaded bar but as this requires a hanger as well has not proved popular with climbers, it is easier to use a normal bolt-in.
For and Against Glue-in bolts.
For. Strong. Durable. Thief proof. Smooth eyes allow safe rope threading for retreat. No corrosion due to dissimilar metals.
Against. Usually require larger hole than a bolt-in. Akward to fit on very steep climbs. Cannot be placed on lead. Messy, complicated gluing procedure. Need correct temperature for glue cure.
Glueing.
Regrettably not as simple as many would think. Various adhesives derived from the construction industry have been used; polyester, vinylester, epoxy and, while not strictly an adhesive, quick setting cement.
One problem is that the manufacturers do not normally write on the packaging what the glue is and sometimes it takes a lot of research to actually find out, a good indicator is however the price as epoxies are usually at least twice the price of the others, currently around 28 per 300ml tube.
Most climbers nowadays are using vinylester/polyester due to its price and convenience, while not so strong as epoxy the mechanical nature of the gluing rather than adhesion and rock failure make this not so important. We have tested many Bühler type bolts with these adhesives with satisfactory results. I fitted around 2500 bolts in Greece using epoxy for practical reasons and for the rest of this article the glue described is epoxy and all test data is with epoxies.
(Quick setting cement has been used for a long time and has a good reputation though I have seen no test data, the main problem with it is the setting time, you have to hang on the rope, mix it up and poke it into the hole in a very few minutes, not easy I can assure you. I intend to test some this year to get some comparison figures).
Application.
Epoxy glues are available in three forms, bulk, 310ml self mixing cartridge and glass or plastic ampoules. Bulk has the advantage of cheapness and guaranteed mixing quality but injection into the hole and working time can be problematic, I mixed batches of around 300 ml (depending on the number of bolts to be glued) and used a grease gun to inject it in the holes, due to the high temperatures in Greece (+35°C) it was an advantage to keep the epoxy cool with ice packs before mixing allowing a working time of about 30 minutes. For large numbers of routes on a sport crag it is the best way but takes some organising. ( I have fitted around 2500 bolts this way so far). Cartridges are the choice of most climbers but are about threee times the price and the cartridge guns can be very expensive to buy along with the mixing nozzles. These are unfortunatly not as reliable as one would hope and every bolter can tell you about blocked nozzles causing mixing failure. Ampoules, whether glass or plastic are the most convenient way and therefore the most expensive, problems arise when they are not compatible with the bolt design, most requiring the bolt to be rotated rapidly to mix the glue correctly which is not usually practible.
Polyester and vinylester come in cartridges, usually 310ml or 380ml with mixing nozzles, unfortunatly the mixed glue in the nozzles hardens within a few minutes so the routes must be prepared (drilled and cleaned) and then bolted in one go, carrying a spare nozzle or two is a good idea! We are currently getting about 30 to 35 bolts per 380ml cartridge using 80mm long Bühler bolts and a 13mm hole giving a glue cost of around 0.30 to 0.40 per bolt.
Successful Gluing.
The main factors are cleanliness, correct mixing, distribution, temperature and glue line.
Cleaning- obviously the bolt should be clean but due to the mechanical nature of the joint (see details in the bolt design section) this is not as critical as hole cleanliness. The hole should be blown and brushed out and dry, damp and dusty holes can cause a loss of up to 30% of strength.
Correct mixing should be a matter for the designers of the mixing nozzles if one is using the normal cartridge system but experience from other climbers has shown that a bit of help can be needed, stirring the glue in the hole with a thin metal rod seems to be the best way. A careful eye has to be kept on the nozzles to check they have not got blocked causing the wrong proportions of glue/hardener to be delivered. With ampoules care has to be taken to follow the manufacturers instructions on any nescessary rotation required to achieve adequate mixing. Using bulk epoxy one has the advantage of being able to control the mixing process exactly and one always has a sample of the last batch in the mixing container to check that it is cured. Unfortunatly the mixing can only practicably be done at the foot/top of the climb.
Distribution means that the glue should contact all the surfaces of both hole and bolt, as the hole is normally partially filled with glue from the bottom to prevent air bubbles and the bolt inserted there are two ways to ensure complete coverage, either design the bolt with channels or grooves to force even distribution or to rotate the bolt as it is inserted, most commercial chemical fasteners call for rotation using an electric drill to ensure correct distribution and mixing. This is one failing of the staple as it cannot be rotated and in tests large air bubbles have been found on the shafts with obvious implications for their strength.
Temperature is not normally a problem in that most construction adhesives are designed to be used at normal building site temperatures which are the ones at which most climbers are active. So long one is in the temperature range specified then all is good except that when it is cold full cure can take a very long time, high temperatures mean that working times are short and more mixing nozzles may be required but I have bolted for many years in temperatures up to 40°c without difficulties apart from the need to be well organised due to the short working time.
