3D Printing – Slicing Software and Tools
You’ve spent time on your latest creation in zBrush, Blender, Silo, TinkerCad or and of your favourite 3D modelling software, or like me if you can find it on Thingiverse then jobs a good un!
Whatever you use for your prototyping your creations, you’ll eventually want to print it, but how? Of course you can use a number of online 3D Print services, and pre-printer days, I’ve had a lot of success with the services (albeit costly). There’s more fun to be had seeing your creation come to life, line by line.
You’ll need a Slicer, which is basically software that renders the 3D model on a base plate and then slices the model layer by layer at a height you’ve determined. For fast draft prints, a layer height of 0.2mm – 0.3mm is acceptable, for fine detail you may need to drop layer heights to 0.06mm to 0.1mm, doing so will significantly increase your print time. If you’re printing something large, don’t be surprised that your printer will take 24 hours or more.
Slicer software has improved significantly over the years, with open source becoming more advanced than paid solutions in many cases. Some of the most popular titles include :-
- Cura – https://ultimaker.com/software/ultimaker-cura
- Prusa Slicer – https://www.prusa3d.com
- OctoPrint – https://octoprint.org
- Slic3r – https://slic3r.org
- Repetier – https://www.repetier.com
- Simplify3D – https://www.simplify3d.com
Although I purchased Simplify3D which had good reviews, I find myself going back to Ultimakers Cura software which is available for macOS and Windows and has handled most of the jobs I’ve thrown at it.
Whatever software you choose, you will need to fine-tune and tweak the profile settings. For reasons unknown the default profile for the Cura Geeetech A20M assumes you have direct drive print heads and not the Bowden tubes that are installed by default. Therefore it’s important you calibrate your printer first to find the optimal retraction settings. In my case it was about 6mm at 40mm/s.
Slicers will also identify parts that are impossible to print without some form of support (Tree or Pillar). For example, hands which are in mid air, the software will generate support structures that you typically break off, or you can print in PVA Glue which will dissolve in water leaving the final model. The green lines shown below are the supports that will be printed to ensure the body, hands and glasses can be printed since they are in mid air. Of course you could print your model in parts and assemble afterwards.
Before you start a major project, experiment with your slicer software and printer to not only find what’s optimal for the printer model, but to tune the printer to the best you can to avoid long prints that may fail at the final hour.
As you can see the final test print needs some further work, sanding, filing and cleaning up. This is an example of a bad print, there are issues I need to address such as retraction rates. PVA Glue strings quite badly as it has a different melting point than PLA, thankfully PVA dissolves in warm water.
To be continued…