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How to move your spoil

By Stu Lindsay

The bags

Usually plastic, they come from a number of sources and the quality varies a lot. Good old fashioned fertilizer or animal feed bags are amongst the strongest but not always the easiest to empty. Yes, some bags do need to be emptied as cave digs do not always have masses of free space where they can be stored and, more importantly, hidden. Hand in hand with the plastic bag often goes the strop, a mini 60cms loop sling; this gives an easy grip for dragging, pulling about or hauling up pitches. It hooks straight on and most importantly it keeps the spoil contained. Used in conjunction with a drag tray they can make spoil removal much easier. In the past few years the plastic “hessian weave” type bag has become available as the more we drink the more the brewery’s use! They are easier to empty being less rigid and do not tend to grip muddy spoil with a near perfect vacuum-like resistance, as do fertilizer bags. They are also relatively safe moving boulders; we have done rocks to 40kgs in a well stropped bag…and one of over 50kgs in a double bag!

The drag tray

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There is a vast array of “models” in this category and they are mostly modified plastic drums of 25 to 40 litre capacity. The drag tray is a simple thing; you can get 2 from each drum. You cut it in half from top to bottom; each drum can yield slightly different trays if you cut it off centre. Using the handle as a guide you cut it so that the whole handle stays on one section; this gives a deeper tray and something to grab hold of if you need it to be tipped. The thinner section is great if you are merely using it to drag bags between points that are reasonably flat and in a straight passage, or up slopes. The most important thing with a drag tray is not to fall into the trap of “great, a nice convenient handle to tie the rope to” and then suffer with awkward moments if the tray is unstable or travels badly. Why should you avoid tying to the handle? Because you will find the pull is often above the centre of gravity. In all trays I have made the drag rope attachment points are as low as possible, wide apart and the leading/ pulling end always rein forced, using a sturdy thick rope with a thinner one on the return side if you

wish.

The kibble (bucket, skip)

BB548 003Again there are loads of models; the primary source is the 25—40 litre plastic drum. Preference and construction is usually down to the hands of the maker and the conditions in the dig. Most kibbles will operate in most digs, but for that awkward or odd point in the digging chain you can usually make something to suit.

Example 1: In Cainehill we have a rift 8m deep which is narrow and stuff needs to be got up it. Rocks in a bag would last no time at all so a simple solution was to cut the handle section from the top of a drum, attach an old bit of seat belt around it, reinforce the plastic one side and the webbing on the other with washers and use rivets to hold it in place down the sides and on the bottom. A maillon or old krab then joins 2 end loops together at the top and a sturdy flexible rock hauling vessel that is easily tippable in a cramped space is the result.

Example 2: Cut the bottom from a 25 litre drum then using 1” wide tape wrap around the handle twice, keeping the tape centrally placed, 2 equal lengths then go up the side, melt 2 slits (stronger than cutting) in each side above halfway and feed tape in and out, tie loops on the ends to affix a permanent maillon and you have a flexible kibble with a handle on the bottom for easier tipping. As in all instances a piece of chain tied to the handle also helps in muddy conditions.

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Example 3 & 4: A 25 litre drum holds probably more than 25kgs of solid stuff; that would be especially true if it was mud, and more so very wet mud. The metal framed kibble is useful in a variety of aspects; the frame of the kibble can be used as an integral lifting and tipping part. The metal frame is constructed around the top of the cut off drum using fairly wide metal, 20mm then 1 or 2 bands are affixed to this going down around the bottom then back up, these can be narrower metal, 10mm. The handle is fixed to the wider rim, it can be central or offset by an inch or so; offsets can make for easier tipping by hand or from a fixed rig. The handle framework also means there is a firm point for attaching to guide wires etc.

Notes

These metal framed kibble type buckets do not like to be bashed on the top edge, especially when moving claggy clay as the clay takes the shape of the bucket, the bucket is bashed more and more to get it to come out, the shape of the top changes with more banging, the clay is rather stubborn, preferring to stay as a squarer lump in the bottom and refusing to pass the modified exit.

