MULTI-JET FUSION

_{ENGINEERING-GRADE RESULTS AT ALL QUANTITIES}

There are many forms of 3D printing - but to be able to economically and reliably produce one to tens of thousands of parts in engineering grade material without detailed hand finishing then powder-bed fusion technologies are the obvious choice.

THE TECHNOLOGY

WHAT IS MULTI-JET FUSION?

Multi Jet Fusion (MJF) is an HP-patented technology that produces parts similar to the long-established Selective Laser sintering (SLS) technology.

Like SLS it works by adding sequential layers of polymer powder into a build chamber. In contrast to SLS, however, MJF uses a combination of a fusing agent jetted onto the powder surface and a high-powered heat source to selectively fuse areas of each layer together to form parts. Both SLS and MJF can produce high numbers of parts within a single block of powder without needing to incorporate support structures.

The main advantages of MJF over SLS are that the process is significantly faster and more efficient in terms of powder use. The parts also have more uniform mechanical properties and greater part detail thanks to the application of a detailing agent around the edge of parts.

Assessing alternative mediums

WHAT MATERIALS DOES MJF USE?

PA12 - Most common, good mechanical properties
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PA11 - Similar to PA12 but more sustainable, higher elongation at break, slightly easier to print with and better surface finish
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PA12 GB - Glass filled PA12, stiffer material with slightly lower strength
TPU M95A - high rebound and good abrasion resistance

While we may supply other materials, we focus on production in PA11. This material is highly versatile and appropriate for a wide range of use cases. It is also more environmentally friendly than other materials, being derived from Castor Oil. Our economies of scale and focus on efficiency allow us to offer this material at a competitive price even compared to the usually cheaper PA12.

VIBRO-POLISHING & DYEING

SURFACE FINISHES

VIBRO-POLISHING Out of the printer, parts have a slightly coarse surface. As an additional service, Bowman 3D offers vibro-polishing of parts - using ceramic beads to smooth the surface of parts over a number of hours.

DYEINGOut of the printer, parts are a neutral shade of gray. Parts can be dyed using black ink.
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*It is possible for parts to be both vibro-polished and dyed.

SPEC YOUR PARTS

TECHNICAL LIMITATIONS

TOLERANCES

The general tolerance for parts in PA11 is +/- 0.3mm or 0.3% (whichever is greater). Due to the additive production method, tolerances and material properties can be affected by the specific geometries of any given part. The reality is that for most smaller parts the tolerances achieved are significantly better than stated above – get in touch with us to discuss requirements and test print samples to get an idea of what is possible for your project.

DIMENSIONS

The largest part size in theory would be 380mm x 284mm x 380mm based on the size of the build unit. However, it is sometimes possible to exceed one of these dimensions by orientating the part appropriately in the build. We can also help to split large parts into smaller assemblies. Get in touch with us to discuss issues with dimensions.

PART ORIENTATION

Orientation within the build unit can impact on surface finish and consistency of dimensions. Unless specified by the customer, we will orientate parts to be built according to our own best practices as determined by our production team.

WARPING

In addition to general tolerances, thin unsupported parts have a tendency to warp – as parts cool following fusing, less dense parts tend to cool faster which can lead to distortion in parts. This can be reduced or eliminated by thickening parts and altering geometries.

One of our key manufacturing processes at Bowman 3D is HP 3D Printing's Multi Jet Fusion (MJF) technology. These #production3Dprinting machines are perfect for producing parts for a wide range of applications.

OUR STRENGTHS

Bowman 3D is a division of Bowman International, a leading innovator of bearings and components. Bowman International has three specialist divisions and one American subsidiary, all united in delivering our mission of genuine innovation, product performance and stock availability.

To read more about Bowman International, visit the Group website.