3D print Silhouette Lamp
This project's goal was to test if it is possible to print a silhouette lamp with the 3d printer. A silhouette lamp's main characteristic is that light shines through a decorative pattern of darkened regions. Usually this is achieved by a opaque print on a translucent material.
The first test was to see if the 3d print material could be printed thin enough to be translucent enough to let light through - and still be sturdy enough to be handled before it was dipped into the hardener. We determined that the best way to keep the fresh print from crumbling was to support the 1mm thick sides by adding a "frame" and by thickening the silhouette pattern instead of just printing the pattern. Test samples of .8 mm and 1mm were printed. Despite the tiny difference in thickness, the .8 sample is outspokenly more transparent. So transparent the the pattern is visible from the other side even when the sample is not held up to the light.
This particular lamp is a prototype of an outdoor solar lamp concept by Rebecca Potger. It has the shape of a birdhouse, and the silhouette pattern is that of a bird with foliage. The silhouette pattern had to be redone in such a manner that all sides of the lamp are supported sufficiently.
The lamp was modelled in a 3d cad application. The wall thickness was made 1m according to findings of the test.
Due to the lamp's large dimensions, it was left to print at night. The printing took about 8 hours so it had time to dry until the following morning. Seeing as to how easily I damaged it when I attemped to clear it of powder, I shudder to think at how fragile it would have been without this drying time. An observation is that an impression of the pattern was visible on the other side.
Vacating all the unused powder was very tricky. We are not sure if the damage to the lower part was due to me accidentally touching a part with the vacuum nozzle or due to the weight of powder pressing on one side of the thin wall. The damage on the roof part was definitely due to a slip-up! After depowdering the print was place in a oven (50 degrees) to dry some more.
Dipping the print in hardener was equally tricky but nothing unexpected came up. We did have to dip one side at a time. The print was left in the oven again (50 degrees) to facilitate drying.
The prototype was finally completed with the addition of the leds and solar panels taken from a standard garden light.
So the conclusion is... the print material is definitely translucent enough for a silhoutte lamp. Handling large prints with a 1mm thickness is tricky but manageable with a steady hand.
A second test with 1.2 mm thickness was later made without any problems whatsoever. The .2 mm difference in thickness made a huge difference - the print just felt a whole lot sturdier. It did make the material a little less transparent, but the silhouette was still perfectly visible when lit up by the two LEDS.
