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Post by RKC on Nov 11, 2008 10:34:05 GMT 12
From: Roscoe Sent: 26/05/2007 8:32 p.m. Hi, Rob, I think we were intending to bolt the pump on the power jet and drive it from the surface. More hoses to wrestle with, linkingup. God bless Cam-locks.
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Post by RKC on Nov 11, 2008 10:34:45 GMT 12
From: Roscoe Sent: 26/05/2007 8:35 p.m. That might have been a `rover. It was on dark, and we were on our fourth stubbie after a hairy trip down the Big road, cutting blackberry and driving across the only 45 degree (sideways) bridge in Victoria. As the Big River Boys said 'Nobody comes that way'.
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Post by RKC on Nov 11, 2008 10:40:52 GMT 12
From: RKCNZ Sent: 28/05/2007 9:34 p.m. G'day dr_edger The Goldstriker in the photo you posted is nearly exactly the same as the one I had ... only mine had a different colored lay flat hose (orange) and it did not have the black (rubber?) attachment on the intake jets. It does bring back memory's ... but none good, unfortunately. I could immediately see that the Goldstriker in your photo has not done much work as there is no wear at the jet outlet ( at the spot pointed to in this photo img.photobucket.com/albums/v172/Coochee/GoldstrikerXXXwitharrow.jpg?t=1180330384 ). Herb got a lot of complaints from those customers of his that had done even a little dredging with their Goldstrikers who found a hole would appear in the soft aluminum wall after only limited use. And after this problem was pointed out to Herb, his solution was to attach a small plate of stainless steel at the wear point (which did fix the problem). And, I think, from then on the Goldstrikers he sold all had the plate attached (this could well have been when he stopped selling the Goldstrikers and started selling his copy of the Mighty-lite). However ... what this clearly illustrates to me is that Herb had not actually done much dredging with a Goldstriker before he started selling them, as, if he had, he would surely have been well aware of this problem and sold all Goldstrikers, from the very first sold, with the plate. I had a hole wear in mine at this wear point after only very little use. And, if I remember correctly, I easily fixed it myself by attaching a small plate of mild steel at the wear point, which was the obvious thing to do. However, simple problems like this should not be left to the customer to fix! At one stage when Herb was regularly getting customers complaining that their Goldstrikers were losing gold, he resorted to telling them that the expanded mesh that covered the riffles may have been installed in the wrong direction and all they had to do to get the gold recovery he claimed the Goldstriker got (over 95% gold recovery) was to take out the expanded mesh and reinstall it in the opposite direction (laughable now). No doubt that got a few dissatisfied customers out of his hair ... but it certainly would not have solved the "problem" (the 'problem' actually being that subsurface box's lose significant gold by the very nature of them being subsurface and nothing can ever be done to a subsurface box to give a guaranteed 95% gold recovery under all dredging conditions). The use of a Polypump was a extremely poor choice of pump, as to get sufficient suction the motor had to be run at max rpms. I once attempted to use my Goldstriker in a deep pool on a river near Braidwood (NSW) and I had to have the suction hose 'vertical' to reach the river bed gravel ... however at that depth (must have been only 10 or 15 feet) there was zero suction. So, it was a dredge only to be used at shallow depths ... and even at only shallow depths the motor had to be run flat out. A bigger motor and better pump could have been added to give sufficient suction ... but, obviously, then all the gold would have been blown out with the tailings, and it would no longer be a compact 'portable' dredge. Probably the biggest advance in dredging technology in the 80s is that its now possible to have good suction at the nozzle combined with excellent fine gold recovery in the sluice box (a good example is the Precision dredges) . A few days ago I came across an underwater video (on one of the recreational dredging forums) of a dredge operating underwater, and the suction on the nozzle was such that the diver could barely pick up any gravel and he had to just about thrust the nozzle into the gravel to pick up anything (it was painful to watch). Its a dream to work a Production dredge that has good suction as you have very little work to do (but you must be skilled and keep aware of what you are doing at all times) because the suction nozzle is doing it all for you and you can keep the nozzle away from the gravel, to more easily control whats fed into the suction hose rather than thrusting the nozzle into the gravel. I do however acknowledge that most hobby dredgers could not use a Production dredge as they would soon jam a finger or come to grief some other way. It takes training to use a Production dredge and those dredgers who read McCracken's books on dredging and think they then know enough to commence dredging professionally soon find there is more to learn about dredging. Regards, Rob (RKC)
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Post by RKC on Nov 11, 2008 11:16:32 GMT 12
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