3D metal printing is a niche within the 3D printing community owing to the expensive cost of the printing substrate and the much higher temperature needed to cure the print. Thus far, metal 3D printing brings the convenience of 3D printing complex made-to-order structures but is a very expensive and time-consuming process. However, that’s set to change with Desktop Metal’s (a Cambridge, MA based company) new metal 3D Printer – DM Production System.
Founded in 2013 by professors from the Massachusetts Institute of Technology, Desktop Metal has been in the news quite often. They’ve garnered the interest of a lot of investors who have been pouring money towards their 3D printers. Their 3D printers vary from others in the market by becoming more like the easily accessible consumer grade FDM (Fused Deposition Modelling) 3D printers rather than powder bed systems that are commonly used for metal 3D printing. They use an extrusion technique that binds the powder into a polymer matrix which is then extruded like an ordinary FDM 3D printer and is then cured by the furnace to produce the final product.
Desktop Metal Studio System and Production System
Desktop Metal has two metal 3D printers right now, there’s the affordable Studio System and then there’s the high output Production System which is claimed to be 100x faster than existing metal 3D printing systems. Desktop Metal says that the Studio System is 10x cheaper than existing metal 3D printers. How cheap? The entire system which comes with the DM Studio Printer, DM Debinder and DM Furnace along with a starter kit costs $120,000. That’s Rs.76,41,000. Not exactly cheap. Metal 3D printing systems from manufacturers like EOS cost somewhat the same but they’re mostly powder based systems. The Studio System is capable of printing at 16 cm3/hr with a layer height of 50 micrometres and the build area is 300 x 200 x 200 mm. This makes it very similar to current FDM 3D printers except for the resolution.
On the other hand, the Production System i.e. the newer, bigger and faster printer has a similar resolution but the build area is 330 mm in all dimensions and the print speed can go up to 8200 cm3/hr. That makes it 512x faster than the Studio System and 100x faster than competitive laser based systems.
Bringing about a 100x improvement in any system is a notable achievement. So let’s explore how Desktop Metal gets it done.
What makes the Production System 100x faster
Single Pass Jetting. That’s what Desktop Metal calls its technique of metal 3D printing that allows it to achieve higher volume and print speeds. Here’s how it works. The Production System has a print assembly which houses 16 print heads and two powder spreaders on either side of the print assembly. These components work in tandem within a single pass which in itself saves time and since the pass can be bi-directional, you deposit a new layer in each pass or twice per cycle. Each powder spreader deposits a layer of the power onto the bed which is metered based on the print job and then a compactor follows up to add rigidity to the newly added layer.
Then comes the print bar which houses 32,000 jets of which 16,000 jets are used for jetting the binder agent onto the newly deposited layer and then the remaining 16,000 jets are used to jet an anti-sintering agent onto the support section of the layer. This allows the supports to come off easily once the print comes out of the furnace. The anti-sintering step helps with reducing the amount of work needed in the post processing stage, an all too familiar stage that every FDM enthusiast comes across. The last component of the print head is the heating lamp which speeds up the layer drying process.
This forms one pass of the printing assembly in one direction over the print bed. As the printing assembly moves back over the print bed, the powder spreader on the other side of the print bar springs to action while the former stays dormant.
Everything else from this point onwards is the same as other powder based systems. A microwave based closed loop heating system heats the print to right under the melting point which removes the polymer binder from the print and fuses the metal particles together to form the solid print.
How much does the Desktop Metal Production System cost?
Frankly, we don’t know. Desktop Metal doesn’t have any pricing information about the Production System on their website aside from a reservation cost of $5,000. It’s likely to be very expensive given the high print speed. The claim that it is 10x cheaper stems from the fact that it can output a much higher quantity within a small time window. Printing the same quantity on existing systems will take more time and each print run will produce fewer prints. It’s when you compare the two systems on a per print basis that the 10x claim stands true.