I wanted to share a great eBook from HP on how educators can lead the way into the industry of tomorrow.  This eBook explores how 3D printing began, how it has evolved, and how it will change the culture of design, as well as the potential of 3D printing for higher education.  The principles outlined mirror many of our other blogs we have posted so make sure to check out the rest of our expert center to learn more.  I truly believe our students are the future for leveraging 3D print and we need to ensure they are learning and applying the technology for the implementing Industry 4.0.  We at MasterGraphics are always looking to support education so don’t hesitate to reach out to me directly with any questions or requests for support.  For now – download this eBook and enjoy.  

Kevin Carr
President
kevin.carr@mastergraphics.com
847-704-4025

The HP Multi Jet Fusion (MJF) printing process is similar to injection molding in a few ways. MJF and molding are both heat-based processes that melt raw plastic to form the final part shape. Because of this, there are similarities in how to properly design and prepare a part for each manufacturing process.

Just like injection molding, we want to control the heating and cooling in MJF printing to ensure good part quality. The MJF process uses a combination of lamps and thermal cameras to do this. By monitoring and controlling the heating/fusing and cooling process we can prevent or minimize defects like warpage.

Figure 1: HP MJF Printing Process

Warpage

Warpage is a possible defect in any polymer process that involves heat. Warpage is especially common in long, thin, flat parts. (aspect ratio greater than 10:1) When plastic cools from molten to solid, it contracts to take up less space. When one area of a large flat part cools before another area, it can “pull” the part towards it. With small compact parts (as opposed to long thin parts) it is much easier to control the cooling and prevent warpage.

For large, thin, flat parts, we recommend placing the parts parallel to the X-Y plane. This causes the part to melt and cool at a consistent rate. To further prevent warpage, align the length of the part in the Y-axis. The lamp carriage moves in the X-axis, so it will fuse the entire part at once when it move across. Along these same lines, try to avoid fast cooling if warpage is an issue. This allows the parts to naturally cool while they’re “held in place” by the surrounding powder.

Parts placed in the center of the build volume towards the bottom will be the least prone to warpage. This is because it will cool the most uniformly (from the outside in)

Figure 2: Avoid warpage by placing parts flat in the center-bottom of the build area

Design Changes

If that still doesn’t work, we have a few more options. One, we could print other parts, or even sacrificial parts, surrounding this large one. This, in effect, cages in the bigger part to hold the heat in and also slows down the cooling so it’s nice and uniform. Just like injection molding, we can’t let one area cool faster than another or it will warp. The other option is to add some ribs or supporting geometry to your part to prevent warping. Depending on your application this may or may not be possible. You can design in support bars to keep a part aligned while it cools, then snip the alignment bars off. This is similar to trimming the plastic from the gate in a molding process.

Material Considerations

PA11 will be most susceptible to warpage. If flatness is a major concern, we recommend using PA12 or PA12 with glass beads. If PA11 is necessary, use the Fast print mode. Regardless of which material is used, the HP MJF parts are usually flexible enough to easily be re-shaped or pushed into their final mounting position.

Keep these best practices in mind when designing and preparing your MJF prints, and you should be able to eliminate or at least minimize warpage in your parts.

As additive manufacturing technologies have advanced, 3D printed parts have moved decidedly outside the Research and Development arena and onto the production line. These pivotal processes are developing and producing concepts previously unattainable in the manufacturing world.

Entrepreneurs to Fortune 500 companies and large OEM’s have embraced the advanced enterprise of 3D printing to meet their tough performance standards and requirements. As companies have designed for additive manufacturing and utilized it as a compliment to traditional manufacturing, new applications have come to the scene and changed what’s possible.

There are four industries in particular where the amazing capabilities of additive manufacturing have transformed production:

1. Aerospace
Aerospace companies were some of the first to adopt additive manufacturing. Some of the toughest industry performance standards exist in this realm, requiring parts to hold up in harsh conditions. Engineers designing and manufacturing for commercial and military aerospace platforms need flight-worthy components made from high-performance materials.

