External Pump from Old Motors

[seth]

Hi all,

It's been a while since I last posted here. (Admin, could you reset the p/w on my account, please? I lost my email and I can't log in to my account. Thank you! *audioactive08*)

I've postponed my reef tank ever since I stopped being a bum and became a full-time dad to a ever-so-adorable 3 month old baby boy. But I'll be starting up a new system and this time it will be for keeps.

(The plan would be some high output LED's for lighting, Sicce, hydor pumps or hopefully vortechs for circulation and the old skimmer I have for filtration... but it's still on the planning stage and I'm not about to start the tank again unless I have all the requisites above.)

Anyways,

Here's a plan for making an external pump from old RC motors or small brushless motors. I'm planning to use this for a pico tank.

Why make them:

-I have lots of motors lying around in the house, from old fans and RC's.
-It's easy to make
-Thermal management I want to eliminate most of the heat sources, one of the biggest challenges in keeping reef tanks is how to stabilize temperature. Since pumps/powerheads give off a lot of heat, having an external pump will be a very good idea.
-Cheap
-I'm getting tired of pumps conking out and crashing my tank and/or electrecuting the crap out of me (if ever this pump breaks, it's not IN my tank)
-A part of a contigency plan in case of power outages, aside from battery operated airpumps


The downsides:
-Range and direction/angle of flow is LIMITED
-Can be unsightly and bulky, depending on the parts you are going to use

Here's a crappy illustration, hopefully it makes some sense:



A prototype of the plan:

I found a 110v, 17w motor from the junk I have.





The propeller is made out of a tin sheet. The motor is very strong anyway so I'm not worried about propeller pitch and balance. I just want to see how much water current this baby can produce.

Questions:

What type of motor would be the best to use and where can I buy one specifically? I'm planning to use a low voltage motor that can be controlled. 12-24v would be nice.

Any ideas where to buy boat propellers? Went to SM megamall before, wala daw sila ng 1.75 na dumas o octura props. (If you guys can remember the stream/maxijet mods posted here you'd get the idea)

Inputs and suggestions regarding this project is very much appreciated. TIA.

[Jake]

bro maybe you could use the pumps sold for over head filters, i remember seeing in a LFS just the motor and centrifugal pump for sale. as for propellers you can try the hobby shops or you can use the fan of and old computer fan. nice ideas you have there. how about using the 7.2v tamiya motors for this, since some of those motors come with bearings so might last for years.

[seth]

Finally, a reply!

Thanks, bro! I'm actually planning to use an old tamiya motor. hehe I'm going to borrow a friend's prop since he's not using his maxi-jet style pump anymore (paging roy_gt). I also have another version, similar to a vortech in principle but not exactly alike. I'm figuring if I could find a controller for HDD/CD ROM motors it would fit well for this project. (And for my little homemade beer/mead project as well. hehe)

While eating at Mc Do I also saw a kid's happy meal toy that may also be useful. It's a little fan with gears and stuff. The things reefers see and imagine. LOL

[phantom]

ever heard/seen a centrifugal-pump?



if you could make a contraption like that, then your problem with flow direction would be solved.

come to think of it, modifying an overhead pump is a good idea I think, coz thats exactly what it uses, a centrifugal pump. you could just attach a flare nozzle to the output feed and you're good to go.




HTH
Cheers!
phantom

[Jake]

@phantom Instead of a flare nozzle why not connect an eductor with flare nozzle to the discharge of the centrifugal-pump. Since the motor is not in the water The heat generated, will just be removed by the built in blower of the motor.

[phantom]

was thinkin that the output flow of the overhead pump is already too strong and was thinkin of the pico setup that I plan to make, thus I din't see the need to use an eductor.

Anyways, great suggestion, will try that once I dig up my old overhead pump from my Arowana days.

cheers!
phantom

[seth]

Thanks for the inputs, guys!

I think I may have found a good solution: gears. I still am on the planning stage but I think it's pretty doable. Imagine the many uses of this little contraption.

Anyways as for the other version, I made a quick prototype out of HDD magnets, an old powersupply fan, 2 plastic bottle caps and a makeshift propeller out of a round plastic junk.

Here's something for the lulz

[Jake]

@seth Coud you send another pic, this time sideways so we can see better.

[seth]

[seth]

Here's a quick update. It works, but still needs more tweaking.




I'm still waiting for my countersunk neodymium magnets so no updates till then.

I was researching about external-driven pumps when I stumbled upon this site:

http://www.maglifeusa.com/mag_jet_mini.swf



Surprisingly, it's been around for years, way earlier than vortech.
As soon as I'm done with the stream pump, I'll be doing an external-driven return pump. But that could take years.

[phantom]

wow! great find on the MagJet Mini.

hoping that it's available locally. hehehe

[seth]

[seth]

Did a bit of tweaking. I still have to work on the motor though. I'll try to post a video of it in operation if ever I have time. (I'll be on a month-long vacation at Leyte this coming June so I won't be able to post. hehe)


Added a rubber o-ring for grip.


Replaced the ceramic shaft with a plastic one made from a stylus, and replaced the improvised prop with a plastic prop from a broken sunsun pump.

I also made some plans for an external-driven return pump, the biggest problem is finding a suitable motor.

[seth]

Let's keep the ball rolling:

If we are to make a simple external driven pump, (similar to vortechs) these are the things to consider:

-type of motor to use, how much torque and how much rpm: we can't use PC fans, that's for sure. Hindi nila kaya yung bigat ng magnets, plus yung resistance ng pagikot ng propeller. But PC fans can be used to make a nice kalkwasser stirrer.

-size/footprint

-cost and controllability: in theory, we can just use a 650peso, 220v mini deskfan, remove the metal blades and stick a ring neodymium magnet then let it spin, we don't need a controller since it already has one. But it will be bulky and ugly as crap, and the parts being exposed will pose as a safety hazard. This is the hardest part, finding a nice motor that could operate efficiently, can be easily controlled and will be inexpensive.

We can use BLDC motors or Modified CDROM and HDD motors, they are efficient, small and can br easily procured from old HDDs or broken CDROM drives. The main problem is the controller.

Another issue will be heat, since pumps are used in tanks 24/7, we will need something to cool the motors or else they will fail. Submersible pumps do not have this problem since the tank water itself serves as a coolant. Aluminum casings plus heatsinks can be used for this purpose.

If someone knowledgeable with RC cars, electronics and DC motors can chime in, the better. We can even make an external DC return pump, provided all materials are available.

Ideas and suggestions are very much appreciated.

[obet_carlos]

ilang rpm ba ang typical? search ka sa ebay.. use "high torque 12V motor" or "high torque 24V motor".. madami lalabas.. may mga controller na.. nakasulat lang yung rpm.. meron dun 300rpm? enough na ba yun? eto yung mga DC geared motors.. kaya mataas yung torque nila kasi may gears na sa loob.. hindi naman ganun kamahal..