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[svn r6525] Misc edits. Moved 76.htm into the 76 directory. Added some material to the rigging handbook. Fettled intro pages. Added a link to the new 204 glossary page.

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handbook/rig/boltin.htm
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<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>CUCC Expo Rigging Handbook: Artificial belays - bolts</title>
<title>CUCC Expo Rigging Handbook: Placing bolts</title>
<link rel="stylesheet" type="text/css" href="../../css/main2.css" />
</head>
<body>
<h2 id="tophead"> CUCC Expo Rigging Handbook</h2>
<h1>Bolt belays - placing and using</h1>
<h1>Bolt belays - placing</h1>
<p>Most people on Austria expeditions will be familiar with the use of bolt
belays from trips in the UK. In Austria, caves already explored will have
bolts with the hangers removed, which can be quite hard to spot. Anyone
hoping for a join-the-dots trip will be disappointed. These bolts can usually
be found fairly easily by anyone familiar with expo rigging, <i>provided a
good rigging guide was drawn up by the previous explorers</i>. Y-hangs are
common at pitch heads, so check that you find both bolts. Lower down, it is
as well to know whether a bolt has been placed for a rebelay or a deviation,
as it may not become obvious which until some way down the pitch. Such a
rigging guide is also useful to show which existing bolts should <b>not</b>
be used. Inevitably some bolts will be badly placed, or may become damaged.
It is as important not to use these as it is to find the right ones.</p>
<p>Once you've decided where to put your bolt, you have to actually physically
place and set it. The methods used differ substantially depending on whether
you are using hand bolts (spits) or Hilti HKDS's.</p>
<p>For new pitches when, as is often the case, good natural belays are
scarce, you must place one or more bolts yourself. Doing so puts you in
a position of responsibility both for the safety of future users of that
bolt and for the conservation of the cave. The aim should always be to
put in good bolts which will contribute to a safe rig with a minimum of
further bolting needed.</p>
<p>Before you actually start drilling, it is wise to flatten the surface of the
rock around the bolt site. This allows the hanger to lie flat against the rock.
Different types of hanger have different footprints; bollards have almost no
footprint at all, rings and bends somewhat more, and twists a great deal.
Remember, of course, that the next person who rigs the pitch may well use a
different type of hanger from the one you happen to have handy, and that the
club only has about ten bollards left! When dressing the rock, use the pointed
end of the hammer and tap gently, so as not to crack the rock below the
surface.</p>
<p>This is easier said than done, and there is ample evidence of this in
caves CUCC have explored over the years. The best place for a bolt may
be far from obvious until the pitch has been descended. Or maybe the best
place is obvious, but that place is hard to reach. It is tempting to try
to reach for the best placement, but overstretching or an insecure perch
may lead to a poor bolt in the perfect place. This is very much to be
avoided, since it is now impossible to put a good bolt in the perfect
place - the rock around the first placement will have been stressed and
another bolt should not be placed closer than about 20 cm from it.</p>
<div class="onleft"><a href="../l/bosch.htm"><img
alt="(73k image)" src="../t/bosch.jpg" width="200" height="200" /></a><p
class="caption">Using the Drill</p></div>
<h2>Hand spits</h2>
<div class="onleft" style="clear: left"> <a
href="../../smkridge/161/l/boltin.htm"><img alt="(36k image)"
src="../../smkridge/161/t/boltin.jpg" width="113" height="152" /></a> <p
class="caption">Bolting by Hand</p> </div>
<h3>Placing bolts</h3>
<p>Old-style hand-drilled spits are self-drilling; the spit sleeve functions
both as a drill bit and as an anchor. Screw it firmly onto the driver and tap
it gently against the surface of the rock, turning it around slightly between
each tap and removing it to blow dust away every half dozen blows or so. (You
should also tap the spit itself gently to free dust compacted into it). Once
the hole is established you can begin to hit a bit harder, but don't overdo it;
the idea is to powder the rock at the point of the spit without setting up
cracks through the rest of the rock which will weaken it.</p>
<p>Placing a bolt is a simple matter of drilling a hole and inserting a rock
anchor. The bottom end of the rock anchor is expanded by some mechanism,
and thus grips tightly in the hole, resisting any attempt to pull it
out. The anchor is strongest if loaded at right angles to its axis, ie.