It is important that the glue does not get too cold (i.e. near freezing) before curing as this stops the reaction!
Glue Line-or better described by some authorities as Critical Glue Mass, is often overlooked but is very important (I have tried to simplify this to make it easier to understand). Epoxies and esters are exothermic, that is they require heat to cure and therefore they rely on the fact that they can raise their temperature (normally to ca 65°c) faster than this heat is conducted away by their surroundings. Placing a relatively large metal bar in the glue is obviously not the ideal situation as it will conduct the heat away and prevent full cure, for this reason most manufacturers call for a hole 2mm larger than the object to allow a thick enough glue line or glue mass and therefore an adequate heat build up and cure. Interestingly this effect was also discovered in the early 80īs in the timber industy and they also recommend a 1mm glue line when embedding metel fasteners. A problem is then to ensure the glued object is in the centre of the hole, commercially this is done by various methods, the most obvious is the perforated plastic sleeve often supplied with chemical fasteners. Another way is to supply the glue in a glass cartridge which is designed to break up and act as a spacer/filler, a third way is to give the bolt a shape in which parts of the bolt are large enough to centralise while the rest is left for the glue, typically this is the approach used by Bühler bolts and by the newest Hilti chemical anchors. The illustration of the Petzl bolt above shows this clearly, the neck of the shaft is larger than the rest, they are also supplied with glass ampoules.
Cure Time
Varies depending on the glue type, most construction glues have a cure time of around 3 hours but they usually achieve their full strength after a long period. I tested a steel-setting epoxy at around 20°C by placing 7 bolts and testing one every 24 hours, after 24 hrs the bolt failed at 12kN, 48 hrs 22kN and it took 3 days to achieve full strength 38kN (rock failure).
The poly- and vinylester are faster but I have not perfomed this test on them. I wait at least one day before climbing the route!
Hole Depth/Bolt Length.
The main factors concerning the bolt length and thus hole depth are a) to provide sufficient surface area for the glue and b) preventing rock break out.
a): The adhesion to the rock varies to an extent with the rock type, in the limestones we have tested a depth of 40mm with a 12mm hole gives sufficient area to withstand 25kN, giving an area of 1508mmē, however the problems outlined in b) render this somewhat superflous as this area will normally be exceeded.
b) When loaded a correctly designed bolt will fail when the rock breaks out. The failure is generally as a cone shape starting at a point about half way down the shaft or nearer the end and the depth of this failure and hence the strength of the bolt is related to the hardness and therefore strength of the rock.(There is a useful table available from Hilti giving various rock types and strengths related to concrete proof samples).
Our tests in limestone show a depth of 60mm will withstand around 30kN, 80mm will withstand around 40kN and 120mm will withstand over 72kN ( we were unable to apply more load, at this point a 6mm bent rod bolt would fail anyway.) Other tests show similar results, there being some debate as to whether hole depth to strength is a linear function or not though theoretically this should not be so.
A comparison test by the German Alpine Association on various rock types resulted in recommending 80mm depth for limestone and granite (they give a figure of 35kN for this which corresponds well with our data) and up to150mm for soft sandstone.
It should be remembered that weathering of the surface affects the outer layer of rock, generally they appear harder than the rock inside and most people discount the first 10mm or so as being unreliable, the sandstones and limestone being particulary suspect.
The concensus of opinion appears that a depth of 70 to 80mm is satisfactory for hard/ medium strength rocks and around 120mm for soft rock.
Edge Effect.
If a bolt is placed too near the edge of the piece of rock or near a crack/fault the loading of the bolt will cause the rock to break out in this direction at a relatively low load. There has been much research into this and the general recommendation is not to place a bolt within 200mm of the edge, some go as far as 400mm. Unfortunatly when using the staple type of bolt the action of drilling a second hole creates this edge and the cones of failure overlap, seriously reducing the load bearing capability. The fastener company Hilti recommend a hole spacing of twice the hole depth for adjacent fasteners to avoid this problem. ITW Ramset give a hole spacing of 1.5 x depth as the critical spacing and a distance of 1.25 x depth from an edge. The UIAA recommend a spacing of at least 200mm when fitting two bolts at a belay.
Bolt Design.
Eye.
The minimum dimensions for the eye are given in the EN/UIAA norms, unfortunatly they seem to be a little outdated as the modern generation of karabiner with a forged T profile take up so much room that it is hard to fit a second karabiner in the eye. The Salewa manufactured Bühler bolt is a particular offender in this respect, some of the older Petzl hangers also can be annoying, the only solution being to carry some quickdraws with older bent wire karabiners.
For makers of bolts the solution would appear to be making the eye larger but very quickly the problem of involuntary unclipping raises its head. As the climber passes the bolt rope drag tends to lift the quickdraw and the effect illustrated below can occur (and has, with fatal results).
