3D Printing Large Parts

Building large parts using 3D printing can be a problem because of the limitations on the build envelope of the 3D printing machine. The build envelope is the Length x Breadth x Height of the space in the machine where the material is printed. Normally people build large models in parts and then stick them together. For that you need to cut the 3D model into parts in some software and maybe add corresponding protrusions and holes on mating surfaces so that the people sticking the parts together align them properly.

Yesterday 3D Systems announced the availability of single piece, extra large parts through their 3Dproparts service. Here is a 59 inch long turbine blade that was print3d on a 3D Systems iPro 9000XL SLA production printer which has a build envelope of 59” x 29” x 22”.

When I was at the 3D Systems HQ in Rock Hill, SC, I saw some of these large machines in action. I think the largest of them costs somewhere close to a million dollars or so.

Here is a video showing a 3D Systems iPro 9000 XL printing a dashboard. I don’t blame you if you think that the video is as boring as watching paint dry. That’s because you actually are. 😉 The Stereolithography (SLA) process is all about using a laser to solidify photo curable resin. In the video the light you see moving rapidly on the top surface of a large resin vat is actually solidifying the resin. After the laser is done criss crossing the vat, the vat is lowered by a few microns and fresh liquid resin covers the solidified portion. As you can imagine this doesn’t happen evenly across the vat. So a wiper blade sweeps across the top of the vat skimming the top and evenly spreading the resin all over the top surface of the vat so that the laser can solidify the next layer of resin. The whole process repeats itself till the entire part is printed from bottom to top.