Common applications include environmental control systems (ECS) ducting, custom cosmetic aircraft interior components, rocket engines components, combustor liners, tooling for composites, oil and fuel tanks and UAV components.

3D printing delivers complex, consolidated parts with high strength. Less material and consolidated designs result in overall weight reduction – one of the most important factors in manufacturing for aerospace.

The rapidly innovating medical industry is utilizing additive manufacturing solutions to deliver breakthroughs to doctors, patients and research institutions. Medical manufacturers are utilizing the wide range of high-strength and biocompatible 3D printing materials, from rigid to flexible and opaque to transparent, to customize designs like never before.

From functional prototypes and true-to-life anatomical models to surgical grade components, additive manufacturing is opening the door to unforeseen advancements for life-saving devices. Some applications shaking up the medical industry are orthopedic implant devices, dental devices, pre-surgery models from CT scans, custom saw and drill guides, enclosures and specialized instrumentation.

Success in the energy sector hinges on the ability to quickly develop tailored, mission-critical components that can withstand extreme conditions. Additive manufacturing’s advancements in producing efficient, on-demand, lightweight components and environmentally friendly materials provides answers for diverse requirements and field functions.

Some key applications that have emerged from the gas, oil and energy industries include rotors, stators, turbine nozzles, down-hole tool components and models, fluid/water flow analysis, flow meter parts, mud motor models, pressure gauge pieces, control-valve components and pump manifolds.

For designers, graphic artists and marketing teams, the time it takes to form an idea and deliver it to the market is everything. Part of that time is simulating the look and feel of the final product during design reviews to prove ideas to key stakeholders. Consumer product manufacturers have embraced 3D printing to help develop iterations and quickly adjust design.

3D printing is great for producing detailed consumer electronics early in the product development life cycle with realistic aesthetics and functionality. Sporting goods have benefited from early iterations delivered quickly and with fine details. Other successful applications include entertainment props and costumes, lightweight models and sets, and finely detailed architectural models.

As 3D printing technology advances in speed and build volume, more consumer products may turn to additive manufacturing for their large volume demands.

MasterGraphics Additive Manufacturing Engineer, Mark Blumreiter explains how the MJF works and how this technology is different from other similar 3D Printer technologies.

The final application we’ll look at for fiber reinforced 3d printed parts is robotic arm grippers. Any tool at the end of a robotic arm benefits from being lightweight because it requires less energy to move the arm. The grippers also need to be strong and stiff enough to handle the stresses involved with lifting, assembling, or machining the component. Depending on the part that’s being gripped, the grippers sometimes require unique geometry. For these reasons, 3D printed fiber reinforced are the perfect solution.

A U.S. based fittings and valves manufacturer fully embraced the Markforged 3D print technology in their shop. Their engineers used to spend days or weeks tooling up a robotic work cell with custom machined grippers and fittings. Now they can re-tool the robot grippers in less than 24 hours.

Another great example of reinforced 3D printed parts on the shop floor is end-of-arm vacuum tooling. When lightweight, flat parts need to be moved around and assembled, it’s common to use vacuum tooling to use air and suction parts to hold and move them. The image below shows a blue tube that is pulling air through the black tool. This creates the suction necessary to lift and move these lightweight parts.

There are a handful of properties these vacuum tools can require that 3D printing excels at. First, the tool should be lightweight because it is attached to the end of a robotic arm. Second the air suction needs to be routed through internal channels to provide suction at multiple locations. Finally, the tool needs to fit a unique contour of the part it’s picking up. Fiber reinforced 3D printed parts are the perfect solution for strong, stiff, lightweight, custom geometry vacuum tooling.

Keep in mind, these vacuum tools are typically only needed in very low quantities (1-10 parts) which is perfect for additive manufacturing. There’s no need to book time on a CNC mill and fixture an aluminum block for machining. This makes it much quicker to iterate new designs as well.

