DIY Dual Head Peristaltic Pump help

[Pbrown3701]

So i picked up a couple of these heads off of ebay for 20 bucks.

http://www.coleparmer.com/catalog/pr...u=0703521&pfx=

My idea is to get a cheap motor that will turn them and then a timer to control the amount of 2 part added.

From the website, i found that you can connect the two heads together and run them off of a single pump. The pump torque needs to be ~100-120 oz in and I want something like 1rpm.

I've looked on the internet for cheap DC motors and I haven't found anything really. Ideally, the motor would have a NEMA 23 mounting size (as that is what size the brackets that are currently on the heads are). For simplicity, i'd like to just run a simple gear motor.

However, i've found that most NEMA 23 sized motors are stepping motors - which i don't have much experience with. The little research i've done shows that they require somewhat expensive control boards.

SO my questions are:

1. Does anyone know where i can find some cheap inexpensive DC gearmotors that run about 1-5 rpm and have 50 or 120oz in torque rating?

2. Is there a way to make an extremely simple controller for a stepping motor? I don't care about changing the speed or monitoring the stepping distance or rate. I just want to set it at 1rpm and have it run whenever power is supplied. Is this easy?

Thanks in advance for the help.

[Donw]

Yup go to lowes and buy two of the smallest charbroil rotiseries. They will turn the pump heads and you can control them with a timer.

Don

[Pbrown3701]

Don, will they turn both together? I'm planning to connect the two heads and run them from a single motor. It will require ~120 oz in of torque

[Donw]

I dont know how your pump heads connect to the motor. Does each head just have its own drive shaft or are they connected together? Can you get pics?

[Pbrown3701]

Here is the part that Cole Parmer sells: http://www.coleparmer.com/catalog/pr...u=0701305&pfx=

I think they just snap together. I think each head has a shaft and "acceptor" on the back for the shaft of the other.

The actual pic of what i purchased is here:

[Pbrown3701]

Also, there looks like a good gearmotor i just found at mcmastercarr.com If you search for AC Gearmotor, its the one at the bottom for about 40 bucks. I presume attaching the motor to the pump heads would not be to difficult?

[Donw]

Those look like they would work you just have to find the right shaft coupler. What size is the shaft on the pump?

Don

[Siffy]

http://www.grainger.com/Grainger/items/4LL05

How about that motor to drive your heads? I know it's not DC like you asked for, but that will save the need for a AC/DC brick. The shaft and mounting looks close.

I have heads similar to that and I believe those thumbscrews are 10-32. Just take one with you to Lowe's/Home Depot and check it out on some nuts and buy a 4' piece of all thread. That's what I did for mine, much easier than trying to find thumbscrews in an exact 1/4" length.

As for the shaft coupler, no clue. Mine have slots and blades connecting them.

[Pbrown3701]

Originally posted by Donw
Those look like they would work you just have to find the right shaft coupler. What size is the shaft on the pump?

Don

Not sure yet Don. When I get them, I'll measure. I'm also not quite sure from the pics how the two mount together.

Siffy - thanks for the link. that looks like it would do just fine. It even looks like it could be NEMA 23 mounting...

[Siffy]

You'll probably have to take the heads out of the brackets. And use a longer bolt or the all thread I mentioned to mount them together. Your style may require a set of 4 spacers, maybe not. I can post a pic of my pump/heads if you'd like.

[Siffy]

Eh, why not, it's not like I have anything else to do at 2am.




Sorry the first pic is blurry, but you can see how the heads mount to the motor. The second pic shows how my heads mount to each other. Slots and blades. You can see the slot on the outer head.

[spykes]

look for the hurst 1rpm motors sometimes you can find them on ebay for like 10 bucks. i got mine for 4 bucks and it has 200oz of torque on it. I dunno if 200oz is enough to run 2 of those heads at once though.

[Pbrown3701]

Siffy - The motor you're using is clearly not the one in the link you provided earlier, but i am interested in where you found it and how much you paid.

My problem is i don't think the mounting holes on the head are going to mount to the motor you linked. It could, but it doesn't say NEMA 23 on it anywhere.

I'll probablly have to make a bracket out of 1/2" acrylic or something to line up the shafts.

