Bellows puffer style drywasher plans

[gcause]

Ok she's structurally complete now. She's a bit rough and ready but she will do

I got rid of the threaded bar as I want to be able to erect this and tear it down in the field so it all just goes together with nuts and bolts.

I added the top screen box. I am using 25mm x 25mm mesh as it was all I could get a hold of at the time.

I hinged the top screen box to the hopper box for easy clean out:

I can stand the screen up to get rid of any pesky rock that wont budge:

I secured the hopper with some washer headed screws to ensure it doesn't tear away under load.

With the screen up I have full access to the hopper (aka Laundry bag) to clear any blockages:

I went and purchased a windscreen wiper motor off gumtree so I just have to hook that up. Hoping I can do a direct drive system and not need the pulley:

Its getting there

 

[G0lddigg@]

Looking good mate

 

[Nightjar]

Gcause, Am using 6mm mesh, your 25mm mesh is far too big, rocks will rip that bag apart in no time.
Also you may need to make your drive a double roller, depending on the speed of the wiper motor you bought?

 

[gcause]

Thanks Nightjar,

I thought it was a bit too big but was all I could get at the time, I will go check out Bunnings and see what else they have.

Have to see if I can drill out the existing ball bearing joint on the wiper arm and put two rollers on like it like your setup.

Will also see if I can fit some kind of flow control to the hopper. i.e. tin with a sliding door on it that can be adjusted

Cheers,

Grant

 

[rc62burke]

Here you go, you should be able to get a fair idea about how this little 12V Dryblower works.

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower001.jpg

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower002.jpg

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower003.jpg

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower008.jpg

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower007.jpg

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower005.jpg

http://i151.photobucket.com/albums/s122/nightjar3/12VDryblower004.jpg

Hey Nightjar
Thanks for the pics.

Gave me the idea I have been looking for in regards the drive
cheers
Lee

 

[flashinthepan]

Hi , nitejar ,like the look of the simplicity with the 2 rollers on the wiper motor ,I'm assuming it just pushes the bellows up as rotates ,is there a spring on the bellows at all to pull the bellows down faster or does it just rely on gravity /weight to do the job
got to be the easiest /foolproof method i've seen yet ,and thats got to be a plus in the field
cheers , flash

 

[Nightjar]

A simple insertion rubber flap covers the air intake holes on the compression stroke then lifts for another gulp of air as gravity takes over and the bellows fall unaided.
From memory with the double rollers, pumps about 100/minute.

Cheers
Peter

 

[gcause]

Went over to Bunnings after work and picked up some Snake / Mouse mesh which they reckon is 6mm.

Will fit that to the screen instead.

 

[G0lddigg@]

Thats a better size mate I used that in my second mod only issue was it stretched and became a bowl after a while might save yourself some stress by supporting it accross the belly ina few sections

 

[Kawit]

You could probably just put it on top of the 25mm. That would give it a bit of strength.

 

[G0lddigg@]

Good call kawit

 

[gcause]

You could probably just put it on top of the 25mm. That would give it a bit of strength.

You read my mind

 

[Nightjar]

Have been looking around for some bearings/rollers to fit to windscreen motor that will be fitted to bellows dry blower summer project.
Always trying to save $$$'s walked into a Salvo's Op Shop and found just what I was looking for, $2.00.
Rollers from a skate board.
Hack sawed the skate board aluminium body from the axle.
Off cut of 25mm X 6mm flat bar.
Drilled holes and welded the two axles.
Drilled the end of the wiper motor shaft and tapped a 4mm thread.
Drilled and filed the centre hole to match the wiper.
Very happy with result.

 

[gcause]

Looks the business Nightjar. Nice workmanship by the way.

 

[MJB]

Excellent skills Nightjar

 

[aushunter]

Just a wee question,
You have a very fine weave mesh that sits under the riffles, ok, so what is stopping the super mega fine fines from being sucked back into the bellows. There would be some dust being pulled back in for sure. But I could be wrong.
Cheers
Brad...

 

[G0lddigg@]

hey Brad not that i run a bellows unit but the answer is yes you will catch a small amount of fine gold in your box?? is that a problem no because you catch the gold.... i clean my box out once every few sessions or when it get a bit dusty in there. i use a blower for mine too

 

[Nightjar]

hey Brad not that i run a bellows unit but the answer is yes you will catch a small amount of fine gold in your box?? is that a problem no because you catch the gold.... i clean my box out once every few sessions or when it get a bit dusty in there. i use a blower for mine too

Yes, agree with GD, we always vacuum clean out the box after a trip. Haven't dry blown for years (since the Minelab SD hit the scene) but am getting back into next season on a small scale.

This is slightly off topic but one trip we actually used an industrial type vacuum cleaner to clean out crevices in a wash. The vacuum was the type that is connected to a 20 litre drum. The outlet to the machine one side and the inlet on opposite.
Unfortunately this device was stolen and we never found another to replace it.

 

[Guest]

Night jar There's one on eBay for sale!

 

[outboard]

hey Brad not that i run a bellows unit but the answer is yes you will catch a small amount of fine gold in your box?? is that a problem no because you catch the gold.... i clean my box out once every few sessions or when it get a bit dusty in there. i use a blower for mine too

Yes, agree with GD, we always vacuum clean out the box after a trip. Haven't dry blown for years (since the Minelab SD hit the scene) but am getting back into next season on a small scale.

This is slightly off topic but one trip we actually used an industrial type vacuum cleaner to clean out crevices in a wash. The vacuum was the type that is connected to a 20 litre drum. The outlet to the machine one side and the inlet on opposite.
Unfortunately this device was stolen and we never found another to replace it.

you can knock one of these up yourself with out too much trouble, of course you run into problems using it because of the "hand tools only for collecting" laws for recreational prospecting, when I was wood turning in my 20's I used a 200 litre plastic drum and a standard industrial Electrolux vacuum cleaner with the hose entering through the centre of the lid and a 100mm pvc pipe coming in the side at an angle to get a vortex happening , very little dust got through to the vacuum cleaner unless the bin got full