As one can see the lifting action of the quickdraw causes it to unclip, in this case in a simulated staple with a leg spacing of 35mm.
To reduce this effect the leg spacing or eye diameter must be kept down to around 15mm which rather precludes fitting a second karabiner or double-threading the rope in order to lower-off.
Another approach, which I use, is to increase the eye size to the extent that the the karabiner cannot unclip, the legs or eye needs to be about 60mm across for this to function as illustrated below. This eye size has several other benefits, if the climber grabs hold of the bolt they can insert 3 fingers into it reducing the likelyhood of severe injury if they fall, in addition if it nescessary to retreat from a route the rope can be threaded through doubled to clip into the harness before untieing, an obvious safety point. The only objection to this type of eye is an aesthetic one but they are no more intrusive than a typical plate hanger and a lot less than a dead climber at the bottom of a climb!
A third way to prevent unclipping would be to manufacture a bolt with more than one small eyes but I know of no bolts so produced, some Bühler bolts were produced with a bar welded across to achieve this effect but doubts about the action of welding on the integrity of the bolt led to this being dropped, most climbers were observed to clip the larger upper portion anyway rather negating the effect.
Other sections of the norms regarding the eye concern themselves with material thickness and edge radii to prevent karabiner damage, none of which present any difficulties with the types of bolt described here.
Bolt Shaft or Legs.
Apart from being strong enough to withstand the loading which normally is easy to achieve the bolt stem must be so constructed or prepared to provide satisfactory bonding to the glue or a mechanical key! The ahhesives used in the building industry are primarily configured for mechanical loading and as such have very low bonding ability, so low in fact that they can be discounted, using epoxy adhesives and excellent surface preparation a value of 7N/mmē can be achieved and at aerospace standards 14N/mmē but with the adhesives in common use these levels are unobtainable. Surface roughening helps but is not enough, one test on a typical staple showed an improvement of 6kN. Either the bolt needs forged teeth to embed in the adhesive or needs some other shape to prevent extraction, some variations on this are shown in the illustrated bolts. A thread of 1mm depth is often used being a standard metric thread but whether this is the optimum is not known, it does however give satisfactory results. The testing laboratory I used in Italy (for UIAA certification) stated they would not test any bolts without any form of mechanical keying on the shaft, even the older type of Bühler bolt with one end weld was not considered satisfactory. (The difficulty being if the weld was big enough to prevent pulling through the glue then it would prevent the glue flowing around the bolt when inserted, this being the reason I developed the twisted design to allow good glue distribution).
For those of the a few angle grinder cuts in the legs will do school of thought here is a photograph of one of two bolts recovered after being ripped on a sport route in Hollental, Germany. The climber fell on the bolt after a hold broke, ripped it and the next and decked suffering severe injuries. The accident was reconstructed and the load calculated at 5 to 7kN. The glue was analysed and found to be fully cured and satisfactory but you can see for yourself how well it stuck to the bolt!
(Taken from Hakenausbrüche beim Klettern. D Stopper. Leader Safety Research, Deutsche Alpine Verein. First published in Panorama April 2001)
Long Term Durability.
The general concensus seems to be that glued-in bolts have an almost indefinate life span. The D.A.V. tested some older bolts (up to 15yrs) and found no loss in strength. The glues themselves when cured are chemically inert and should not degrade. The glues used in the construction industry have an expected life span of at least 20yrs. A2 stainless steel has proved to be a reliable material in the marine environment and it is hard to foresee any real improvement to be made, A4 being rather more difficult to work and more prone to work hardening. The main problem with durability has been climbers persistently top-toping threaded directly through the bolt, depending on the area and use after 10 to 15yrs they get pretty thin! The only cure for this is much thicker bolts at the lower off or the use of loose rings, I personally manufacture my lower-offs from 12mm bar for this reason and also for smoother rope running.
An interesting point was raised on a recent UKClimbing forum was about the difficulty of recording and tracking the date and details of bolts fitted in order to perform constructive long term testing. The climbing committee in the Elbe sandstone region of Germany has been carefully logging every bolt fitted for over one hundred years in the largest climbing area in the world with around 20,000 routes without the benefit of computers, surely it should be possible generally to do this nowadays in order to establish some kind of database?
There has been some debate about bolt durability at coastal locations and the UIAA are considering a new standard for this, an article published by the UIAA in 2000 discusses this but does not give details of glued-in stainless bolts, the concerns appear to be regarding stress corrosion cracking in bolt-ins, a phenomenon not unknown in the marine industy. As long as the bend radii in the bolt are relatively large this should not present a problem for most of the glue-ins I have seen as they are not under permanant stress.