[Siffy]

http://www.coleparmer.com/catalog/pr...sp?sku=0755370

That's the newer version of the setup I have. But I didn't pay for it. It's nice to have friends in labs that often throw away old working equipment. You should be able to find one for $200-300 on ebay I think. Hadn't looked in a while, but just now I saw fixed rate pumps for pretty cheap ($25-40).

http://cgi.ebay.com/COLE-PARMER-HIGH...QQcmdZViewItem

[Ewan]

I'd just get a masterflex gear motor, and take those brackets off of your peristaltic heads. They'll be up to the task of continuous duty, and you won't have to worry about the keyed shaft that the perisitaltic heads plug in to.

The masterflex equipment is interchangeable. I've replaced my quick-load with a peristaltic head similar to yours.

Ebay usually has loads of peristaltic motors for masterflex heads. Just search masterflex or cole parmer.

[stugray]

I have a 1 RPM AC gear motor that may work. Hurst 2602-001

Here are the dimensions:

http://www.alliedelec.com/Images/Pro...ol_3160012.pdf

Would that work?

I like your idea, but I would go with a DC motor for speed control ( as you first suggested ).

Stu

[Donw]

Originally posted by Pbrown3701
Siffy - The motor you're using is clearly not the one in the link you provided earlier, but i am interested in where you found it and how much you paid.

My problem is i don't think the mounting holes on the head are going to mount to the motor you linked. It could, but it doesn't say NEMA 23 on it anywhere.

I'll probablly have to make a bracket out of 1/2" acrylic or something to line up the shafts.

If those heads are exactly what you are getting they are not the stackable heads. Notice no slot for the drive shaft. If this is the case they are designed to be single head with individule motors.

Don

[stugray]

Also check:

http://www.mpja.com

for motors & stepper motor driver kits. ( motor driver under kits ).

Stu

[Pbrown3701]

Originally posted by Donw
If those heads are exactly what you are getting they are not the stackable heads. Notice no slot for the drive shaft. If this is the case they are designed to be single head with individule motors.

Don

Don, yeah, from the pictures, i'm afraid you're right. I'm hoping once they arrive, i'll see some way to make it work. We'll see.

[Pbrown3701]

Well the pump heads arrived. I decided to just go with some cheap motors i found on ebay and chance it (afterall, the motors were like 6 bucks). They are rated at 6rpm and the pumps are 3.8mL/rev. So every 1 minute, i can dose 22.8mL. I typically dose ~90mL per day each part so i'll run the motors for about 4minutes each day to get 91.2mL.

I then went to Lowe's to get parts for the driveshaft. The motors have a square "female" shaft while the pump heads have "D" shaped male shafts. The solution was to go to the plumbing section to the brass fittings. I used a 1/8" threaded coupler/extender ("close" size); a 1/8" threaded coupler (female on both ends); and a 1/8" cap (cap is a square plug that fits into the motor.

I also had to tap the threaded coupler with a small 4-40 screw that locks in place on the flat part of the "D" on the pump head.

Doesn't look "pretty," but works great. Both motors are identical and the speed is spot-on the same.

I now just need to find out what type of tubing these connectors are for since it's not standard "RO filter tubing" that i had laying around.

What do you think?

[Pbrown3701]

Oh, and for the metal bracket that i made (very roughly i might add ), i simply found a piece of galvanized steel in the decking section - and cut/drilled it.

If anyone's interested, here are the links to the parts -

[Motors

[Pump Heads

Total cost:
pump heads (2) @ $40 plus $15 shipping
Motors $14 + 7shipping
misc parts from Lowes for driveshafts and mounting $12
Digital timers - have some laying around...

Dosing pumps for 2 part TOTAL cost - $88 (compared to $230-350 buying a commercial product)

[Siffy]

Great job tapping a #4 screw . Looks great too since you bought motors with casings. I didn't even notice the coupler wasn't a 1 piece until after reading. Those still look like ice maker fittings. I'd take one with me to HD and check on some tubing. Probably 3/8", which is common to them, but not so much on RO/DI units.

[Pbrown3701]

Thanks Siffy. I'm very happy with the result.

I'll check into the ice maker tubing tomorrow

[Pbrown3701]

One last thing - these motors are a little noisy, but i'll survive for only running them 4 minutes a day. I may put them in a box of some sort to shield the noise if I get a round to it.....we all know how that goes.