parallel with the rock surface. Hence for a vertical pitch, it is normally
best to place the anchor in a vertical rock surface.</p>
<p>Watch out for the spit <i>cratering</i>; this is when flakes of rock crack
away around the rim of the hole. A severely cratered spit is greatly weakened
as the end of the sleeve is not supported by the rock. With some types of
hanger (bollards and Clowns) it is possible to drive the spit in a bit further
into the bottom of the crater, particularly if the rope is thin, but this
renders it almost impossible to use other types of hanger with that spit.</p>
<p>The hole may be made in either of two ways. For the penalty of carrying
considerable extra weight, a cordless power drill is the quickest way to
drill the hole. The heaviest item is the drill battery, which must, of
course, be removed from the cave each time it needs charging. This method is
of the most use where a lot of bolts need to be placed on a pitch series
relatively accessible from an entrance. Lots of bolts are also needed for
climbs up or exposed traverses to reach inaccessible passages.</p>
<p>There is normally a line around the driver stem around 3mm above the thread;
keep drilling until this point is reached. (This typically takes around 15-20
minutes of drilling). Now grab yourself a cone, put it in the end of the spit,
and hammer it back into the hole. You can normally detect when it is fully set
by a change in the tone of the sound when you hit it; it should rise gradually
to a high ring. If the hole is the right depth this will coincide with the spit
being flush with the surface. Now you can remove the driver and screw in a
hanger, and Bob's your uncle.</p>
<p>The older (and more reliable, but slower) method is to use the anchor
itself as the drill bit, driven in by use of a hammer. 8mm self-drilling
rock anchors have teeth around their bottom for this purpose. The anchor is
attached to a bolt driver, which is then repeatedly pounded with a hammer,
whilst rotating the anchor by hand every couple of whacks. When this gets
a little stiff, the anchor is pulled out of its hole and the dust and rock
chips blown out. The process is repeated until the top of the anchor is
just below the rock surface. A small conical "wedge" is then inserted into
end of the anchor (thin end into the anchor) and the pair put back in the
hole. Three or four good hard whacks with the hammer "set" the anchor by
driving the wedge into the bottom end, expanding it. Beware of hitting it too
many times, as this will start to weaken the rock around the anchor.</p>
<h2>Power-drills and Hilti anchors</h2>
<p>The hole produced by the power drill is a different shape from that produced
by hand - since the power drill bit has a pointed end. It is also quite
difficult to get the depth of the hole exactly right. For this reason, if a
self-drilling anchor is set into a powerdrill hole, the wedge will not be
driven into the anchor and an unsafe placement will result. To use a
self-drilling anchor, it is best to under-drill the hole, and finish off to
just the right depth, and a square hole-bottom with a hand driver.</p>
<div class="onleft"><a href="../l/bosch.htm"><img
alt="(73k image)" src="../t/bosch.jpg" width="200" height="200" /></a><p
class="caption">Using the Drill</p></div>
<p>More efficiently for power-drilled holes, use a form of anchor specially
intended for these holes. These anchors use a smaller hole, so you get more
holes for your money from one battery charge, and the design of anchor means
that the bottom of the hole is not used in the setting process, and the depth
of the hole is therefore less critical (as long as it is deep enough that the
anchor goes right in!)</p>
<p>Since the first cordless hammer drills made an appearance on Expo 1990
thanks to sponsorship from Bosch, drills have been enthusiastically adopted as
the best solution for large-scale bolting tasks; some of the fun and games of
recent years, like the 21-bolt traverse over Gaffered to the Walls in 2003,
would be unthinkable with hand bolts. However, drills are not suited to use
with ordinary spits, as the setting process depends critically on the bottom of
the hole being flat. It is possible to drill a hole part-way with a power drill
and finish it off by hand, but this is tedious.</p>
<p>Hence we have found it easier to use Hilti anchors, which are specifically