True of most kibbles, when digging claggy clay a half sized kibble avoids overfilling, reduces weight and provides fewer surfaces to stick to. For rocky, dryish spoil or gravel use a three quarter drum. Handles to attach can be made from solid metal, rope, tape or chain. Always cut off the bottom as the top becomes a ready made handle on the bottom for tipping!

The rock kibble (varying sizes)

Used in Assynt and manufactured by those famous SUSS engineers (F & B) is the rock kibble, cut from the bottom of a round barrel, 40 – 200 litres depending on your fancy. It has four sturdy attachment points for chains. These are basically 2 flat metal bars (2” wide) which go at 90 degrees to each other under the bowl and are bolted into place; the chains come together at a maillon for a permanent attachment point, and are long enough to get a rock in and out when spread. They should easily be able to handle 60+kg rocks hauled to the surface up a pitch! The rocks are merely rolled in and rolled out! 80kg can be no problem.

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The enclosed kibble or cut away kibble

BB548 008An awkward looking bit of kit, this is usually attached by the existing handle. These are useful if there is a pull along a bit of flat passage with a section of vertical lifting ; depending on the spoil type they can prove difficult to tip as the cut out hole tends to govern the mass of the contents. The less viscous the spoil (slurry!) then the bigger the volume can be. If A is a 1/3rd of the kibbles depth the hole to extract or tip the contents from the loaded end by way of tipping and shaking is by virtue of the open diagonal, d to e, allowing just more than a 1/3rd of the volume to be tipped easiest. The load, clay or similar, in the bottom section below B should therefore be no more than 1/3rd of the kibble volume. A mistake often made is to fill them to the top, line A, with fairly thick claggy spoil that binds together, shaking causing it to lump up even more, so its true, little but often works best. Wet slurry type spoil, when being pulled flat can be filled to the point of over flowing, as when raised it should be below line A.

To make one simply catch hold of the handle, cut away the top corners/edge of one side, attach a strop or something similar to aid attaching to a krab or maillon, add a rope or bit of chain to the bottom and hey presto a few seconds later and you have a kibble. The main disadvantage is by using the handle for lifting there is a higher centre of gravity when dragging, resulting in stability being a negative point, but usually containers are “oblong” with the handle favouring the cut.

In the late 1970’s a converted beer barrel was commissioned to extract spoil at 50kg a time from Wigmore Swallet. Like all good plans it had to evolve. The second part of the plan was hatched as we went along on that first day; an aerial ropeway with 2 perfectly placed trees and masses of space for spoil. It just had to be! The concept was simple, as was the offsetting of the centre of gravity horizontally and vertically of the barrel and the krab release so it would tip itself. The barrel part worked excellently but getting it to the tipping point was a completely different story…another day perhaps.

Operation was simplicity itself a krab on the handle slipped over a fixed pillar on one side of the barrel. When lifted the barrel tipped upside down; the hardest part on the tip operator’s part was swinging the empty barrel back up and putting the krab back in place.
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It is not all about the receptacle in removing your spoil and performing a relatively simple lift up a vertical shaft. Inclined areas coupled with rough floors in a relatively cramped passage or crossing a void often needs a bit of thought. With the Tyrolean or zip wire in the armoury we can see that pretty much all aspects of spoil removal in most situations can be sorted using vessels, pulleys, (ropes) wires, poles, guides, maillons, krabs and anchors. Always start with KISS and if it doesn’t work then build up on it.

Providing there is something solid to attach to at both ends using a zip wire (preferred) or rope can be a godsend. The best operation is of course with a down hill slant, but providing the passage is straight a rope on either end of the vessel will work. Materials needed are a couple of anchor bolts, the spoil vessel, old rope for pulling to and fro and a maillon or krab or two. For a simple short term operation an old maillon sliding on the wire should suffice. For longer term use or maybe heavier loads a bogey as in Diagram 7 would be beneficial.

