3D Printer Experiments
Posted: Wed, 14 Jan 2015 16:20
One of the great things about the "fused filament" 3D printer we use in the Lab at Phoenix is that you can use it to experiment with different printing materials. It's had wood-based filament run through it recently, as well as flexible BendLay, ColorFabb copperFill and water-soluble PVA.
These newer filaments allow for some quite interesting print effects and let make things that don't initially look as if they have been 3D printed. The copperFill looks particularly impressive once you have sanded-down the model. The PVA has a different use though. On a dual-head printer you can use it to make dissolvable support structures.
Support structures are needed whenever you are trying to print something with overhangs. They consist of thin 'towers' of plastic that hold up the parts of your print that would otherwise sag or collapse if you didn't use them. Support is designed to be removed easily, but this process can take a while and may leave ugly marks on your print.
Enter the idea of using PVA for support. Polyvinyl Alcohol is a polymer that can be turned in to a filament that will run through a 3D printer at a similar temperature to common PLA. When used as a support material for PLA prints it does the job of supporting overhangs during the print but when the printing process is complete there is no need to remove it manually. Instead, you simply pop your model in a bowl of water for a few hours and the PVA support simply dissolves away.
It look us a few attempts to get the process to work but once we got the temperature right the process works pretty reliability. During the build we found that the models can look very messy - the picture attached shows a model that has a mixture of white PVA supports and a red PLA body - but once they have been left in water overnight they look fine.
We obtained our PVA filament from the iMakr shop in London. You'll also find it on eBay.