electric motor for toys cars and other things

[hobbes]

Hello 3dprintboard.

Some time ago, I decided to CAD up all the components of a toy motor that I frequently use in small scale cars. It was primarily just a 3d modeling exercise for my portfolio to keep me busy between jobs. I had no plans to 3d print this.

Now i work at a job that i love, and i have at my disposal a mighty Stratasys Eden260V!
In November, i decided to toss my 3d model on the print tray to see what would happen.

Here's the result:


Apart from the coil, magnet, brushes and commutator collectors (basically all the important metal stuff), everything else is 3d printed.


Before i get to the rest of the pictures, here's a few questions answered right up front:

How fast does it spin? Using a digital tachometer, i clocked at just over 10,000 rpm running it off 2 AA batteries. The winding is far from perfect, so it could have been better. The real motor runs at more than 13,000 rpm with the equivalent wire thickness, and higher performance ones run much much MUCH faster.

How reliable is it? HAHAHAHA! But no, seriously, it's crap. After about 30 seconds it quickly loses speed because the heat causes the thin plastic to warp and then the entire core wobbles. The 3d printed parts are thin because the original parts are manufactured in steel and sheetmetal. The shaft is only 2mm thick.

Why not just make a more realiable print-friendly motor? Because i wanted to replicate a pre-existing, standardized motor. I wanted to be able to print, plug and play, without thinking about how to modify the frame in which it went. Of course...this was before i knew how badly it warped under heat!

But Faraday's law of induction...Eddy current...performance reduction...blah blah BLAH! I did this for fun, not to revolutionize the design of electric motors. Just roll with it!

Here it is next to the original motor, a mabuchi fa-130. You might be surprised how often this little guy gets used in devices/toys. It's cheap, simple and effective.


Details


Fits perfectly inside the motor mount without any modifications. Neat!


Just for fun, i printed a 1:2 scale version. Maybe, someday, i'll try to get the smaller one working.



An assortment of parts.


In December i wanted to test out Shapeway's metal prints, so I sent in the armature. It's a bit rough and out of spec, but it's the right shape!


A drill, some sand paper and some elbow grease will fix this right up.


Shiny!




And this is where i stopped. As soon as my attack of "the lazies" subsides, i'll wind it and see what happens.


Not to leave my Folgertech Prusa feel unwanted, i decided to experiment with her as well. Here's a 5 rotor armature that i always wanted to make. This will take somewhat of a redesign of key components to work, but it's definitely on my to do list, further down the road.


Here are the renderings i made of the CAD model:
http://www.coroflot.com/hobbes/FA-130-Mabuchi-Motor

Here's the grabcad page with step and solidworks files
https://grabcad.com/library/fa-130-mabuchi-motor-1

[curious aardvark]

very neat !

Although this made me laugh:

Apart from the coil, magnet, brushes and commutator collectors

lol - like a reprap printer: 'well it's self replicating apart from: rods, electronics, cables, motors, extruders etc'.

[Mjolinor]

Without laminations on the rotor it will get extremely hot.

[hobbes]

very neat !

Although this made me laugh:

Apart from the coil, magnet, brushes and commutator collectors

lol - like a reprap printer: 'well it's self replicating apart from: rods, electronics, cables, motors, extruders etc'.

I tried getting the commutator and brushes printed, but they're too thin for shapeways, even with their higher end metals. I'm working on a couple of changes that might make them printable and still maintain the outside shape. It's a bummer though: i was hoping to have this fully 3d printed while maintaining the exact dimensions for each component as the original.

As for the magnets, i had thought about using the protopasta magnetic filament and then zap them to polarize positive and negative, but i don't know if that would work or even have a clue how to go about it yet.

The wire...well...i think for this design, we can just leave that as wire.

For this project, i'm strictly trying to stay within the size and shape of the original motor, however i'm also working on a concept for a larger, non-standard motor that would be in fact 100% printed, including the coil.

[3dex ltd]

Your motor looks absolutely fantastic.

We are always on the look out for really interesting prints and so we shall print this and give it a try when we next have a second. Have you realised the .stl files yet?