No really, I did not believe it at first either. Proto-Pasta has done it again with another crazy filament! They have officially created and began selling a stainless steel and plastic composite that can be used successfully in FDM 3D printers. Obviously, I had to get my hands on it and give it a try.
Once I received my 500g spool, the first thing I noticed is that Proto-Pasta has created a 100% recyclable spool out of heavy duty cardboard. This is great! It is really nice to see companies like this thinking more about the big picture. So I loaded the filament up in our Ultimaker Original Plus and began the test print robot. On the spool it said to set the heated bed temp to 50c, but a heated bed was not required. So, I went ahead and followed directions and set the heated bed accordingly.
The filament was flowing very nicely at about 220-225c at a layer height of 120 microns. It printed just like any other PLA. Unfortunately, half way through the first print, the robot dislodged from the heated glass bed and I had to stop the print. The reason this happened was because the heated bed was not hot enough to hold tight to the part. I cranked the heated bed up to 70c where I like to keep it for PLA and started again.
The second print finished great! It held tight to the heated glass platform and printed very nicely. This stuff is definitely heavy and feels like a cast metal part. This material is obviously not as strong as metal, but it does give the appearance and feel of cast metal.
My final thoughts on the filament are that it is definitely a neat material for people looking to make things like sculptures, but I think this could be very useful to create parts that need to be heavy and have low impact requirements. This material is also pretty expensive at the moment, but I can see this coming down in price as the technology matures.