Metal printing differs from polymer printing in several respects:
– Most metals must be printed in an inert atmosphere. Argon is typically used, nitrogen can be used in some cases. Oxygen MUST be removed for some metals, such as titanium. The system contains an oxygen sensor and gas feed line. Once the cartridge is loaded, the inert gas flows into the production chamber & replaces the air. Once the O2 levels are well within the safety parameters, the printer will enable printing.
– Metals must be printed on a support base, usually of a similar metal to the build. This is supplied in the build cartridge. In most cases thin support structures can be used that will enable snapping off the part, but in some cases the part will need to be removed by cutting, such as with a band saw.
– Metal printing speeds are slower than polymer speeds. The high temperatures needed to melt metal require longer dwell times. Typical rates are 1/5-1/10 polymer speeds.