Printable Motors

Is anyone here working on the concept of printable motors, as a direct replacement for the steppers used on Mendel?

I have been tinkering in Inkscape with some designs based around a 4 slot Geneva wheel, driven with a 3 pin drive wheel. The Geneva wheel is then futher geared to give appropriate steps per revolution.

The use of a Geneva wheel should make it possible to be more efficient as no hold current would be required, however might slow the speed down too much (compared to the normal stepper).

Any comments?
Simon

Some more 'tinkering' has adapted this idea to a 3-slot geneva wheel with a 3 pin drive wheel, giving 120 deg per 'tick'.This would have to be reduced 66 2/3:1 to give 1.8 deg steps (200 per rev), which could be achieved by a 3 stage gear box (4:1 + 5:1 + 10:3).

Anyone have suggestions regarding the blacklash on the gears, what are 'we' able to achieve in printable gears of these ratios (and no bigger than, say, 30mm dia).
Simon.

Hopefully the Spoolhead should open up the possibility of printing electromechanical parts... if it works!

What drives the 3 pin drive wheel?

I think that a pneumatic stepper motor would be far more printable.

Bent Valerius Wrote:
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> I think that a pneumatic stepper motor would be
> far more printable.

The problem then is making the control valves, that will seal adequately.

Hypothetically, to print a DC motor you could print the coil harness (looks like a "Y") with a gear on the end then a 2-part case with two magnets on the left and right sides to make brushes put conductive paint on 4 "brushes" and then solder wires then wrap coil around core and proceed (superglue/hot-glue) case together around the innards and connect wires to controller.

To make a stepper motor however would be much harder to print though it would be possible

Note:I do not currently have a reprap so could someone please attempt a reprapable DC "proof of concept device" and publish, on this forum, the results and design of your motor. Thank You

I think the easiest motor to design for printing (Though not to drive) is a Brushless DC motor or BLDC.

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Necessity hopefully becomes the absentee parent of successfully invented children.

The only printable motor designs in my head right now would be to use a solenoid type coil to nudge a ratchet mechanism. You would probably need two coils to spin things in both directions. The coils are the most practical type of motor coil to hand fab. We could print the spool, and we could also print the spool winding machine.

You sill would need to get the enameled wire. I don't see extruding copper wire anytime soon.

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My blog's Reprap feed: [blog.markbova.com]
I'm currently working on a stock Mendel build with a Seeeduino Mega and four Pololu A4983 stepper controllers.

There are many different candidate designs for printable motors. There is a big overview here [www.reprap.org], including ratchet-type designs [www.reprap.org].

Also promising I think are solenoid-driven rotary motors [www.reprap.org].

A while ago I posted a somewhat-printable motor design here [www.thingiverse.com]. Technically I guess it would be called a brushless DC motor, but it can be driven like a stepper motor or a DC motor depending on how it is configured. Not very much torque though...

-Matt