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<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>
you are using hand bolts (spits) or drilling using Hang Fix anchors.</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.
<p>
Different types of hanger have different footprints. 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>
<h2>Power-drills and Hilti anchors</h2>
<h3>Hang Fix anchors</h3>
<p><a href="../../documents/hangfixtraining.pdf">Hang Fix training</a>
<p><a href="trainingrecord.html">List of people trained for installing hang fix anchors</a></p>
<p>See the <a href="../../documents/anchor-appraisal-martingreen2020.pdf">2020 appraisal of anchors</a> and choice of bolt types for future expos.
<div class="onleft"><a href="../l/bosch.html"><img
alt="(73k image)" src="../t/bosch.jpg" width="250" /></a></br><span
class="caption">Using the Drill</br>(click to enlarge)</span></div>
<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>
<h3>Spits</h3>/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
alt="before setting - 1k png" width="530" height="90" style="margin: 10pt"
src="../../years/1990/hilti1-100.png" /></a><br />
<b>Hilti HDK spits before and after setting.</b><br />
<a href="../../years/1990/hilti2-300.png"><img alt="after setting - 1k png"
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 />
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<p>Anchor placement and dressing the rock is achieved in the same way as for Hang Fix anchors. A spit should be threaded on to the driver, placed on the rock and hammered. Rotate the driver clockwise, as you hammer. This will move the teeth around and ensure that the spit is firmly threaded on to the driver. If the spit becomes unthreaded as in hit the threads will be ruined. Keep drilling until the surface lines up with the line on the driver. Then pop a cone in the end of the spit and hammer it into the hole.</p></body>
</html>