Using data from another Markforged case study, these numbers show the difference between aluminum and fiber reinforced vacuum tooling.

CMM fixtures are used to hold parts in place as they are being measured by a CMM. These measurements help ensure the manufacturing process is working as planned, and parts are meeting their dimensional specs. The traditional way parts are held in place for measurement is a combination of clamps, posts, and stops. But with composite reinforced 3D printed fixtures, we can create a lightweight, sturdy, more functional fixture suited precisely for your part.

The below graphic shows real data is from a Markforged case study regarding a US aerospace company.

The reason these time and cost savings could be realized in the first place was because the 3D printed CMM fixture actually worked. This can’t be said for all 3D printed parts. In fact, many other 3DP materials would not meet the strength and stiffness requirements while still providing the cost savings. The Markforged fiber reinforced Onyx parts also provided a non-marring surface for the aerospace components to sit in. This helped prevent the occasional scratched part.

Engineers at this aerospace company had been looking for ways to avoid bottlenecks like CMM fixtures. Once they discovered the fiber reinforced 3D printed parts as a functional, cost effective alternative, they haven’t looked back.

In the past few years, composite 3D printing has officially hit the main stage. Companies like Markforged, EnvisionTEC, Cosine, and 3Dynamics are looking beyond traditional plastic extrusion machine capabilities and incorporating new materials such as carbon fiber, Kevlar, fiberglass, and ceramics. Combining these traditional fiber and ceramic materials with a proven additive technology creates a reliable and cost effective way to 3D print strong, durable parts for the shop floor.

The primary applications for fiber reinforced 3D printed parts on the shop floor include fixtures, jigs, tooling, and grippers; all of which can benefit from complex geometry and lightweight designs. This is where additive manufacturing excels. Anyone who is familiar with 3D printers knows that complexity is free.

The freedom to explore new design choices and 3D print truly functional parts for the shop floor can be a big time and money saver. Let’s look at a real world examples, 

• 3D Printed CMM Fixtures
• 3D Printed End-of-Arm Vacuum Tooling
• 3D Printed Robotic Arm Grippers

Not only is HP changing Additive Manufacturing with their print technology but also in their approach to advance the utilization of 3D print within manufacturing.  HP has a unique perspective since they have built their reputation on top quality and innovative equipment and they are sharing their knowledge on how to leverage 3D print from design all the way to manufacturing.  This series is designed to help companies understand how they can move from prototyping to production using 3D print.  HP currently uses Additive Manufacturing to produce final use parts and have cost justified and proven out the economics.  It must also be noted, after I have attended a number of these sessions, the concepts and training provided are applicable to other 3D print technologies such as SLS and Carbon.  I assure you it’s truly a great educational session.  

Click the link below to watch this YouTube video on what DFAM is.

https://youtu.be/uBBxGiBI6qU

Some highlights of what you will learn:

• How and why HP decided to leverage MJF 3D printing technology to manufacture over 140 function parts used in each of our new MJF 500/300 series 3D printers vs. injection molding.
• How to identify and select the right applications for additive manufacturing across your product lifecycle.
• Training on the fundamentals of effective design for MJF.
• How the process works and design strategies for MJF process optimization.
• How the materials behave and what to consider when designing for each of them.
• The new design paradigms that are enabled by additive manufacturing and the required mindset change.
• How to design for value maximization (process and cost).
• Training on the fundamentals of effective design for MJF.
• Live Design for Additive Manufacturing (DfAM) demo and application examples to inspire you.

You are always welcome to stay after the scheduled presentations and discussions to consult with technical experts from HP 3D Printing on your own parts.   That could be the most valuable part of the session is the post conversation on your specific challenges and if 3D print makes sense to utilize. 

Feel free to reach out to me to find the next HP DFAM event in your area.

Jim Hill
3D Account Manager
3701 Algonquin Rd, Ste 780
Rolling Meadows, IL 60008
847.704.4029 Direct
800.873.7238 Toll-free
JIm.hill@mastergraphics.com
www.mastergraphics.com