DIY 12v DC mag-drive pump?

[ejmeier]

Having seen the Red Dragon pumps, I have always been wondering how hard it would be to DIY a DC pump.

Today I stumbled across a site that had what looked to be some DIY pumps for sale, for the PC cooling market.

Taken from this site: http://www.cooltechnica.com/Merchan...uct_Code=AQX-50Z-DC12-T&Category_Code=DC-Pump

I couldn't help but think how easy it would be to make one of these for special applications/projects. I bet you could fabricate a housing out of pvc/acrylic fairly easily. (Or not.) Worth a try though.

Does anyone know where to find just the guts of a DC-powered mag drive motor? Like in the picture above - pretty much just the blue part that has the sealed mag-drive part. I tried searching on www.globalspec.com (really well laid out site BTW) but there are enough choices to make your head spin.

 

[dattack]

Well the ones Bubble Kings are working on runs at around 24V and RPM 0-5000.
This pump would work but the flow is kind of low. There are tons of DC pumps out there but the hard part is finding the right one for our application.

 

[moriartiholmes]

Wouldn't DC be more of an electrocution threat than AC?

 

[douggiestyle]

<a href=showthread.php?s=&postid=6730694#post6730694 target=_blank>Originally posted</a> by moriartiholmes
Wouldn't DC be more of an electrocution threat than AC?

Thomas Edison didnt believe so.

 

[ejmeier]

<a href=showthread.php?s=&postid=6730694#post6730694 target=_blank>Originally posted</a> by moriartiholmes
Wouldn't DC be more of an electrocution threat than AC?

AC = 120 volts
DC = 12 - 24 volts (give or take)

If I had the choice, I know which one I would rather have shock me.

 

[douggiestyle]

contact with the 115V line from dry hand to dry hand, which has a resistance of 2300 ohms, will result in 50mA flowing in the arms, chest and head. But at the end of three seconds there will be 230 mA due to blisters forming at the contact points.

Current is main killing factor in electrical shock. The voltage is important only in that it determines how much current can flow through a given body of resistance.

 

[moriartiholmes]

Edison had to sell his DC generators etc. and created the electric chair (AC) and fried elephants to disprove Tesla and AC. There was a definite business side to his being against AC. Sorry to rant on Edison, but the guy seemed like a jerk
I'm not an electrician so I'm not really sure, but it seems like a car battery has more "kick" than an ordinary outlet. Personally, I don't want to be zapped by either.

 

[douggiestyle]

<a href=showthread.php?s=&postid=6731170#post6731170 target=_blank>Originally posted</a> by moriartiholmes
Edison had to sell his DC generators etc. and created the electric chair (AC) and fried elephants to disprove Tesla and AC. There was a definite business side to his being against AC. Sorry to rant on Edison, but the guy seemed like a jerk

such a jerk, tesla quit working for him and went to george westinghouse

 

[douggiestyle]

you could use a fan motor from a car. just attach some sort of pump to it.

 

[brandonberry]

Boat bilge and livewell pumps run on DC and come in all different flow rates. They can be bought from places like westmarine.com

 

[ejmeier]

After looking around, I found a few interesting things, but still nowhere near what I am trying to find.

Turns out Iwaki makes a DC-powered line of pumps, their "RD" line. I saw a RD-05H that was this tiny little thing, probably smaller than most powerheads. Not many places sold them, but when I did find one: the cost? $200! :eek2: That pump was exactly the type of thing that I want to make myself, but at about 1/4 the cost.

Then I found that March Mfg. makes a DC-powered line of pumps too, their 893 line. This diagram helped me see how these things are put together:

Referring to the pic above, basically I am after a unit that has parts 7-13 all in one finished unit. I don't need 1-6 and want to DIY those parts. But, all I can really find is places that will either sell:
a) parts 1-13, the whole unit, for a really high price
OR
b) just part 12, the DC motor, which makes it really hard to DIY the whole body of the pump.

WHY DO I THINK THIS IS FUN???? I think it would be cool to see if you could completely DIY a mag-drive pump. I'm probably dreaming, but it seems like a fun challenge.

 

[dattack]

Check out this pump. The only problem is that it's meant for intermittent use.

It runs over 3000 gph and at around 24V it should be less than 150 watts.

 

[stugray]

What about a linear actuator driving a huge piston?

The actuator could be servo, stepper, whatever you want, but would need to be geared down for power.

If you want constant flow in one direction, you couple two pistons together ( and two drives ) with valves. If you want oscillating current you use one piston, and no valves.

Stu

 

[ejmeier]

<a href=showthread.php?s=&postid=6734595#post6734595 target=_blank>Originally posted</a> by stugray
What about a linear actuator driving a huge piston?

The actuator could be servo, stepper, whatever you want, but would need to be geared down for power.

If you want constant flow in one direction, you couple two pistons together ( and two drives ) with valves. If you want oscillating current you use one piston, and no valves.

Stu

Occupation: Spacecraft Integration Engineer

No clue what you just said.

At this point, I am feeling a bit dumb. Maybe DIY a DC is out of most DIYers range. There must be a reason why only Tunze and Red Dragon make DC pumps, and they cost TONS.

dattack - what pump is that?

 

[brandonberry]

That is one of those boat pumps I mentioned, made by Rule.

 

[dattack]

<a href=showthread.php?s=&postid=6736154#post6736154 target=_blank>Originally posted</a> by ejmeier
Occupation: Spacecraft Integration Engineer

No clue what you just said.

At this point, I am feeling a bit dumb. Maybe DIY a DC is out of most DIYers range. There must be a reason why only Tunze and Red Dragon make DC pumps, and they cost TONS.

dattack - what pump is that?

http://www.cisolar.com/catSubPumps.html

 

[ejmeier]

Heh, I just saw that with a little bit of searching. Those #s are very energy efficient, but thing with these is that I think there are actually direct-drive pumps, so the shaft is linked directly to the motor. Sort of like pond pumps. Motor isn't really sealed then.

I was also looking at the livewell pumps, and it would be absolutely perfect for me - but I think they are direct drive too. They refer to the motor as a "cartridge" so I'm guessing that it is pretty much a disposable pump. (Looks like you just keep the outer inlet/outlet plumbing intact and swap out the rest of the pump.) Otherwise, it would be a great find.

EDIT: Here's a link to one I was referring to:
http://www.westmarine.com/webapp/wcs/stores/servlet/product/10001/-1/10001/144275
You can see the little blue impeller sticking out the bottom. You can also see near the top where the o-ring seals the motor to the inlet/outlet cover (not pictured).