One of the biggest limitations of FFF and SLA 3D printing is you can’t fabricate full-colour parts. You can only print mono parts, or parts in one colour. This is because in the case of fused filament fabrication, the printer extrudes a plastic from a reel. The reel is one colour, which means printed parts have to be too.
The way around this is to sand, smooth and paint parts. This post-processing is perfect for design studios and makers who have the time and expertise to detail parts, but not so good for everyone else. There is also a limitation with post-processing, and that is that even if you paint parts, the colour is only a top layer – it doesn’t permeate through the plastic itself, so underneath, it is still a solid colour.
Now, though, this limitation is a thing of the past.
HP is the innovator to thank, for they have developed a new 3D printing technology that enables you to print in full colour, or mono. The kicker is the technology can produce functional parts. So, as opposed to the full-colour paper parts made by the Mcor IRIS, those made by HP’s machine can be put to work.
Introducing the HP Jet Fusion 500 Series
The HP Multi Jet Fusion 500 Series is designed to automate the in-house production of functional prototypes and end-use parts. The 580 can print nylon in full-colour – a world-first for a desktop-sized 3D printer.
These 3D printers utilise a technology called Multi Jet Fusion, which has the potential to revolutionise your in-house workflow.
Multi Jet Fusion Technology
The technology, Multi Jet Fusion, also known as MJF, is proprietary. It utilises two perpendicular carriages to transform powdered plastic (Nylon 12) into solid parts. It fuses nylon and detailing agents together on the print bed, with infrared lamps which fuse layers in a single pass. This enables it to build highly complex parts.
Some people have compared MJF to SLA because of its capability, but the technologies differ greatly. For starters, SLA printers use resin, and whereas SLA uses a laser to scan and sinter each layer of printed resin, with parts then requiring curing with UV light, MJF uses an ink (fusing agent) which promotes the absorption of infrared light which occurs on the print bed with in-built infrared lamps.
MJF is, in fact, a faster 3D printing process than SLA, yet it can print parts with almost equal complexity and detail. Another benefit over SLA is no support material is needed, which means you can design parts without having to accommodate supports. This frees up design potential even further. Of course, SLA has its place and remains one of the best technologies for producing highly complex, detailed parts.
If you want to get technical, you could say MJF is a sort of mash-up between SLA and binder jetting. But while the technology shares similarities with both of these, it is standalone. There is nothing else quite like it on the market.
One of the key benefits of MJF is parts are self-supporting. This is because the underlying powder supports the part. However, a limitation is that you can’t print a sealed hollow model, because parts are solid (with powder). Therefore, if needed, drainage holes should be incorporated into designs. However, this is a small price to pay for the ability to 3D print unsupported models with overhangs.
The HP Multi Jet Fusion 500 Series consists of the HP Multi Jet Fusion 540, and the HP Multi Jet Fusion 580. Both 3D printers have Voxel Control, which enables you to control the physical properties of each voxel – or individual bits of powder – for enhanced control over part strength, appearance, and feature detail.
The ability to control individual voxels is quite a revolution in capability. Voxels are 25-micron blocks that enable true manual input over model characteristics, which brings new control over the printing process, by enabling designers to control more than just the surface of prints. Designers can control each voxel inside and out, which means you can go deep into the model to enhance quality.
No FFF, FDM or SLA 3D printers on the market have voxel control, so if you want full control over parts on the print bed, MJF is superior in that respect.
HP Jet Fusion 540
The HP Jet Fusion 540 prints consistent white parts, with voxel control so you can change the characteristics of parts at any point. Although this is not a full-colour 3D printer (that accolade goes to the HP Jet Fusion 580), the 540 is just as fast, just as capable, and has some seriously impressive specs to whet your appetite.
For example, you can print up to 100 functional parts a week, thanks to the 1,817 cm3 /hr (111 in3 /hr) build speed, which equates to a build job time for a 248-mm (9.8-in) part of 20-hours or a little less. The 540 prints high-quality parts every time, with no warping, and you do not have to incorporate any supports for parts.
The build volume is 332 x 190 x 248 mm (13.1 x 7.5 x 9.8 inches) which is plenty enough for most applications. It also automatically mixes fresh and reusable material and loads agents for you, to reduce waste and make your life easier.
HP Jet Fusion 580
The HP Jet Fusion 580 shares the same build volume and print speed as the 540, only this model prints in full colour. This is a huge upgrade, because it enables the production of inspection-ready parts and models, and perhaps even retail-ready ones. If you have ever wanted to print 3D models in full colour, this is the printer for you.
The full-colour 3D printing works like so: the Jet Head sweeps across the printed powder, depositing millions of drops of light-absorbing ink. These inks have different properties. Some are binding accelerators, others are colours. An infrared heater then sweeps across the bed. Some of the ink remains as full-colour powder, while ink-marked areas absorb the IR energy to sinter and fuse solid with the layer below.
Printed parts are self-supporting and the 580 is engineered to be capable of printing full-colour parts in a production run with repeatable results. You can quite simply finish a print, and press go on another to create two of the same models.
We are an authorised HP Partner and have tested Multi Jet Fusion technology extensively. If you have any questions, please feel free to contact us.
You can find out more about the HP Multi Jet Fusion series on the official HP website here. All images in this article are credited to HP.