Peristaltic pump success?

[Mike Schoenborn]

Has anyone printed any of the peristaltic pump designs out there?
Some look clever, some look pretty, some look actually functional.

I'm looking for the latter, one that would fit a junk box stepper, for
delivery of "3 to 8 drops" of a liquid coffee sweetener. Just a Rube
Goldberg pastime project.

Experiences?

Mike

[Ethan Dicks]

On Wed, Sep 2, 2015 at 11:50 PM, Mike Schoenborn <rt...@columbus.rr.com> wrote:
> Has anyone printed any of the peristaltic pump designs out there?
> Some look clever, some look pretty, some look actually functional.

Someone in the group printed one and gave it to me. It split along a
layer, but it looks quite glueable. I have not tried running it off
of a drill yet.

> I'm looking for the latter, one that would fit a junk box stepper, for
> delivery of "3 to 8 drops" of a liquid coffee sweetener. Just a Rube
> Goldberg pastime project.

That sounds like a good use of one. I think given the speeds and
torques involved, a popular way to spin these is an electric
screwdriver with a 1/4" hex bit that mates into the pump. The amounts
dispensed wouldn't be as precise as with a stepper, but a simple
magnetic or optical rotation sensor could help that.

-ethan

[Bill Schwanitz]

The pump I tinkered with is http://www.thingiverse.com/thing:454702 ( same one Ethan is speaking of ). The code being in openscad means its highly tweakable - at least to me.

Search on thingiverse, there are plenty of designs out there. The biggest challenge I had was getting the diameter of the tubing translated in to the openscad to make the pump gear printable. Also note that the gear/pump prints as a single unit - I chucked it in my drill to break the gears loose and then it was great.

Depending on the material you print in be careful. When I reved it up in the drill to loosen things up the friction generated caused the plastic to get soft ( pretty sure I printed it in pla ). It did work pretty well though