Thursday 28 June 2012

3D Printer!

I have a 3d printer! To be more precise, it's a UP! Plus 3D printer, and I got it a few weeks ago but didn't get around to writing about it. Some specs are here on the cool components web site (where I bought it), although the developers are at http://pp3dp.com/. Here's a nice picture I found:

UP Plus 3D Printer

It was incredibly easy to setup. You basically assemble a few bits with a screw driver (provided), install software and plug it in! First time you use it you'll need to calibrate which would be a fairly simple process, except the software has changed since the manual was written which added a small amount of confusion. Either way, it took less than an hour to set up so I was happy.

Now, the software has it's up sides and down sides. A few good points:

  • It takes the extremely simple stl file format, which comes as standard in most 3d packages, and is easy to write code for as well.
  • Very robust - I've thrown millions of polygons at it and it's never crashed
  • Relatively fast. Obviously give it a few million polygons and it runs at 1fps, but its generally good enough just for positioning your model
  • It automatically adds scaffolding to support your model as it's built, allowing you to create models with overhangs

So in general it does what it says on the tin. However it's not exactly a miracle of UI design. Getting the settings right for a given model does involve a little bit of guesswork, but after a few attempts you can generally get it right first time.

Here's a few models I printed in my experiments to see what it could do:

Statue Of David

Some bits and bobs I printed

These images show a few fun tests:
  • A wine glass with an incredibly thin stork, to see how skinny it could print
  • The oval has text on (which says Chris)
  • The plastic square on the motor is modelled to perfectly fit to the axle. I did this on the basis that if I can print a perfect fitting square, I can print a perfect fitting wheel :)
  • A statue of david (top) because my friend broke his
The best of all though is a chain! This nifty model was printed as a single object. Mark modelled it in 3D Studio with the small gaps needed between each chain link. The software automatically places scaffolding to allow it to print, you wait a few hours and... well best shown with a video:


Going forwards I'm going to create MmBot 2's chassis and framework using the printer. First though, I needed to find a decent bit of CAD software, and found it very frustrating. Too many massively complex uber tools or simpler but ropey applications. So I decided to create my own small CSG tool designed for creating pieces of robot, which I'll probably write about next time.

Saturday 9 June 2012

Git Open Source

Very very quick post here - I've finally got around to setting up source control for mmbot. All is open source and stored up on git hub here:

https://github.com/wibble82/mmbot

It currently contains most of my Arduino code so far, and the beginnings of the design for the new chassis using OpenSCad. Feel free to grab what you need, along with the general statement of 'I take no responsibility for what you do with the code even if it blows up a computer or nuclear power station or whatever' :).

-Chris