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Mike Leahy's Diary

Day 12: Automated Panning

Five Months to Christmas
Mike contemplating his challengeI leave my hut to be greeted by another beautiful frosty morning. A Kia is squawking from the top of a tree silhouetted by the glowing mountaintops, illuminated by the still invisible sun. Kias are supposed to be rare, but we see and hear plenty of them.

As usual day three is a terrible rush. Looking down from the high bank it is soon evident that we have another problem to overcome. The river has changed height in the night, meaning we have to go through the whole tedious task of finding a half decent current again, so the first hour of the morning was pretty much a repeat of the previous afternoon. Bummer! When we do find a reasonable location for the waterwheel it is even further from the damn gold. We also have to stick the cradle high up on a large rounded boulder, which is hardly ideal. This leads to two problems: firstly the cradle is balanced very precariously and is difficult to rock, but secondly the pump that I have designed to lift water three feet or so above the river surface is unable to propel it up to the cradle. The pump is great at lifting, but once the water poured out of the top it is not under pressure, so can't be forced up a hose. Because the pump is more or less useless here we decide to bin it. This is a crying shame because the two tasks that really need automating - water pumping and digging - are going to have to be done manually. All that is automated now is the rocking motion of the cradle, not something we would have needed at all with the old design of sluice. This is hardly our fault though, because we had no idea where we were going to put the machine when we were building it. In a way it is inappropriate technology, much like some of the huge hydro-electric schemes in developing countries.

Automated systemAlthough the automated system isn't all we hoped that it would be, we really do think that it would be better at trapping gold, if only because it is better made and includes some new features – sacking and ribbed rubber mat. At first even the rocking motion is a bit disappointing. Some adjustments to the bolt, which attaches the driveshaft (broomstick) to the waterwheel, and placing some boards under the rockers of the cradle helps but we are still critically underpowered. Our only other option is to try to speed up the water current. By using plywood boards and boulders we manage to channel the water current a little, and by timing how long each rotation of the waterwheel takes we scientifically work out the best angles to place all our paraphernalia.

By mid-morning we still haven't started panning. This is terrible because ‘day' three always finishes at about 2 pm to allow the filming necessary to finish the programme. Our main concern is that we won't get more gold than on programme one. When we eventually do get everything going the full nature of our failure to make a workable system soon becomes evident because the work needed to keep our new baby monster fed with sand and water is pretty intensive. The gold bearing mud is a long way away so we opt to use large twenty five litre buckets. Digging the stuff out and carrying it along to the machine where J and Kathy are pouring the water and sand onto the cradle is seriously hard work and after an hour or so I am ready to stop.

Mike and Mike purifying tea tree oilLater, back at the sawmill Mikey is still struggling to purify tea tree oil. It's been very tight for all of us. The solvent test of our success, regardless of how hard the cradle was to ‘feed' is how much gold we have got. We set ourselves up for the final few pieces of filming. The filming goes well. We have got more gold, even with only an hour or two working the cradle at the river. It's a cool ending. I shouldn't have worried too much. Definitely a success.

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Photo: Mike Leahy
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