New Zealand Gold Prospecting & Metal Detecting Forums Archive

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1864hatter		Posted : Friday, 26 October 2012 2:27:22 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)		Hey guys have any of you ever used a battery powered air compressor for shallow diving purposes? Im pretty keen to get one of these http://www.youtube.com/watch?v=x8f_87UaXtE
		And now....On sandy beaches and muddy soil, rings and coins await my coil!

NUGGY		Posted : Friday, 26 October 2012 10:01:07 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 20/07/2012(UTC) Posts: 267 Location: greymouth Thanks: 85 times Was thanked: 76 time(s) in 58 post(s)		Sweet machine! I could be keen too. my sound isn't working - so I could not hear what they are called? I guess it depends on how big a battery you need to carry around to work it too as to whether or not it would be good for what I had in mind. Thanks Nuggy

oroplata		Posted : Saturday, 27 October 2012 12:47:46 AM(UTC)
Rank: Gold Ingot Groups: Registered, Moderators Joined: 16/06/2011(UTC) Posts: 1,040 Location: Christchurch Thanks: 23 times Was thanked: 211 time(s) in 152 post(s)		You got it Nuggy - the battery weight is the problem. If you compare the energy available in a battery compared to the same weight in gasoline - gasoline wins hands-down. Take a gokart with a 12volt motor and a car battery - how far would you get on that compared to a petrol motor gokart with the car battery's weight in gasoline? No where near as far. Then try it with the equivalent weight of alkaline batteries wired up to provide 12v and you'd get even less mileage (aaa batteries are pretty much the most expensive form of energy for sale - the price/kw is off the scale compare to gasoline. So say you lug a car battery into the bush along with a electric pump. At the end of the day (or once the battery's flat!) you have to lug the battery back out and it still weighs the same amount. If you took a SMALL gasoline powered by and a car battery's weight worth of gasoline in a tin into the bush, you'd get many more hours of compressed air AND you'd be lugging an EMPTY gas tin out at the end of the day when you're dog-tired! And we're talking a pretty small gas engine too - you could probably build one out of those little engines on a petrol lawn trimmer.
		WWW

x-terra steve		Posted : Saturday, 27 October 2012 9:32:43 AM(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 again Hatter, have not seen that set up in action, 12v @ 120 whatts is about 10amp i think, Like the idear of next to no noise and no nasty fumes to deal with, you could invest in a couple of batterys and recharge them back at camp via your car, Was talking about up the waka were D C enters, cheers

NUGGY		Posted : Saturday, 27 October 2012 10:30:47 AM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 20/07/2012(UTC) Posts: 267 Location: greymouth Thanks: 85 times Was thanked: 76 time(s) in 58 post(s)		I still own a couple of Tomas compressors from the 5" dredge I had, and I also have a 3.5 hp Honda motor that I was going to run one off. This is going to weigh somewhere around 20 kilos with fuel in it, which is not too bad, but lighter would be better.

element111		Posted : Saturday, 27 October 2012 10:27:54 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/12/2011(UTC) Posts: 114 Location: blenheim Thanks: 49 times Was thanked: 34 time(s) in 21 post(s)		hay hatter we got a spare t80 compressor at home we not using just mount that to a small 1hp or what ever motor and make a frame on a back pack to carry it to snip where ever you want? thats just an idea if the electric one is a bit of a mish

x-terra steve		Posted : Sunday, 28 October 2012 11:05:06 AM(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)		Nice one element111, Have the same set up using a 2.3hp petrol motor, have tried a smaller motor of 1.5hp but had to rev its guts out to get it to work and then it would die. T80 runs sweet around 1800 rpm they dont like to be over reved, using a 90mm dia pulley on the motor and 150mm wheel on the compressor, If any one out there is setting a unit up can give all the details and ave a digital tachometer you can borrow. Bugger the rain Steve

Metal Mikey		Posted : Sunday, 28 October 2012 11:35:04 AM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 29/03/2012(UTC) Posts: 120 Location: Rangiora Thanks: 17 times Was thanked: 22 time(s) in 18 post(s)		If you want a battery in the bush you can charge it with a solar panel and some sort of regulator. Cheers Mike.

element111		Posted : Sunday, 28 October 2012 1:05:56 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 2/12/2011(UTC) Posts: 114 Location: blenheim Thanks: 49 times Was thanked: 34 time(s) in 21 post(s)		hay that sounds allgood steve,yea we spent all day morning till dark in the river yesterday in the rain hit a nice spot so didnt want to leave,doing it all again tomorrow lol

pc5001		Posted : Tuesday, 6 November 2012 7:48:41 PM(UTC)
Rank: Gold Flake Groups: Registered Joined: 5/08/2011(UTC) Posts: 26 Location: central otago nz Was thanked: 13 time(s) in 8 post(s)		[img]null[/img][img]null[/img]Hi all,thought you guys on this thread maybe interested in a little project Ive had in the shed the last couple of weeks...engine is a 2.5 hp and its mated to a Speedy compressor. These compressors were built by W.R.Brown of Chicago ,originally made for spray painting they were made through the 50s,60s and 70s and were popular with american dredgers as a source of clean ,oilfree air.this one I have ,despite being 40 odd years old ,is in remarkably good shape. For those of you familiar with Hammys book, this is like the compressor used by Ray Woodbury as he dived for gold at the junction of the moonlight and the shotover....cheers Edited by user Tuesday, 6 November 2012 8:47:10 PM(UTC) \| Reason: Not specified File Attachment(s): DSC_0035.JPG