Anyone DIY a Dosing Pump?

[MidwesternTexan]

I would DIY a dosing pump,
except that I drip a Kalwasser/vinegar mix in to myh sump every day and that keeps my Reef happy! Hard to go wrong with this

 

[EnderG60]

is this the item specifically?

http://www.ebay.com/itm/DC12V-Peristaltic-dosing-Pump-Tygon-LFL-6mm-ID-tube-and-can-deliver-500ml-min-/281596744025

looks like a plain & simple DC motor on the back of that thing, I would imagine a speed controller could slow it down, but how slow & what flow? might be worth buying one to play with

Not sure if you've come across these but from all my research it appears that Cole Parmer Masterflex Peristaltic Heads are the last word in peristaltic pumps, the only problem I found is the AC pumps they run on are a bit cumbersome and overkill for our purposes so I started looking into adapting a geared DC motor to them but locating a compatible shaft or even a way to adapt the drive shaft was a dead-end for me.

This is an example:

The first set of dosing pumps I made used those heads. I still have them. They are amazing heads. The problem I had with them was they require some serious torque to turn them. The motors I found with the right RPM and torque ended up being close to $40 alone, and I had to make a shaft to connect them to the heads.

After about 18 months the motors started to go out on me and I opted to try a new setup with the ebay heads instead.

If a more cost effective motor and shaft option could be found I would reuse those heads in a heartbeat.

 

[HiFidelity]

can you share the specs on the motor? I assumed by the size of the original motor that they would require some amount of torque which is what lead me to researching geared DC motors, considering that speed is not a concern the correct gearing paired with this head would allow a DC motor to work well within it's efficiency thus resulting in normal working life. (I could be wrong since I don't actually have this head in my possession)

 

[zachts]

I'm running a DC motor driven set of three CP heads stacked on one motor (came that way on ebay, what a steal for $40 a while back) Sadly I've never found powerfull enough geared motors to operate them for less than $30. Pittman-Ametek makes good ones that are fairly common on ebay and robust as hell. The motors I've got are 65.5:1 gear ratio, 24 volt and show up once in a while new on ebay. gear motors are in general noisy though especially at higher RPM, for dosing use they'd run pretty quiet in most cases though when slowed down with a PWM controller.

If memory serves the motor and gear box need to provide around 350 in/oz of torque to run the CP heads with norprene or pharmed tubing. silicone I recall needed around 200 in/oz.......

You can more than likely order adapters from CP for connecting the pump head to a motor shaft......they probably aren't terribly cheap though.

 

[dartier]

If memory serves the motor and gear box need to provide around 350 in/oz of torque to run the CP heads with norprene or pharmed tubing. silicone I recall needed around 200 in/oz.......

Hmmm, 350 in/oz you say? I have some 425 oz/in NEMA23 steppers that I bought awhile back and never got around to using ...

As for an adaptor, I am pretty sure I can ghetto up an acrylic adaptor for an aluminum hub on my CNC. If that proves to be too fragile I'll have to get my brother to cut the real thing out of aluminum.

Sigh, so many projects, so little time.

 

[zachts]

Sigh, so many projects, so little time.

I second that!

:beer:

 

[HiFidelity]

I second that!

:beer:

Third :uhoh3:

 

[djbetterly]

Where do you stand with this project? I built a wifi one a while back using AC pumps. I also found two good sources for pumps, one in china another in japan. Let me know if you need any help. I've tested a lot of different pumps, and its pretty amazing how much they all vary.

 

[dartier]

I totally forgot about this thread. DIY dosing is one of my favourite topics and when I happily clicked on it to read it, I found that I had already posted into it. :spin1:

I have been working on a new dosing system (in my head) for a DIY alkalinity tester (from another thread) and ran across some old videos of my previous attempts, so I thought I would posted them here since it is on topic.

This first one is was a proof of concept for using motion control hardware for DIY dosing. The 'arm' in it was hand fabricated with a hacksaw, drill press and lots of filing. The wobble is due to the quality of the linear stepper motor driving the threaded shaft. Even with the wobble it gave me confidence that you could achieve very precise dosing, so I set about designing one.

<iframe width="560" height="315" src="https://www.youtube.com/embed/TiodATKWx5s" frameborder="0" allowfullscreen></iframe>


This is what I built after the proof of concept. I decided to build an 11 position polar syringe doser. Each position has a uniform pocket milled into it that can accept a colour coded adapter and cover. Each colour is sized for different syringe diameters/flange sizes. The parts were cut in acrylic on my CNC. It worked, but my belt retention mechanism needed a re-design and I have never got around to re-doing it.

If I were to do it again, I would use 2020 extrusions, which is what I am planning to use on the new version. Sorry about the orientation, it is the only video I have of it running.

<iframe width="420" height="315" src="https://www.youtube.com/embed/_GOCpZgP70Q" frameborder="0" allowfullscreen></iframe>

Dennis

 

[DrakeFrst]

Hmmm, 350 in/oz you say? I have some 425 oz/in NEMA23 steppers that I bought awhile back and never got around to using ...

As for an adaptor, I am pretty sure I can ghetto up an acrylic adaptor for an aluminum hub on my CNC. If that proves to be too fragile I'll have to get my brother to cut the real thing out of aluminum.

Sigh, so many projects, so little time.

I totally agree with you. Thank.