Introduction to Rapid Prototyping (LOM, BJ & MJ)

This is Part 4 of the series. You can read Part 3 here or start at the beginning.

First and foremost, thank you for joining us and I hope you enjoy! I will be closing out the series with a 4^th and final installment about LOM, BJ, and MJ (laminated object manufacturing, binder jetting, and material jetting). These technologies are 3 of the 4 newest in the rapid prototyping industry.

LOM Rapid Prototyping

LOM rapid prototyping is definitely one of a kind in the rapid prototyping world. LOM printing utilizes sheet material stock, unlike any other rapid prototyping technology. The LOM process was commercialized in 1991 by Helisys, which was succeeded by Cubic Technologies after their shutdown in 2000¹. Considering that quite a few materials come in roll form, LOM rapid prototyping is inexpensive and also a fast printing technology. LOM printing is currently one of two technologies boasting the capability of full-color end result prototypes due to the ability to print with papers. MCor has implemented a particular process called SDL (selective deposition lamination), which uses standard ink-jet-like concepts in their paper capable 3D printers which allows for multicolor prototypes².

LOM Printer Major Component Schematic

LOM prints are created by laminating sheets of various materials together with adhesives and heated rollers operating under a specific load. LOM prints are built by bonding a series of consecutive layers of thin, pre-glued, sheet materials together. Regardless of the benefits, this rapid prototyping technology is not very popular. The limited material selection and waste of the sheet material are two major downsides. Although LOM rapid prototyping is able to utilize sheet metals, it still cannot compete with the strength equivalence presented by EBM or DMLS printing. To me, LOM has a special place in the abstract, demonstrative and conceptual arts and marketing sectors.

Water Jet, Binder Jet, and Material Jet Rapid Prototyping

And finally, the Jetting technologies have very similar naming conventions due to the “Jet” meaning, yet major differences in capabilities. Jetting is as simple as it sounds, meaning to throw or spurt out. Much like an older manufacturing technology, Water Jet machining, BJ (Binder Jetting) and MJ (Material Jetting), all disperse build material or a binding agent at high rates of speed. BJ is showing more long-term promise in the face of production equivalent end components than MJ, which is more suitable for rapid prototyping. That being said, MJ is the current, youngest rapid prototyping technology on the market. MJ was patented in 1999 by Objet, Ltd. under the name of Polyjet which was later acquired by Stratasys in 2012³. BJ, the big brother to MJ, was introduced back in 1993 by MIT (Massachusetts Institute of Technology) during a class project⁴. The technology was then acquired in 1995 by Z Corporation⁴ who was later bought by 3DSystems in 2012⁵.

BJ prints are created by binding layers of powdered materials together. A series of consecutive, super-thin, powered material layers are bound by proprietary agents being dispensed from jetting printer heads. BJ rapid prototyping offers a wide array of materials, some needing post-process heat treatments, curing, sintering, and/or infiltration of secondary materials to fill in porosity. Metal BJ rapid prototyping is probably the most promising material and version of the technology. BJ printing provides scalability within the modularity of the printing heads which can drastically reduce print times. The end components do not have a support structure to remove much SLS, SLM, and EBM and the waste is very minimal once again. BJ and MJ are widely recognized for the capability of printing with sand or silica and ceramic. The Jetting technologies open up a whole new portal for traditional casting and molding with the sand/silica options.

OBJet Eden 260V in Idle Mode

MJ is very similarly binding layers of material together like BJ, however, the printer head is dispensing build material, support material, and a binding agent. MJ prints are created by dispensing liquid material in consecutive, super-thin layers which are being cured by UV light almost instantly⁶. MJ is definitely more limited in material selection much like SLA, FDM, and DLP. Furthermore, only variations of waxes and photopolymers are available for use with MJ prototyping technology. However, it shares the scalability for faster run times like BJ but has the downside of support structure removal. Perhaps the only two benefits of MJ are the speed due to the jetting technology and the production scale machine costs, which are said to be the lowest of any printing technology.