A new breed of industrial extrusion 3D printers has started to appear on the market that brings the same or increased capabilities and material as professional machines at a fraction of the cost. Among them are the A2v2-3NA and A4v3-3NA 3D printers from the Italian company 3ntr, which have been brought to the United States courtesy of Plural Additive Manufacturing (Plural AM) in Lake Oswego, Oreg.
The A2 and A4 machines are fused filament fabrication (FFF) systems engineered to be able to 3D print industrial-grade thermoplastics, including a specially formulated blend of aerospace quality polyphenylene sulfide (PPS). A number of specialty features discussed in greater detail below allow these systems to reach temperatures as high as 410 C°. By being open to third-party materials, the 3ntr systems reduce the financial burden of owning an industrial printer that may require the use of proprietary filaments.
The NA versions of the A2 and A4 come standard with three liquid-cooled hotends. (Image courtesy of Plural AM.)
Other novel features include a liquid cooled printhead with three nozzles, which is standard on both North American (NA) versions of the machines. Most of these features can be credited to the chief inventor of the A2 and A4 3D printers, Davide Ardizzoia at 3ntr. The North American distributor, Plural AM, has introduced several more standard add-ons that contribute to the overall quality and usability of the machines.
A humidity controlled materials management cabinet will also be available in the second quarter of 2017, allowing up to six different materials to be preloaded in a controlled atmosphere, with any three materials able to be fed to the machine, and changed within minutes. Filament volume measuring will also be a part of this new material management system.
How the 3ntr Printers Work
The A2 and A4 printers' use of three extruders makes it possible to print with three materials in the same build, including soluble support for more complex geometries, such as objects with overhanging features or assemblies with moving parts. The liquid cooling on the extruders provides very precise temperature control over the hot ends. This feature, which is not available on the overwhelming majority of FFF printers, allows for greater quality control when it comes to extruding plastic.Due to the use of all-metal hot ends, which are capable of reaching 410 C°, the A2 and A4 can use a wide range of thermoplastics, including ASA, ABS, PC-ABS, PPS, HIPS, Nylon, Nylon-Carbon, self-lubricating iglide plastic, PETG, PLA, TPU, and 3ntr's soluble support material, dubbed SSU01. Some of these materials cannot be printed on standard desktop 3D printers but can be used for the production of end-use parts, and not just prototypes.
The A2 and A4 in Action
Plastic-Metals Technology, Inc (PMT) is an Oregon-based company that developed a unique metalizing technique for manufacturing electromagnetic interference (EMI) and radio frequency interference (RFI) shields. These shields are necessary for electronic devices in order to prevent crosstalk and interference between different parts of an assembly or from nearby devices.Rather than submerge an object in a liquid and applying an electric current to coat the object in metal, as occurs with electroplating, the firm's vacuum metallization process involves the use of a vacuum chamber. To apply a thin coat of metal to the surface of an object, the object is attached to a large rig and placed into a vacuum chamber. A piece of metal, such as nickel, copper, stainless steel or aluminum, is attached to electric coils on the rig and heated up to its boiling point, eventually becoming gaseous and coating the surface of the object.
To prevent any undesired areas from being metalized, PMT creates custom masks for these objects. And PMT doesn't just metalize one component at a time, but rather metalizes hundreds of parts at once on a rather large rig. For instance, PMT metalizes approximately 1,000 parts per day for a medical device manufacturer, using six rigs and 540 masks. For more complex objects, PMT has had to outsource the machining and printing of such masks, at a cost of about $30,000 per year.
To save time and costs, PMT purchased a 3ntr A2 3D printer, which is large enough to perform batch 3D printing of custom masks on demand. The company determined the precision of the system, as well as the price of the machine and the cost per part, to be perfect for its operations. Including the annual cost of the printer, its maintenance and the materials, PMT determined that the cost of 3D printing with the A2 is about 50 percent less than using a third-party machining/SLS printing supplier.
Tim Raugust, vice president and co-owner of PMT, said of the purchase, “We have always outsourced our fixture parts. Now that we are printing all of our fixture parts and prototypes in house, all design issues are mitigated immediately, resulting in faster fabrication of our fixtures. This allows us to produce production parts for our customer sooner.”
Manufacturer: 3ntr
Model: A2v2-3NA* and A4v3-3NA*
*North American–specific configuration
Material: ASA, ABS, PC-ABS, PPS, HIPS, Nylon, Nylon-Carbon, Nylon 66, Iglide (self-lubricating polymer), PETG, PLA, TPU, SSU01 (soluble support material), and most other materials designed for FFF 3D printing.
Build Envelope: A2: 24.4 in x 13.7[1] in x 19.2 in (610 mm x 350 mm x 500 mm); A4: 11.8 in x 7.9 in x 7.5[2] in (300 mm x 200 mm x 190 mm)
Layer Thickness: .00197 in (50 microns)
Printer Dimensions: A2: 37 in x 28.2 in x 44.3 in (940 mm x 715 mm x 1125 mm); A4: 20.7 in x 20.2 in x 24.2 in (528 mm x 515 mm x 615 mm)
Recommended Uses: 3D printing end-use parts from engineering-grade thermoplastics, as well as jigs, fixtures and prototypes
Machine Price: The A2v2-3NA: $45,000; the A4v3-3NA: $25,000
Who Should Use the A2 and/or A4:
The printers are well suited for those who need to batch manufacture low volumes of parts or produce tooling, jigs, fixtures and prototypes, but may not want the burden of the high costs associated with proprietary materials.[1] For 3-nozzle machines, subtract 1.38 in or 35 mm from the Y dimension.
[2] For 3-nozzle machines, subtract 1.54 in or 39 mm from the Y dimension.
Why You Wouldn't You Use the A2 and/or A4:
The A2 and A4 are not intended to be hobbyist machines, but rather industrial systems for manufacturing and prototyping operations. Therefore, they are not designed to fabricate tchotchkes or other items where dimensional accuracy and repeatability are not of prime importance.
Plural AM has sponsored ENGINEERING.com to write this article. It has provided no editorial input. All opinions are mine. —Michael Molitch-Hou