Team:Cambridge-JIC/Design

3D Printing

© All About 3D Printing, 2015

The majority of the microscope parts were printed using a MakerBot Replicator Mini and an Ultimaker 2. These have RRPs of around £1,200 and £1,300 respectively, making them the most expensive aspect of the microscope project. However, this is relatively cheap in the context of standard laboratory hardware and once purchased, it can also be used for plenty of other projects.

The printer has 200 micron layer resolution. This is sufficient for the detail of the microscope chassis, optics bench parts and stage. The much finer detail of the Epi-illumination cube means that a printer with higher resolution may be necessary. As the name suggests, the printer is relatively small. It has a build volume of 10.0cm W, 10.0cm D and 12.5cm H. It comes with its own printing interface software, and is compatible with .stl files.

OpenSCAD Design

We are using an open-source software called OpenSCAD to design our components. Here the focus is on the CAD aspect, making it extremely powerful for designing machine parts. It is not an interactive modeller, and instead reads a script and compiles a 3D image. This allows configurable parameters to be programmed in to the designs.

When creating lens holders for the Optics Bench, this became extremely useful as the parameters for each lens could be filled in individually. A single design was readily modified to make each individual component. The software outputs .scad files, which can then be converted to .stl for printing.

Useful Software

Below is a list of software programs that we have found useful for developing open-source hardware, supplemented with other commonly used programs:

  1. OpenSCAD – a free, open-source, parametric CAD platform used to design 3D objects for printing (available from here)

  2. Tracker – a free, open-source, video analysis and modelling tool. Used to track moving objects in videos and extract data (available from here)

  3. Cura 3D – a free, open-source 3D printer interface from Ultimaker. Used to control printer settings (available from here)

  4. Fiji - a free, open-source image processing and analysis platform. Particularly useful for microscopy (available from here)

  5. Inkscape – a free, open-source vector graphics package. Extremely useful for 2D design followed by linear extrusion (available from here)

  6. DesignSpark – a free electronics design software for PCB prototyping. Has an online library of over 80,000 parts (available from here)

  7. Scribus – a free, open-source graphics software. Particularly useful for publishing (available from here)

  8. Python – a free, open-source, programming language that allowed us to put together software quickly

  9. Nginx – A FOSS lightweight web server on top of which we built our web interfaces.

  10. OpenCV – A FOSS released under a BSD license that provides a library for image processing software (available from here)

For a detailed list of free, open-source software programs available, look here.