Adding air

Sick4gold

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Jun 11, 2013
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Indiana/Ohio
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I have a 3 inch keene dredge, I was thinking about adding air but have a few questions.
Right now my dredge runs pretty even side to side, I've been looking at air setups but wouldn't they weigh down 1 side of the dredge and make it lean?
How do people add air to 2 1/2 inch, 3 and 4 inch dredges after the fact or should they be ordered with air to keep the well balanced?

Also I've been looking at air systems and OMG are they expensive with regulators and masks and everything. Where is everyone getting their setups and what's the average cost for a cheapie setup?
 

The t80 from Keene will get one diver to 10 feet and its not heavy enough (maybe 2-4 lbs) to unbalance dredge. After market add-ons, idk. If your back is screaming at you from long-arming all day, its worth the money. Is your river/creek clear enough and deep enough to work
underwater?
 

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You can cut cost by buying PVC air hose don't pay keenes prices. My backup Reg. is a scuba 2nd stage you have to pull air a little harder but they work and are cheap on eBay. You can use any mask you like.
 

Adaptor plate can be moved a inch or so to compensate for the miniscule weight difference. MAJOR importance is the belt adaptor changing the distance between the hose bib on the suction end of the pump. The impeller MUST be up against or as close as humanly possible to the plastic bib to metal impeller to prevent blowby as then your pressure drops bigtime. Conversely opposite too far out and it hits up against-seen'm push it out and engine is frozen in place. John
 

Thank you, never thought of moving the engine opposite a little.
I'm not really worried about unbalancing the dredge as it seems pretty darn stable but more of pitching my sluice box to one side and having to compensate with a rock which vibrates all over.
I'd just love for it to vibrate off and come sinking down into my head. Probably not kill me but a 2-4 lb rock love tap doesn't sound like a great day.
Does anyone have a rough est. as far as total cost? 10 ft is plenty
 

Adding air will take a little work on your part. You will need to add a pulley on to the motor shaft which means you have to completely disassemble to pump to remove. The motor will need to be mounted onto a plate so that you can mount and adjust the air pump to be tight on the belt. If you can get a good look at a Keene setup, it's easier to understand than trying to explain. Keep in mind that a T-80 will rob about 1 horsepower from the output, so if you are marginal right now you could be under-powered after.
 

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Full video on golddredger.com,rebuild t-80 also. Nuttn' but a Thomas oil less paint compressor available from paint suppliers and contractors supplies for about 1/2 of mining shops. Try craigslist. Don't forget reserve tank for heat disapation and water condensation also safety too. 2nd stage regulators all over the net,just have to reduce tension on spring for lower pressures on t-80 vs tanks-John
 

Nuttn' but a Thomas oil less paint compressor available from paint suppliers and contractors supplies for about 1/2 of mining shops.

HJ, please list a link to one of these companies. I have been searching for one but NOTHING close to a t-80. Most of them are 110V, and none I have been able to find are adaptable for use as hookah.
 

i bought my Brownie compressor for $30. and took it apart to make sure it was ok! Johns referal to these oiless compressors is correct. Sears sells them with their compressors. try a goggle search for "oiless air compressor"look at yard/estate sales for old compressors that dont work anymore.theyve been out there for years and are cheap.just take them apart and check them out BEFORE using them!as far as the direct drive units, im sure a person could figure out how to put a pully on it if he really wanted to. i did,so anybody could!
 

A dive shop can "rebuild" your regulator for low pressure use. I think my last one was done for $35.00 from a local dive shop
 

Please consider an air filter. We used them while under water for 6 to 8 hours at a time (20 foot shallow)
in the florida keys. Oil & fumes from the exhast are the problem. At the VERY least, keep your air intake
as far away from the engine exhast as possible. If you decide to build a filter, here's a start.

4 inch x 20 inch pvc pipe.
clean sand
activated char coal
nylon stocking
end caps & fittings
 

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