Many years back there was a small beach at Charleston, here on the West Coast. It contained quite a bit of micro fine beach gold. But there was quite a bit of small gravel to contend with. Black sanding requires only sand to be put over the tables, as small gravel impacts on the catching ability. So I decided that some sort of screen was required to remove the gravel.
Now I had this book on prospecting I bought many years back, it came from Australia. And in that book were the plans for a small scale vibrating prospecting table complete with a screen. It was built outa, what an Aussie would call scrap. And Aussie miners seem to have plenty of that hanging around going by the Discovery gold programs on the telly. Basically it comprised of a table and screen mounted on four old car leaf springs. A vehicle cam shaft was mounted on the back, that came into contact with the two rear spring leaves. The contraption was powered by a four HP motor, with a pulley, and a pulley belt going up to another pulley mounted on the camshaft. Seemed pretty simple to make I reckoned. Now I had a motor with a pulley. An ole vertical Briggs and Stratton. So it was off to the Car wreckers to get hold of the other bits. I already had a small beach table I had made, so hunted around for a mesh screen with the right size holes, and pretty soon had that.
Then it was out with the Arc welder and set to work. After a couple of days I had it together. Turned the camshaft pulley by hand a few times, and it certainly did what it was supposed to do. The back spring leaves went back and forwards a few millimeters, the screen and table shook and also the front spring leaves. It was beauty in motion to watch.
Right time to test it, so rang my mate Val(Valentine) yep it was also a boys name a few years back and arranged to meet him, at Constant Bay Charleston the next morning to test it. Val owns the Charleston Gold Mine (Stamper Battery for crushing oxidized inland black sand) so knows his stuff. Arrived the next morning as proud as punch with my home built vibrator. Val was impressed. “Ya done well mate, looks the bee"knee"s”. Now out the back of Vals place is the greatest load of old things, some would call scrap. But to Val it was treasure. So he knows his stuff. And off to the beach we went.
Set it up by a small creek at the southern end of the beach. I had another small pump for the water supply, but we decided to do the test with out that hooked up. Right last minute check, full tank of fuel, choke on. All good to go. The ole Briggs was a temperamental ole bitch, so knew it would take a few pulls to get her cranking. It was quite hard to pull, as the cam was in contact with the spring leaves, Mmmmm I said to Val really needs some sort of clutch, but I can sort that later. After a few pulls the motor fired up
, With its usual smoke being a two stroke motor. Throttle was only on idle, and as it had to much work to do, promptly stalled. Easy fix I said to Val, I will turn the throttle right up, which I did. Then gave her another pull. Away she went at full throttle. Clack clack clack went the cam and behold she vibrated, back and forward went the spring leaves, table and screen, so fast the eye could hardly see this wonderous phenomenon taking place. It works, it works I cried, its doing just what it was designed to do. Damm those Aussies are pretty smart. I remarked. Okay it was pretty loud with all that clacking, but I could live with that. Hardly a stealth machine if on unclaimed ground, but PAM is a damm long way off, so no probs there.
Well things went well for about a minute. There is always a few problems when trying out a new procedure. Things started to smoke a little bit, seemed to be coming from the cams. Guess next time we had better bring a grease gun, And grease the cams I remarked to Val. That will cure that. I"ll run it for another minute or two and see if if it settles down. Well that didn’t work, the smoke got thicker, and the cams started to turn a cherry red. Guess we better turn the motor off Val, you do it he said. You built it. Now like I said this was an old motor, and the kill switch was a strip of metal with a rubber coating on one end that sat above the spark plug. By pushing it down you shorted out the spark plug. So I was gunna have to reach right under the table to achieve this. Safety gear was unheard of in those days. Slowly I ventured towards it, by this time small bits of red hot cam shaft were flying off in all directions. Frig this is gunna be tricky I thought. As if it was reading my thoughts, the motor that was laboring under this unplanned outcome, suddenly sped up and now it was really delivering the rpm"s. Must have been the cams reducing in size as bits flew off. By now the table was vibrating so much it started jumping up and down. Frig I said to Val, it’s alive, look at it go. By now there were billows of smoke and flames appearing. Up it jumped higher and higher, and not content with that it started to creep along the beach, slowly at first, then gathering speed as it gained momentum and it’s new found freedom. By this time stopping the motor was outa question. My wonderous machine had now become a monster, breathing smoke and flames. Down the beach it hopped like some prehistoric fire breathing dragon. Clacking as it went. Jeez Val I yelled, we are going to have to kill it. "Not we says Val you created it, you kill it.
To add fuel to the fire (not that it needed anymore) down the end of the small beach was a young lady sun bathing and the dragon was heading in her direction. Thoughts ran through my head, with the local newspaper “Headline” Reading. “Sun bathing women at Constant Bay attacked by out of control vibrator” . Grabbing a long driftwood pole I set of in pursuit of the beast. There was nothing for it, I had to be Sir George “The Dragon Slayer” and topple this beast before it attacked. Evil thing that it is. As I got closer, it must have sensed my presence, and in a series of hops turned around, and started coming at me breathing its fire and smoke. Now the tables were turned and I had become the hunted, so off I took, with the beast in hot pursuit. Val was ahead of me, sitting on a sand dune watching all this unfold. As I neared I yelled to Val to grab a pole and as I pass rush out and take the beast by surprise as it was focused on me. Val fell to his knee’s hands clasped and glanced towards the heavens. Great help he is being I thought, divine intervention ain"t gunna help me here. But then Val climbed to his feet and grabbed a nearby length of driftwood. I don’t know about his prayers, but mine were certainly answered. Val was coming to my rescue. Hit it fair in the guts I cried, go for a mortal shot. Luckily for Val there was an onshore wind and with the smoke cloud blowing his way, he had a smoke screen to get in close without the beast seeing him before he drove his spear home. Val appeared outa the smoke at full trot, lance held forward like a true knight. Hitting it fair in the guts, Well done Sire I yelled, it’s done for now. The beast toppled over and lay on its side. But it wasn’t done for yet. The motor roared and the beast began to go in circles on the sand, die ya bastard die I cried. Never having killed a dragon before this was all new to me. By now it was engulfed in flames, but still alive. Frig I said to Val, take cover, it’s got a full tank of gas, its gunna blow. Quickly we ran and hid behind a nearby sand dune as the beast entered it’s final death throes and finally it was done. With a tremendous explosion it disintegrated steel flying in all directions, Much like a german 88 millimeter direct hit.
Well I said to Val, Ya just can’t trust those Australians can ya. Maybe I can modify the Mark Two version. Like hell you will remarked Val. Lets make a trommel revolving screen instead. Far safer.
Cheers Trev aka “The Hatter”