3 ms·
Anyone know what scale factor shrinkage you get out of this stuff? I'd quite like to experiment with optical effects, but I don't know what feature size you can
by regularfry 17y ago
Anyone know what scale factor shrinkage you get out of this stuff? I'd quite like to experiment with optical effects, but I don't know what feature size you can get and I haven't got any expanded polystyrene handy for testing.
- aarongough 17y ago"When heated in an oven or with a heat gun, the plastic shrinks by about 5/8ths and becomes thicker and more rigid, while retaining the colored design." http://en.wikipedia.org/wiki/Shrinky_Dinks http://en.wikipedia.org/wiki/Shrinky_Dinks Seems like you would be able to get pretty small feature sizes if you had a really high resolution printer to begin with...
- regularfry 17y agoIt surprises me that 5/8ths is enough of a difference to be useful, but then I guess it's the way it bunches and forms a ridge that's important for the microfluidics, not the absolute feature size. Hm.
- aarongough 17y agoIt didn't strike me that 5/8ths wasn't actually a huge amount until I thought about it. If the ability to form troughs/ridges is the important thing then I think that the PCB etch/make mold technique would be just as useful. But I'm not sure what the smallest feature size is that you can make with this method: PCB etch/make mold method: Laser-print an inverse pattern mask on clear plastic film Expose a UV sensitive photoresist PCB using the mask Etch the PCB Make a polymer mold (or mold the final part) using the troughs/ridges formed by the etched/unetched copper on the PCB I know this method has been used for replicating fingerprint patterns in the past (Mythbusters!) and I remember hearing it being used for a few other things...