Lower-Offs
A difficult subject with many solutions being used in the past. At the risk of being controversial the subject is not helped by the UIAA standard which in my opinion fails to address many of the problems with lower-offs and ignores the realities and practicalities of climbing.
For myself and most climbers I know a lower-off needs to be strong, easy to use, safe and durable.
Strength- The UIAA allow lower-offs to be weaker than normal bolts, the reasoning being that they are not subject to leader falls, however climbers do strange things and I have seen leader falls on lower-offs. My thinking is that they should be as strong as belay bolts and can then be used on multi-pitch routes as belay/abseil points as well, basically my feeling is everything I fit in the rock must hold 25kN as I have no control over its later use.
Easy to use- Preferably one handed.
Safe- There two aspects to be considered here; a) fitting the rope in without endangering the climber, and b) the rope remains in place no matter what the climber does later.
* Either the climber threads through or clips/ hangs the rope in.
For threading through the eye should preferably be large enough so that a bight of rope can be pushed through and knotted, to be clipped with a screwgate to the belay loop of the harness before untieing the end, thus the climber is never detatched from the rope. (One reason I make my bolt eyes so large).
Clipping or hanging the rope in is faster and easier but can lead to plenty of problems as discussed below.
b) The UIAA standard requires that to remove the rope from the lower-off the climber must move part of it, the implication being that some sort of clip or sleeve is used, unfortunately in the real world these moving parts become immovable or damaged as anyone who has struggled with seized up old krabs at the top will know. Most of the lower-off s designed in this way , even if in good condition, have the problem that either by climbing above and falling or because of whiplash in the rope can allow the rope to become unclipped. I use another approach similar to the pigs-tail system which has no moving parts and ensures that when in place the rope cannot come out no matter what happens, with this design the complete lower-off is a one-piece glued in fitting without the attendant problems of welding. Being made of 12mm bar they are immensly strong and rope wear and damage is not an issue, they are also able to be made without specialised tooling and are therefore financially within the reach of most bolters.
Durability- After many years of use wear from the rope, and particularly grit in the rope, causes a groove in the lower-off eventually weakening it, especially if the route sees a lot of top-rope activity. One way to prevent this is using a loose ring which should rotate and therefore distribute the wear, not my favourite idea as I donīt trust welded rings that much! The approach I favour is to make the lower-off so massive that weakening will not be a problem in the lifespan of the bolt (over 20yrs?), therefore I use 12mm bar.
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billcoe_
Aug 7, 2007, 5:08 AM
Post #64 of 70
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Registered: Jun 30, 2002
Posts: 4694
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That was a copy and paste thing.
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billcoe_
Aug 7, 2007, 7:29 PM
Post #67 of 70
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Registered: Jun 30, 2002
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stymingersfink wrote: billcoe_ wrote: That was a copy and paste thing. Really? How about with a reference? [:)
Sorry: http://climbargolis.com/Glue-inBoltDesign.htm
I gotta believe that the Original Poster (OP) is still reading my post 2 days later trying to sort it out. Stymingersfink, my take: this dudes definitely diabolical and deep. Not many can pull off looking so stupid that easily.
OP: I say go for it dude. Not many people can really crowd up so close to death. Don't forget to bring yer moms clothesline to tie off on something and keep yourself off the deck.
let us know how it goes.
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the_climber
Aug 15, 2007, 4:04 PM
Post #68 of 70
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Registered: Oct 9, 2003
Posts: 6142
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Hey Troll... uh, Edmontonalta.
Look, you are either a really bad troll, or just plain out there.
First your "drill" won't do it.
Second, your "bolts" will kill you at best or someone else at worst.
Third, steel and rock are different mediums! Different bit different drill; different "know how" are needed.
Fourth! Edmonton, eh.... where exactly are you finding "Granite". 4+ hours to the north would be the closest I can think of. You don't seem to indicate that it's that far... You might want to take Geology 209 "rocks for Jocks" again... or perhaps consult someone with more knowledge on, hmmm, everything to do with climbing. If it's a "waterfall" you are planning on "ice climbing" you won't need a single bolt.
Go learn something from someone who knows their shit... you're wasting bandwidth here.
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trenchdigger
Aug 15, 2007, 5:15 PM
Post #69 of 70
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Registered: Mar 9, 2003
Posts: 1447
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edmontonalta wrote: how does it hurt to answer if water freezing and expanding in the hole will cause cracks?
I can answer this one... The water freezing and expanding in the hole can cause microfractures - the single most common cause of climbing deaths. I suggest you search the forums for more info about the dangers of microfractures.
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stymingersfink
Aug 15, 2007, 11:03 PM
Post #70 of 70
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Registered: Aug 12, 2003
Posts: 7250
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thanks, I was wondering where that came from. Figured I might be able to mine the site for more good info..
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