expoweb/handbook/rig/boltin.html

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<title>CUCC Expo Rigging Handbook: Placing bolts</title>
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<h2 id="tophead"> CUCC Expo Rigging Handbook</h2>
<h1>Bolt belays - Hand-drilling and placing spits</h1>
<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 (<a href="https://www.raumerclimbing.com/en/products/classic/tap-and-rainox/pack-of-10-tap/">Raumer Taps</a> / spits) or Hilti HKDS's.</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; 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.
<p>
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>Hand spits</h2>
<div class="onleft" style="clear: left"> <a
href="../../1623/161/l/boltin.htm"><img alt="(36k image)"
src="../../1623/161/t/boltin.jpg" width="113" height="152" /></a></br><span
class="caption">Bolting by Hand</br>(click to enlarge)</span> </div>
<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>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>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>
<h3>Peter and Phil's photo guide to placing a spit</h3>
<img src="hand_bolting_guide/img_2989.jpg" /><p>Decide where you want your bolt to go.</p>
<img src="hand_bolting_guide/img_2990.jpg" /><p>Before you start drilling, "dress" the rock; that is, hammer away the flaky top surface of the rock and flatten out a small area around where your spit is to go.</p>
<img src="hand_bolting_guide/img_2991.jpg" /><p>Hold the spit driver perpendicular to the rock and start hitting it, gently at first, while rotating it clockwise in between taps.</p>
<img src="hand_bolting_guide/img_2993.jpg" /><p>Make sure the driver is perpendicular to the rock surface.</p>
<img src="hand_bolting_guide/img_2995.jpg" /><p>After every few taps, blow the dust out of the hole.</p>
<img src="hand_bolting_guide/img_3001.jpg" /><p>It also helps to give the driver a tap to remove dust caked up on the end.</p>
<img src="hand_bolting_guide/img_3002.jpg" /><p>When the hole is as deep as the line around the driver shaft (about 3mm beyond the rim of the spit itself), the spit can be set. Take a cone, and fit it into the end of the driver,</p>
<img src="hand_bolting_guide/img_3003.jpg" /><p>like so.</p>
<img src="hand_bolting_guide/img_3005.jpg" /><p>Now hammer it in (without turning it, which would rapidly become impossible) until the spit is flush with the surface.</p>
<img src="hand_bolting_guide/img_3006.jpg" /><p>Finally, squirt a bit of grease into the spit to keep it from corroding. Notice that this spit is rather deep in, and would probably be rather hard to use for a rigging bolt; more dressing would be needed as well. This bolt was actually for the tag on cave 2005-07, and tag bolts clearly needn't be all that strong.</p>
<img src="hand_bolting_guide/img_3007.jpg" /><p>Finished spit.</p>
<hr />
See the <a href="drillbolts.html">Bolting </a> - Hang Fix anchoring<br />
See the <a href="/expofiles/documents/anchors/hangfixtraining.pdf">instructions and training</a>
- for expo bolting<br />
See the <a href="/expofiles/documents/anchors/anchor-appraisal-martingreen2020.pdf">2020 appraisal of anchors</a>
- comparison of alternatives <br />
See the <a href="rigit.html">Rigging and Bolting</a> - handbook
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