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gold dredge problem - unsure

wright tanks dredger		Posted : Monday, 5 August 2013 8:41:35 PM(UTC)
Rank: Gold Dust Groups: Registered Joined: 5/08/2013(UTC) Posts: 0 Location: timaru Thanks: 5 times		hay guys iv just brought a gold dredge which has been home made. im very inexperienced in gold dredging and was unsure at what to look for when buying. 1 problem i think i have is with what i think is called the power jet where the water is pushed into this tube by a 2 inch hose. and the barrel it self is 4 inces wide and the hose where all the gravel is sucked through is 2 and a half inches??? does this sound like its been made right or could some one show me the specs on how to make this part for my gold dredge File Attachment(s): steven 099.JPG steven 094.JPG steven 093.JPG steven 098.JPG
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1864hatter		Posted : Monday, 5 August 2013 8:54:56 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 4/08/2010(UTC) Posts: 1,007 Location: Auckland.... Thanks: 49 times Was thanked: 566 time(s) in 269 post(s)		Normally the power jet is the same size as the suction hose itself. You could sort that out by jetting a 4 inch main hose. I'm not sure how the suction would be affected with your current setup. The 2 inch jet going into a 4 inch power jet seems ok tho.
		And now....On sandy beaches and muddy soil, rings and coins await my coil!

simon		Posted : Monday, 5 August 2013 8:55:23 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 7/01/2011(UTC) Posts: 789 Location: Central Otago Thanks: 33 times Was thanked: 239 time(s) in 150 post(s)		Maybe post a pic or two mate. that should give us an idea of what we are talking about. at the moment my first question would be has this home made dredge actually recovered gold? i don't want to alarm you but i have seen many for sale that have never been tested, some are hardly completed even. so a pic should show us what we are looking at. what exactly was going wrong? did you get the engine going? was it sucking water thru it? if so did it pull the gravels thru ok?
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Golddigger7		Posted : Tuesday, 6 August 2013 10:08:07 AM(UTC)
Rank: Gold Ingot Medals: Groups: Registered Joined: 6/09/2012(UTC) Posts: 252 Thanks: 1 times Was thanked: 46 time(s) in 35 post(s)		Hey WTD Im guessing from your discription is that you have a 2 inch power jet joining the 4 inch pipe, which i would call the lifter unit or log. Then what you have is a 2.5 inch hose connected to your lifter unit. This has probably been done for two reasons 1) it possibly improves the suction, and 2) it reduces blockages and or 3) the people you bought irt from where to cheap to buy a 4" suction hose. Post a picture of the dredge as stated above, and we can then check out the setup and whether the motor and pump are the right type to drive a 4' dredge. If they are ok you should be able to fit a 4 " suction hose and have some happy sucking.

simon		Posted : Tuesday, 6 August 2013 1:51:26 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 7/01/2011(UTC) Posts: 789 Location: Central Otago Thanks: 33 times Was thanked: 239 time(s) in 150 post(s)		pics? what type of ground were the old owners dredging? i think maybe they were after extra suction power to hit somewhere deepish. if you are only ever dredging shallow holes you should be fine with a 4 inch hose. i reckon less stuff would get stuck with a 4inch. as long as you have some sort of reduction on the nozzle end this should stop most blockages. how big is the engine? if suction is no longer any good with 4 inch hose perhaps it would be a good upgrade to fund with some of the gold you recover. a bit more gas consumption but could be worth it.
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x-terra steve		Posted : Tuesday, 6 August 2013 8:14:29 PM(UTC)
Rank: Gold Ingot Medals: Groups: Registered Joined: 7/04/2010(UTC) Posts: 224 Location: Nelson NZ Thanks: 103 times Was thanked: 69 time(s) in 42 post(s)		Hi there WTD, made a few home made units, a photo would be a big help to sort out the problem, Motor HP, lift or psi of the pump output is a biggie, lift X 1.4 = psi, power jet size where it enters the log is also very important, its all about balance PSI,Liters PM, Steve

wright tanks dredger		Posted : Tuesday, 6 August 2013 10:22:47 PM(UTC)
Rank: Gold Dust Groups: Registered Joined: 5/08/2013(UTC) Posts: 0 Location: timaru Thanks: 5 times		hey guys i didnt get off work till late im ganna set it up tomorrow and ill get the pics on tomorrow night thanks
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Golddigger7		Posted : Saturday, 10 August 2013 2:53:33 PM(UTC)
Rank: Gold Ingot Medals: Groups: Registered Joined: 6/09/2012(UTC) Posts: 252 Thanks: 1 times Was thanked: 46 time(s) in 35 post(s)		what a machine, good to get your first ounce or two, and then start upgrading bits a pieces

jafa		Posted : Saturday, 10 August 2013 3:43:27 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 22/11/2011(UTC) Posts: 134 Location: auckland Thanks: 22 times Was thanked: 23 time(s) in 19 post(s)		looks good about the only probablum you could encounter would be rocks jaming on the bit you slide your hose onto and possibly the angle of the jetlog if there isnt much suction id look at putting less angle on it it should be about 11 degrees but there both maybe,s it could work fine.
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