123D Elephanticus

Elepanticus minus support material

Most of the support material has now been removed and he doesn’t look too bad. Next step is to have the Elephanticus painted.

After a 10 hour print at 0.254mm layer resolution this is what the Elephanticus looks like pre-soak. Most of the support structure should break away after a couple of hours soaking.

Original images on our Flickr.


123D Creature – Character Design

123D Creature is a new iOS app from the team at Autodesk that allows students with no previous experience to engage and experiment with 3D modelling. 

Creatures are the name of the game and the app provides an intuitive interface that is easy to use. Starting with a skeleton, it is very easy to add limbs, bones & joints , sculpt details much like you would if working with clay. 


Processing your model or ‘baking’ as 123D Creature refers to it, allows you to add textures, poses, scale, colour etc. and to place your model into a background to produce photorealistic renders. 

I think it’s awesome.

Creatures can be exported in .obj format, and if you have access to a Makerbot 3D printer, you can import the .obj directly into MakerWare and start your print job. If you don’t have a Makerbot, you will need to import the .obj into blender and export as a .stl – the file format required by most 3D printers.

This is the scenario I am going to give students:

123D Creature Project

Download your own copy of this unit of work.

Thingiverse already has a number of exemplar models available to download. We are currently printing the Elephanticus on a Dimension 1200es series with layer resolution of 0.254mm – estimated build time of 10 hours.

Will post updates when done.


As part of PLANE’s month of gaming series, I mentioned briefly how the Cult of Done Manifesto had greatly improved my productivity and outlook on work/life. Reproduced here:

  1. There are three states of being. Not knowing, action and completion.
  2. Accept that everything is a draft. It helps to get it done.
  3. There is no editing stage.
  4. Pretending you know what you’re doing is almost the same as knowing what you are doing, so just accept that you know what you’re doing even if you don’t and do it.
  5. Banish procrastination. If you wait more than a week to get an idea done, abandon it.
  6. The point of being done is not to finish but to get other things done.
  7. Once you’re done you can throw it away.
  8. Laugh at perfection. It’s boring and keeps you from being done.
  9. People without dirty hands are wrong. Doing something makes you right
  10. Failure counts as done. So do mistakes.
  11. Destruction is a variant of done.
  12. If you have an idea and publish it on the internet, that counts as a ghost of done.
  13. Done is the engine of more.

The salient points of the Manifesto, for me at least, are 4. & 5.

4. because it helps you overcome those moments of the fear of not knowing, the fear of failure, the feelings of not being up to the task or that someone else knows more or could do it better.

5. because it has helped overcome my Chrome tab addiction. Seriously, sometimes I would have the same 20 tabs open for a week. That’s not healthy. If you haven’t read or acted on those tabs within 7 days then you are not going to. Delete them. If it is a good idea it will find it’s way back to you.

I promise.


Want to make a DC Motor?

Today we utilized a 3D printed split-ring commutator with adhesive copper tape making contact with the brushes. We were expecting greater efficiency, but actually got less. The copper foil we are using isn’t ‘springy’ enough – a new brush system is needed or at least some thicker copper foil. (Granted it only has 2V through it in this video) Check it out.

Something else to consider when using 3D printed parts instead of balsa is that the extra weight causes the shaft to sag… If using 3D printed parts consider using something other than a wooden skewer – maybe a metallic skewer, knitting needle etc.

Find ‘Making a DC Motor’ Activity sheet available from download here, which also includes .skp files for the armature and commutator.


We are currently working on a 4-pole DC motor. Two commutator’s will be needed placed 90 degrees out of phase to ensure maximum efficiency. (We think.)


4-pole armature

*Instructions for a simpler DC motor can be found here.

Making a DC Motor

A rough sketch of a DC Motor.

DC Motor Sketch

Having students construct a simple DC motor is a great way to learn about the interactions between electric & magnetic fields.

Materials needed:

  • Pine from your local hardware store
  • Wooden skewers 
  • Horseshoe magnet
  • Split pins
  • Enamelled copper wire 0.5mm
  • Copper foil (I used 0.1mm thickness but recommend probably around 0.3mm)
  • Balsa wood for shaping an armature (or a 3D printer to print an armature as we did in this example)
  • Masking tape
  • Razor blades

The Armature is easily made by shaping some 25 x 25 mm balsa with a razor blade. Getting a nice balanced armature can be tricky and requires some patience. If you have access to a 3D printer you can have students design an armature using Google Sketchup. Once printed, it can be placed on the shaft and copper can be wound around the armature.


Also note that the copper wire must be enamelled. The enamel then should be sanded only where the brushes make contact. The enamel works like insulation in the coil and allows a force to be generated.

End Result:

Next Step:

To create a split ring commutator with adhesive copper tape so that our motor looks a little more like an actual motor. ie.