Gentlemen, Just a little drywashing design help.

[Thurman]

HELLO ALL: I have briefly reseaerched this forum but still have questions. First, I am building a small (12V battery powered) puffer. The bellows will move about 8 in. and will be driven by a rotating cam instead of a U joint and linkages. (May have to revisit the usual approach after some experiments) Please consider that my interest in the design/construction is at least as important as the time spent drywashing, as I live in Florida. I am not necessarily interested in the lowest cost or effort; but new ideas, materials, crafrsmanship/appearance, simplicity, and mechanical/electrical efficiency are a high priority.

RIFFLES: The riffle tray is approx. 9 in. x 24in. I expect the adjustable tray angle wil be approx. 30 degrees to horizontal. I need advice on riffle height, dead zones, and angle to tray bottom material. The aluminum riffles will have a .062 x.062 void at the front bottom of the riffle for small stuff to call home.

SILKSCREENING: I have been looking at the aluminum frames used in silkscreen printing. High quality products. Not to mention the open material used on silkscreen frames - a wide variety exotic materials and "threads" per inch (how open). Has anyone tried these materials?

MOTORS: Motor recommendations: Looking around, it seems a puffer cycle should be approx. (1 puff per second); or 60 rpm. I know that motor rpm will depend, of course, on the load. Which makes me consider a motor with what they call pulse modulation to control rpm. Watching videos and talking with Keene Engineering makes me very partial to their small DW212V puffer and motor (the motor alone costs $250.00 with controller). I see tons of motors online for much, much less. I have seen that many use windshield and other geared motors (forget what they are called), (and have not counted them out), but I would like to buy the motor one time and have it work.

WHERE IS THE DOG: Several years ago I was on the verge of sending a check to Whippet Engineering to get on his list to buy his new drywasher! Regretably, other things got in the way. I mention this in admiration of his innovative approach to design and materials. Mine will not be that good. If someone has one for sale, let me know. Then I can forget this!

FINALLY: In the long run, I am sure that I should just buy the Keene drywasher. But that would not cure my itch for a great winter project with some innovations I am interested in. It could also be an exciting failure! Please be generous with your advice on any aspect of this post. Any thing will put me ahead of where I am. Science, experience, leads, philosophy (but politics are not allowed, and I am happy in that department) are all welcome!

Best retards to all, Thurman

 

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[russau]

Buying is the easiest and quickest path , BUT I liked making my own. Mine was a blower type (no explanation needed) the basic DW is kinda the same for almost all of these except for some points of improvement. If you make one for yourself OR buy one, make some extra parts for spares . a spare bellows ,hopper springs , a different punch plate with various sized holes for fine tuning it's operation. I used plastic to make my punch plate and drilled lots of holes in it and made a dead spot 1 inch deep and the width of my hopper tray and these holes were tapered from the bottom to gain more air pressure to help fluff the material. I covered this plastic with high count Muslin (old pillow or sheet )and I glued it to the topside of the plastic and made a spare while I was at it. Remember to build your riffle set aimed towards the material flow (just the opposite of stream sluice. I don't remember what height I made my riffle set but it was made from aluminum. I like spare parts because I used to travel all over to do my prospecting . Good Luck on your choice of procurement !

 

[bc5391]

HELLO ALL: I have briefly reseaerched this forum but still have questions. First, I am building a small (12V battery powered) puffer. The bellows will move about 8 in. and will be driven by a rotating cam instead of a U joint and linkages. (May have to revisit the usual approach after some experiments) Please consider that my interest in the design/construction is at least as important as the time spent drywashing, as I live in Florida. I am not necessarily interested in the lowest cost or effort; but new ideas, materials, crafrsmanship/appearance, simplicity, and mechanical/electrical efficiency are a high priority.

RIFFLES: The riffle tray is approx. 9 in. x 24in. I expect the adjustable tray angle wil be approx. 30 degrees to horizontal. I need advice on riffle height, dead zones, and angle to tray bottom material. The aluminum riffles will have a .062 x.062 void at the front bottom of the riffle for small stuff to call home.