However, from the outset simple might be how you build a 3 wheel rig. It is basically 2 modified triangles of metal to form cheeks, 2 pulley wheels affixed to top 2 corners, a third lower and centrally positioned and 3 hanging points on the “sharper” end with spacers in the middle for rigidity and /or draw ropes or load points as necessary. The above system can go up/down quite steep slopes, across voids indeed anywhere where the vessel is mostly clear of the floor. Diagram 7 shows the bogey used in Locke’s Hole where the entrance shaft is near vertical but has many protrusions, especially the steps! I managed to get a guide that worked perfectly on the 3rd attempt. First task in setting up is to
get a piece of string attached to the centre of a head frame/ top anchor point then find a suitable line to a robust sturdy lower anchor point.

BB548 012Locke’s problem was that a mere guide did not suit as the weight of the load needed to be “suspended” on the wire, and opposing forces (pull, hang and sideways motion) seemed to negate the effort and readily wore through steel krabs/maillons, My offering for lifts greater than about 20 degrees from vertical must be the three wheeled bogey / pulley with attaching points to allow for 25+ kgs going up, and a free running zero load, or controlled 40+ kgs down. It works and I offer no technical info on how or why it does such a good job, whereas its immediate similar predecessors didn’t; it’s like most digging i.e. “suck it and see”.

In construction there must be adequate solid points to keep the plates apart and allow the wheels to revolve. In diagram 7 (the top plate is removed for clarity) there are 3 fixed points, good for attaching krabs and it is set up for pulling up a 20+ degree incline, if used more horizontally then the load could be put on the spare rigid fixing point.

In a vertical scenario, maybe a shaft with a reasonable dog leg and protrusion, a zip wire or guide wire may be needed to guide rather than support a vessel which should always hang vertically. The simplest guide is a krab/maillon between kibble and wire/ rope, great if minimum load is put directly on to it, but metal against metal (or rope) doesn’t last long. A guide wire will probably work without too much friction up to about 10 degrees.

Rigid rails

These can be in exceptional cases mono but are mostly double, and fixed to the floor, possibly turning gentle corners and able to tackle inclines and varying distances. If a long term project over a long hauling distance is planned then the time and labour may be well spent. We all know how a railway line works so that covers floor mounted aspects of rigid rail, so how about suspended ones:-

The short rail, attached at both ends above ground with its length dependant on the amount of sag that can be tolerated, has a block, usually like the triangular offering in diagram 7 but with a much larger wheel(s) ( 7-10 cms dia. and maybe 3-5 cms wide) with the end to end movement probably no more than 9-10 metres, supporting about 25 - 40 kgs.

In construction there are a couple of options; the block may have 1 or 2 running wheels, the equilibrium being based on the hanging load keeping the block up straight. Attaching a kibble or bag to the load point and walking it to the other end along a rail of 2” scaffold or similar pole is the simplest way as it allows for moving larger weights. Whilst 20kgs is fairly comfortable for most diggers to lug around, this rail could allow for loads of 35-40kg. If incorporated with a simple human influenced lift from the dig haul line onto the mono rail, and a method of semi automatically tipping at the other end, you get more load for less energy.

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This idea derives from the system in use in Assynt (see photos)

The 2 highlighted areas show a pulley with single wheel, and the end stop which the kibble hits and is displaced from the transporting hook under the pulley wheel by the impact so that through the wonders of science it lands upside down in the wheel barrow. A handle on the bottom is used to pick up the kibble which has usually disposed of its contents. The rig shown, with 7 people on site and about 5 hours working, raised 280 kibbles, each weighing close to 30 kgs…that’s over 1500 kgs an hour.

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Above Close up of pulley and tipping bar

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The author in action in Assynt
The BEC has been blessed with the rat haus a gift from Matt Clarke; what Jrat always wanted! It has a really sturdy bench, a massive vice, a grinding wheel, and will welcome any useable old tools! You can make your own stuff, so then there is no reason not to have the tools to go digging. How’s the song go…Oh yes, “We are the Exploration Club we………………………”