Tuesday, 21 June 2016

Top 5 3D Printing Misconceptions

Given the roller coaster of attitudes towards 3D printing in recent years, it can feel like there is a plethora of misinformation on the technology. Misinformation has led to misguidance, misuse and ultimately distrust. To fully embrace 3D printing in all its varied forms, and therefore achieve the greatest overall value from what could be a crucial project solution, we’ve gathered some of the most common misconceptions we’ve heard from newcomers and industry veterans alike and addressed where the misconception comes from and how 3D printing breaks the mold.

Misconception 1: 3D printing can’t produce real functional parts. This misconception stems from early realities for the technology. In the first decade or so, 3D printed plastics were mostly relegated to photocure materials which were not durable. Most 3D printing processes did not have good tolerances or automation in place to aid in controlling the build to achieve a specific need. By about 2000, however, 3D printing was already maturing into full blown production use in aerospace and transportation. Today, 3D printing has significantly improved in material availability – with FAR rated, HST certified and biocompatible materials. In addition, process controls through automation and improved technology have transformed 3D printing into a reliable production solution.                                                                                                             
Misconception 2: 3D printing is slow OR 3D printing is instant (like Star Trek). This misconception is more involved with a confusion surrounding 3D printing in general. 3D printing is not one technology; rather it involves technologies with separate materials and processes. 3D printing refers to any process which involves additively building up or forming parts in layers. The speed for each 3D printing process depends on many factors including layer thickness, process, part size, geometry, and even material. A small prototype can take 1.5 hours with a technology like PolyJet or 5 hours with a process like laser sintering. However, there is no instant replicator technology like the one seen in Star Trek (which we suspect is somehow warping time).                                                                                                                  
Misconception 3: A 3D printed part is ready for use right off the machine. We certainly wish this was true, but 3D printed parts require post-processing to remove supports and support material residue along with other treatment processes depending on the technology and desired aesthetics or strength. Even laser sintered parts, which are support free, will undergo a simple air blast to remove loose powder. Support material is any material added to a part during printing that supports the part as it builds. It can be a separate specially formulated material or the same material as the final build material. Support material and support requirements greatly vary between 3D printing technologies.

Misconception 4: All 3D printing technologies require supports. While most 3D printing technologies do require supports, laser sintering is a zero-supports process. Additionally, designs can be oriented or reconfigured to reduce the amount of supports required for any 3D printing technology, including PolyJet, Stereolithography and Fused Deposition Modeling (FDM). It is helpful to understand why a process requires supports to appreciate how supports are added to a design.
  • Why a part requires supports: While a part is printing, the material may still be in a “green” state. A green material hasn’t completed its curing or hardening process. While it cures, hardens or otherwise completes its production, it usually requires supports to ensure delicate features remain accurate, or to avoid warping or similar problems.
  • The exceptions: Laser sintering builds in a bed of powder; the unsintered powder supports designs as they complete their melting and hardening process. However, metal laser sintering, which also builds in a bed of powder, requires supports. Metal laser sintering, or DMLS, heats designs at a significantly higher temperature than plastic, and once the metal is formed into a shape, it becomes much denser than the surrounding powder. Therefore without supports, the metal part would sink through the less dense, unsintered powder.
When designing for 3D printing, it’s important to take into account how your desired material or process utilizes supports and to talk to your project engineer about how supports can be used to supplement your design and achieve optimum products.

Misconception 5: 3D printing is expensive. All 3D printing technologies involve highly advanced manufacturing processes with a lot of intense hardware – lasers, noble gases, specially formulated materials – plus it requires human touch labor for build preparation and post-processing. In many ways 3D printing is like typical manufacturing with typical production costs. However, where 3D printing differs from conventional production and saves money is in the execution of complicated geometry without increasing time or labor. A complex, involved geometry is easy for 3D printing and doesn’t require the labor and manufacturing costs of a process like machining or tooling. If a part is large and simple, it probably won’t save you too much on your bottom line to produce with 3D printing. But a small to large part with involved details, interior features, and complex uses will see huge cost savings with 3D printing compared to conventional manufacturing. 

In the ever-changing, fast-paced ecosystem surrounding 3D printing, it can feel like the technology lurches forward at ever accelerating paces in just the blink of an eye. Learn more about 3D printing technologies and how they differ in “Find the Right Technology for Your Application”.

Today 3D printing is transforming manufacturing for aerospace, medical, energy, and many other industries with the expansive capabilities it currently offers. As 3D printing continues to evolve, who knows what tomorrow will bring!

Source: Stratasys Direct Manufacturing Blog