SILKSCREENING: I have been looking at the aluminum frames used in silkscreen printing. High quality products. Not to mention the open material used on silkscreen frames - a wide variety exotic materials and "threads" per inch (how open). Has anyone tried these materials?

MOTORS: Motor recommendations: Looking around, it seems a puffer cycle should be approx. (1 puff per second); or 60 rpm. I know that motor rpm will depend, of course, on the load. Which makes me consider a motor with what they call pulse modulation to control rpm. Watching videos and talking with Keene Engineering makes me very partial to their small DW212V puffer and motor (the motor alone costs $250.00 with controller). I see tons of motors online for much, much less. I have seen that many use windshield and other geared motors (forget what they are called), (and have not counted them out), but I would like to buy the motor one time and have it work.

WHERE IS THE DOG: Several years ago I was on the verge of sending a check to Whippet Engineering to get on his list to buy his new drywasher! Regretably, other things got in the way. I mention this in admiration of his innovative approach to design and materials. Mine will not be that good. If someone has one for sale, let me know. Then I can forget this!

FINALLY: In the long run, I am sure that I should just buy the Keene drywasher. But that would not cure my itch for a great winter project with some innovations I am interested in. It could also be an exciting failure! Please be generous with your advice on any aspect of this post. Any thing will put me ahead of where I am. Science, experience, leads, philosophy (but politics are not allowed, and I am happy in that department) are all welcome!

Best retards to all, Thurman

Your motor RPM will be determined by the pulleys you use, most of the 12v puffers will use gear motors, the same as a wiper motor in a car, you can go to the local salvage yard and buy one, or shop at surplus center, here is an example of what you need, a smaller shaft would be better. Might be turning a bit more than you need, but it is controlled by the size of your pulleys..

175 RPM 12 Volt DC Gearmotor | DC Gearmotors | DC Gearmotors | Electric Motors | www.surpluscenter.com

175 RPM 12 Volt DC Gearmotor, DC Gearmotors, 12 VDC Electric Seat Motor New, right angle drive gearmotor originally made for use in electricF680N,

www.surpluscenter.com

 

[Thurman]

Buying is the easiest and quickest path , BUT I liked making my own. Mine was a blower type (no explanation needed) the basic DW is kinda the same for almost all of these except for some points of improvement. If you make one for yourself OR buy one, make some extra parts for spares . a spare bellows ,hopper springs , a different punch plate with various sized holes for fine tuning it's operation. I used plastic to make my punch plate and drilled lots of holes in it and made a dead spot 1 inch deep and the width of my hopper tray and these holes were tapered from the bottom to gain more air pressure to help fluff the material. I covered this plastic with high count Muslin (old pillow or sheet )and I glued it to the topside of the plastic and made a spare while I was at it. Remember to build your riffle set aimed towards the material flow (just the opposite of stream sluice. I don't remember what height I made my riffle set but it was made from aluminum. I like spare parts because I used to travel all over to do my prospecting . Good Luck on your choice of procurement !

Many thanks russau, very informative post. Good idea of supporting the punch plate supporting the Muslin, I have seen examples of this using very thin perforated metal. Making extra parts (while you are set up to make one) is great insight. Thank you for the inspiration!

russau​

 

[russau]

Your welcome !I'm glad you find it helpful !

 

[xracer550]

A good addition would be a motor controller you can change the speed without changing pulleys .
I just looked you can buy one like the ones I use on Amazon for $12 you just need to wire it = Also Look at the punch plate I use under the riffles it helps even out the pressure over the whole tray .

 

[Thurman]

A good addition would be a motor controller you can change the speed without changing pulleys .
I just looked you can buy one like the ones I use on Amazon for $12 you just need to wire it = Also Look at the punch plate I use under the riffles it helps even out the pressure over the whole tray . View attachment 2184437View attachment 2184441

Thanks so much for the input. I have bought a motor and a speed controller. Hope it works. The punch plate sounds like an excellent idea. Any information about where to buy the material would be appreciated. Along with, by the way, where can I buy perforated metal for the box I shovel into. The project is going good but all information is apprediated. Thanks for the thoughtful post.

 

[xracer550]

Try online metals they have many sizes shipped to your door . https://www.onlinemetals.com/en/buy/perforated-sheet