designed for use in drilled holes.</p>
<div style="text-align: center">
<a href="../../years/1990/hilti1-300.png"><img
@@ -102,6 +82,32 @@ src="../../years/1990/hilti1-100.png" /></a><br />
width="220" height="94"
src="../../years/1990/hilti2-100.png" style="margin: 10pt" /></a></div>
<p>There are two versions of these bolts, the HKD and the HKDS. The latter are
easier to use, as they have a "shoulder" around the top of the bolt which sits
against the rock, meaning that the depth of the hole is not important.</p>
<p>To place a HKDS, drill the hole in the obvious manner until it is deep
enough for the bolt to sit in without touching the bottom. If in doubt, drill
it deep! When the hole is deep enough, grab a setting tool and start bashing it.</p>
<p>Start with very gentle taps. The reason for this is so the shoulder can hold
the bolt in position until it begins to grip the sides of the hole; if you
start by smashing it with all your might, the shoulder will bend and the bolt
will disappear, useless, into the depths of the hole. Once it has some grip you
can start hitting a bit harder.</p>
<p>It is very important to hit the Hilti setting tools exactly square, as they
are made of very hard steel which is rather brittle and hence it is easy to
shear the end off. When the bolt is fully set, you should be able to see marks
on the shoulder of the spit from the four little teeth on the collar of the
driver; don't worry if you can't see all four setting marks, but aim for two at
least - one can easily be a consequence of leaning the driver over too far to
one side.</p>
<p>Sometimes, in particularly hard rock, it can be impossible to get the
setting marks. Use your judgement; if you're not making any progress despite
sustained hammering, it's probably OK to stop!</p>
<hr />
<ul id="links">
@@ -110,7 +116,9 @@ src="../../years/1990/hilti2-100.png" style="margin: 10pt" /></a></div>
<li><a href="index.htm">Rigging Guide</a>
<ul>
<li><a href="intro.htm">Introduction</a></li>
<li>Bolt belays &ndash; placing &amp; using</li>
<li><a href="boltplace.html">Choosing bolt locations</a></li>
<li>The mechanics of placing a bolt</li>
<li><a href="exporig.html">Expo-specific rigging tricks</a></li>
</ul></li>
<li><a href="../look4.htm">Prospecting guide</a></li>
<li><a href="../survey/index.htm">Surveying guide</a></li>

4
handbook/rig/index.htm
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@@ -25,7 +25,9 @@ expedition work, and some will cover techniques very rarely seen at home...</p>
<ul>
<li><a href="intro.htm">Introduction</a></li>
<li><a href="boltin.htm">Placing bolts</a></li>
<li><a href="boltplace.html">Where to put your anchors</a></li>
<li><a href="boltin.htm">The mechanics of placing bolts</a></li>
<li><a href="exporig.html">Expo-specific tricks</a></li>
<li>well, that's all so far...</li>
</ul>

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handbook/rig/intro.htm
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@@ -123,17 +123,19 @@ rebelay will result in a high fall-factor if the belay fails.</p>
<hr />
<ul id="links">
<li><a href="../index.htm">Expedition Handbook</a> &ndash; Contents
<li><a href="../index.htm">Expedition Handbook</a> - Contents
<ul>
<li><a href="index.htm">Rigging Guide</a>
<ul>
<li><a href="intro.htm">Introduction</a></li>
<li><a href="boltplace.html">Choosing bolt locations</a></li>
<li><a href="boltin.htm">The mechanics of placing a bolt</a></li>
<li><a href="exporig.html">Expo-specific rigging tricks</a></li>
</ul></li>
<li><a href="../look4.htm">Prospecting guide</a></li>
<li><a href="../survey/index.htm">Surveying guide</a></li>
<li><a href="../rescue.htm">Rescue guide</a></li>
<li><a href="../photo.htm">Photography guide</a></li>
<li><a href="index.htm">Rigging guide</a> &ndash; Contents
<ul>
<li>Introduction</li>
<li><a href="boltin.htm">Bolt belays</a> - placing and using</li>
</ul></li>
</ul></li>
<li><a href="../../infodx.htm">Index to info/topics pages</a></li>
<li><a href="../../indxal.htm">Full Index to area 1623</a>
@@ -141,7 +143,6 @@ rebelay will result in a high fall-factor if the belay fails.</p>
<li><a href="../../areas.htm">Area/subarea descriptions</a></li>
</ul></li>
<li><a href="../../index.htm">Back to Expedition Intro page</a></li>
<li><a href="../../../index.htm">Back to CUCC Home page</a></li>
</ul>
</body>