Last week, we launched customizable cufflinks 3d printed in Stainless Steel. It’s a cool material (you’re 3d printing in METAL!!), and we want to share some information on the process.
There are a few different ways of printing in Stainless Steel. The method used for our cufflinks involves first binding stainless steel powder with a glue. A layer of stainless steel powder is spread out, a print head drops bits of glue over the layer. After the glue solidifies that layer, another layer of powder is spread out on top. This process repeats until the objects are made.
Afterwards, a technician carefully extracts the solid parts (parts of the powder glued together). The technician vacuums away the leftover powder, which is reused in the next batch. At this point, the models are in their “Green State.” The parts are solid, but quite brittle. Models that are too fragile often break during this stage. It is a just a little stronger than wet sand people use to make sandcastles. So here’s a tip—when you’re designing, think: what if I made this with wet sand, will it crumble? The video below (from Shapeways) shows how easy it is to break parts in this Green State.
The models are then affixed to a long beam using sprues. Each beam is attached to a pool of liquid bronze and heated in an oven. These parts are quite porous and soaks up the bronze like a sponge. This accounts for some slight coloration differences. The parts on the beam closest to the bronze pool will be a little more bronzey, the parts on the other end will be a bit more silvery. You can see the range of stainless steel coloration differences here.
When the parts come out of the oven, they are fully strengthened. Remember that video of me crushing the models with my fingers? Can’t do that anymore after they come out of the oven!
Last, technicians cut each part from their sprues and polish the models using a tumbler. They put the models into a big tank containing little pieces of media rubbing down the rough surface of the stainless steel—different types of media are used depending on the geometry. In the Tumbler, the media vibrates and smooths the surface of each object. A technician then applies a sealant after the model is polished to finish off the process.
Cool eh? Shapeways, our production partner, made a video that summarizes the process of 3d printing stainless steel.
If you are interested in learning more about designing for 3d printed stainless steel (or any materials), leave a comment or email us. You can also head over to the Shapeways materials pages and check out more information there (an amazing product lead wrote those pages!!).