Backyard Aquaponics
A place to discuss aquaponics

This one looks pretty simple. Anyone tried this or something similar? https://www.youtube.com/watch?v=hxy3HLRmdiE

Hi Chris
for something like the multiple feeders you are planning I recon you would be better going for a feeder that
drops measured quantities.
Havent looked for a while but there where a few good simple designs on the net.

These timed dribble feeders are just not accurate although of course you can keep an eye on the quantities
as you refill them and get into the controller and adjust drop times. They where a PITA at the farm I worked on.
a bit of dust from the bottom of the bag and the rate went off or decided not to run at all . new bag of feed when they had changed the die or something at the feed plant and the rate changed - just frustrating

The ones that gave the least grief where a square nylon rod about 25mm (1") square and 100 mm long with a hole drilled in it
That was sliding in a piece of SS square tubing (very neat fit) Held horizontal above the tank.

At rest the hole in the plunger lined up with a hole in the top side of the Tubing with the feed bottle screwed into it

When triggered the plunger moved just slightly more than twice the hole diameter and dropped the feed through a hole in the bottom side of the tube. then returned to pick up another load. plungers came with different size holes to adjust the feed rates and the controller could be set for more than one cycle if needed.
The plunger was driven by a stepper motor and cam but those car door locks look good and seem to be pretty
reliable (in cars anyway)
They where a commercial unit from Germany but I don't remember the brand.

Hope this makes sense when I get a chance I'll see if I can find something similar on the net

Thanks John. I know that YouTube one doesn't look too easy to adjust. I also thought of being ably to change the feed rate using different sized holes, stoppers, and opening duration. I know it still won't be as good as a $300.00 commercial feeder, but I just don't have another 6K in my budget, and don't have the time to babysit my fish 8 times a day. Thanks for your input and explanation. I'll try and find that unit and see how it works. I also thought of buying 1 of the commercial ones and using their design to better my homemade one.

Hi CC
Also have a look at shotgun reloading equipment
they have auto pellet (and powder) measures that work on similar principles
might get some ideas there or a cheaper alternative

I'l agree with John, I don't think it'd be easy enough to control how much feed goes in, and it looks like it'd clog.

I'd go with the bore drill through a pipe connected to a drill. Turn the drill on for X amount of time at X speed, it forces the food through. And you can build the hopper to whatever size you want.

It may Colum. I think if the springs are heavy enough, it shouldn't. But still hard to regulate exact amounts. As I will need 15 of these, drill would be too costly. I did see an auger type, with a 3/4" auger bit in a metal sleeve that looked very accurate, but lots of fabricating and welding involved. I could do it, but it looks like an all day or even 2 day job. If that's the case, I'd be better off buying the $250.00 one. I can make the 12V plunger one for under $10.00, and it shouldn't take more then a few hours. But, you know the saying: Good is seldom cheap, and cheap is seldom good.

It doesn't have to be a drill. Plenty of cheaper options.

http://www.ebay.com.au/itm/12V-DC-3-5-R ... 53f08c9360

That'd work.

I don't think it'd take much to get it working, I could do it pretty quickly.

Duhh.wasn't thinking low voltage motors. That's would work. Would need a way too mount it and then make a hopper and small timer to activate motor. certainly has possibilities. Being a high torque motor, you would think it would not get clogged with the feed, and it would deliver appx the same amount each given time frame that it was running. thanks!

That looks like the way to go
I hadn't considered augers but with wood bits you can get good cheap augers
usually heaps in the second hand tool shops or auctions here

Easy to add a microswitch on the shaft to count revs or stop the motor
so you can use a simple timer

range of gearmotors here just for ideas - I'm sure you could get them out of ebay or china a lot cheaper
http://www.robotgear.com.au/Category.aspx/Category/60-12V-Metal-Gearmotors

And small flexible couplings are available like this
http://openbuildspartstore.com/5mm-x-6mm-flexible-coupling/

Thanks John, I was thinking along this line, but hopefully simplify a bit to make the build easier. I think I can go directly from motor to shaft using a coupling and grinding down bit shaft to fit.
http://youtu.be/I7_yUsjnHEY

Seems like you could use sheet metal and or plastic and get the same hopper without the extra hours of fabricating. Going to brain storm and see what I can come up with.

If you make the hoppers, you could make them a decent size too, so if your feeding a few kg a day, you won't need to fill up ultra quickly.

Take a template of the sheet metal into a metal place, and they'll cut it all up for you/bend it, then you just need to tack weld it all together.

Yeah, I was thinking the same thing. and making a clear window to see how much feed was left. I have a metal brake, so making the bends would be too hard. I just don't think you need to make it too heavy or thick. Could use plastic and glue as well. I think the metal would be cheaper. You could also drill and rivet the larger units together, or even self tapers. The small units would need to be pretty solid, or they would "leak" the fry powder out. Right now, I can't find the right motor/gear box/coupler combination to go from the small 5-6mm motor shafts to a 12mm(7/16" shaft for the auger bit.

I like the one that use Rob (its rob right¿?) (the user web4dev) in this forum, just an endless screw that trow the food:

https://www.youtube.com/watch?v=I7_yUsjnHEY

dvid. That's the same feeder we're talking about. It looks pretty simple and when combined with a timer, you should be able to adjust feed rate as needed. I just can't find that motor/gearbox combination and have not been able to locate a coupler for the small gear reduction motor that Colum located.