From pistol@io.org Tue Jul 25 17:00:42 EST 1995 Article: 6220 of rec.climbing Xref: news.nsw.CSIRO.AU rec.climbing:6220 Path: news.nsw.CSIRO.AU!news.dmpe.CSIRO.AU!mel.dit.csiro.au!merlin!harbinger.cc.monash.edu.au!simtel!noc.netcom.net!news.sprintlink.net!howland.reston.ans.net!agate!news.mindlink.net!vanbc.wimsey.com!io.org!NewsWatcher!user From: pistol@io.org (Peter Chatterton) Newsgroups: rec.climbing Subject: Re: Drilling holes for bolts in wet sandstone Date: 18 Jul 1995 22:19:11 GMT Organization: Internex Online, Toronto, Ontario, Canada (416 363 3783) Lines: 38 Message-ID: References: <3ufble$8eh@newsbf02.news.aol.com> NNTP-Posting-Host: dyna-7.net7a.io.org In article <3ufble$8eh@newsbf02.news.aol.com>, namelss@aol.com (NAMELSS) wrote: > Just wondering if.... > > If drilling holes for bolts in wet sandstone is a good or bad idea? It > seems like it would be a good idea cause the rocks softer, yes I know, you > wouldn't want to put the bolts in till the rock dried out, so therefore it > would be easier on you and the drill? Would the "wet" drilling jeopardize > the strength of the bolt when you did place it? Just wondering! > Aaron As a stonemason and a climber I have some familiarity with the workability of sandstone. My response to your query is that first, the rock is not any softer wet than dry. If the stone is soft when it is wet, then it is probably powdery, spalled or decayed when it is dry, slightly different properties but equally soft or unstable. Although sandstone, like limestone is relatively porous, it is nonetheless not made softer by the water, it merely absorbs it. Of course over considerable time this absorption can lead to decay, but if you immerse a piece of sandstone in water 24 hours later it will not be any softer. In short, if the rock sucks when its wet, it's going to suck when it's dry too. Second, wet rock is better to drill into than dry rock due to the cooling effect of the absorbed water on the carbide bit. Again this is only true of porous rock, i.e. not granitic etc. The cooler the drilling operation, the less likely is cracking due to the heat generated while drilling. Drilling will also almost certainly create enough heat to vapourize all the absorbed water around the diameter of the hole by the time you are finished drilling, allowing you to place your expansion bolt or glue cartridge fastenings immediately after drilling. So wet drilling is better, but watch the ground, your electrical ground that is! Cordless is safer. Third, for the record, I have the know-how for bolting routes and am willing to pass it on, but personally I do all my drilling and fastening at work and save what's not quarried to nature for as long as possible. Just a thought. From rtgimp@aol.com Tue Jul 25 17:01:43 EST 1995 Article: 6257 of rec.climbing Xref: news.nsw.CSIRO.AU rec.climbing:6257 Path: news.nsw.CSIRO.AU!mel.dit.csiro.au!merlin!harbinger.cc.monash.edu.au!simtel!news.sprintlink.net!uunet!in1.uu.net!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: rtgimp@aol.com (RTGIMP) Newsgroups: rec.climbing Subject: Re: Drilling holes for bolts in wet sandstone Date: 18 Jul 1995 22:34:19 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 19 Sender: root@newsbf02.news.aol.com Message-ID: <3uhqvb$su5@newsbf02.news.aol.com> References: Reply-To: rtgimp@aol.com (RTGIMP) NNTP-Posting-Host: newsbf02.mail.aol.com This is a copy I sent.................. Aaron- If you speak of desert sandstone, the idea sounds really bad. When the rock is wet, a paste forms from the rock dust and makes drilling difficult. In soft rock it is also best to place drilled 1/2" angle pitons in modified 3/8" holes. Not only does the hole need to be drilled, but the hole must be "machined" in the form of a triangle to accept the pin. When placing the pin (or a bolt in harder stone) all dust must be cleared to avoid comprimising the strength. If the sandstone is harder, (ala Eldorado Canyon or Seneca, New River and other eastern sandstones in which bolts can be used) I think the dust/paste problem will still exist. I don't know if sandstones in Kentucky routinely use pin or bolt perma anchors, but the conditions above still apply. In any case, bolt placement is the single most serious ethical decision a climber makes. Don't drill unless you have been given first hand instruction, and don't try to learn this from a magazine or book. Too many holes are a bad thing contrary to popular opinion. Any more questions just ask. Gimp