Part smoothing for 3D printed parts, especially parts printed in ABS, has been around for a while. The process of exposing an ABS part to acetone vapor turns even low-resolution prints into smooth, glossy 3D renderings that are stronger than ever. The latest improvement in part smoothing for 3D printed parts is now here: use a brush. Published in Nature‘s Scientific Reports, researchers at Waseda University have improved the ABS + acetone part smoothing process with a brush.
According to the authors of the paper, traditional filament-based printing with ABS has its drawbacks. The grooves formed by each layer forms a porous surface with a poor appearance and low rigidity. This can be fixed by exposing an ABS part to acetone vapor, a process we’ve seen about a million times before. The acetone vapor smoothing process is indiscriminate, though; it smooths and over-smooths everything, and the process involves possible explosions.
The researcher’s solution is a felt tip pen-like device that selectively applies acetone to a 3D printed part. Compared to the print over-smoothed in a vat of acetone vapor, more detail is retained. Also, there’s a ready market for felt tip pens and there isn’t one for crock pots able to contain explosive vapor. This is, therefore, research that can be easily commercialized.


[Torbjørn Ludvigsen] is a physics major out of Umea University in Sweden, and built the Hangprinter for only $250 in parts. It follows the RepRap tradition of being 
Last week we saw 
The printer design chosen for the project is the Prusa i3. We have certainly seen custom builds of this popular design before using laser-cut plywood for the frame. Still, these builds use 3D-printed parts for some of the more complicated parts like the extruder carriage and motor brackets. To the right is the X-carriage mechanism. It is complicated but requires no more than 6 mm and 3 mm acrylic stock and the type of hardware traditionally associated with printer builds.

