About Tony Holtz

Tony is a technical specialist at Proto Labs with more than 10 years of experience ranging from CNC mill operator to mold designer to customer service engineer. While his formal education is in industrial machinery operations, he has extensive knowledge and experience in both traditional and advanced manufacturing processes and materials. Throughout his tenure at Proto Labs, Tony has worked with countless designers, engineers and product developers to improve the manufacturability of their parts.

On-Demand Webinar: Choosing the Right Rapid Manufacturing Method

We recently hosted a 30-minute webinar on: Choosing the Right Rapid Manufacturing Method for Plastic Parts. If you missed it, no worries. You can still watch it on-demand HERE.

What did you miss?
We discussed the benefits of rapid manufacturing for plastic components and how to select the correct manufacturing process:

  • 3D printing, machining and molding processes and specifications
  • Material selection and properties for each process
  • Advanced molding materials like thermally conductive plastic and liquid silicone rubber

Top 3 Questions Asked
How long will you keep a mold and do you inform the customer if you’re going to get rid of it?
We’ll store the mold for one year from the last order unless it is requested to keep in storage, and we’ll notify the customer of inactivity to if they would like the mold disposed of or retained in storage.

Is there any limit on volume for injection-molded parts?
No, you can get injection-molded parts in quantities of 25 to 10,000+ with several molds even surpassing 100,000 parts. We have the ability for single and multi-cavity molds dependent on size and complexity.

Can Proto Labs be used for light pipe assemblies in PC, PMMA and silicone?
Yes, we have molded countless parts in those materials for light pipe assemblies. Mold finish should be polished to a SPI-A2 with special attention made to the mold build for ejector pin location, gate location and parting lines.

Stay Tuned
Look for additional technical webinars throughout the year on various 3D printing, CNC machining or injection molding topics. The next webinar will discus how to navigate through Proto Labs’ design for manufacturability (DFM) feedback.

TIPS WITH TONY: 3D Printing Living Hinges

Did you know that living hinges are possible with 3D printing? Here are a few things areas to keep in mind when designing hinge functions so your part’s functionality and integrity remain intact.

Process
We offer two processes for 3D printing thermoplastic or thermoplastic-like materials: selective laser sintering (SLS) and stereolithography (SL). But only SLS will produce parts with the functionality required for a living hinge.

An SLS part with living hinge functionality.

Material
Anytime we see the potential for a living hinge in a 3D-printed part, we will strongly guide you to SLS. SLS uses nylon thermoplastic, primarily PA 850 Black, which is a nylon 11 material. PA 850 has an increased EB of 14-51% followed by ALM PA 650 with an EB of 24%.

However, you can’t take a part that was produced in PA 850 or ALM PA 650 and expect it to function as a living hinge without a secondary process first. When you have a living hinge, we need to know what direction or the range of motion in which the hinge may function. This is critical as we anneal the part by heating it to 250-275°F and flex the hinge in the intended range of motion. This extends the life of the living hinge by stretching the material instead of fracturing the links of resin.

SL offers thermoplastic-like materials, but they are not be recommended for living hinge applications. Somos 9120 is our most flexible material of all SL resins with an elongation at break (EB) of 15-25%.

Continue reading

TIPS WITH TONY: Replace Metal with Plastic to Save Weight, Cost

To decrease weight and potentially cost, you can replace metal with plastic on certain parts through 3D printing and injection molding. At Proto Labs, we use industrial 3D printing process stereolithography (SL) to produce thermoplastic-like parts that have a nickel coating on the surface. This offers the increased strength of aluminum die-cast components, without the weight. With injection molding, the introduction of thermally conductive plastics has broken new ground when looking for heat dissipation of expensive heat sinks.

Stereolithography parts built with SLArmor have a metal coating applied over a thermoplastic-like base.

SLArmor involves a ceramic-filled DSM Somos material, which has a metal coating applied to achieve the look, feel and, most importantly, comparable strength of aluminum without added weight. SL is a cost-effective prototyping method for initial parts that mimic metal before moving to higher volumes of die-casted parts.

The material properties of SLArmor are greatly improved in regards to heat deflection, tensile strength, elongation at break and elasticity. The chart below shows exactly how the material relates to die-cast aluminum in three different thicknesses that can be applied based on geometry of SL parts. Note that the thickness of the nickel plating may vary on each part due to the ability to apply the coatings.

Continue reading

Strategies in Light Underway in California

The big lighting and optics show, Strategies in Light, starts today in Santa Clara, California. We’ll be talking with designers and engineers over the next three days about how industrial 3D printing, machining and injection molding processes can help them develop well-designed, more efficient products and devices. Track us down at booth #102.

One topic that is certain to dominate the conversation is the relatively new thermoset material, optical liquid silicone rubber (LSR), which has many advantages during lighting development versus plastics like polycarbonate and acrylic.

Optical liquid silicone rubber prototype from automotive company MagWerks LED.

Optical LSR is changing the lighting industry with its superior material and optical properties that improve:

  • durability
  • lightweighting
  • heat resistance
  • UV stability
  • light transmission
In addition to ongoing optical LSR discussions in the booth, we’re co-hosting a presentation with Dow Corning on prototyping with optical moldable silicone on Wednesday, March 2 at 1 p.m. in the presentation theater. Proto Labs’ global segmentation manager Jeff Schipper and Dow Corning senior application engineer John Nelson will cover why optical LSR works well for prototyping and low-volume injection molding and the results of recent research on implementing aluminum versus steel tooling when molding with optical silicone.
We hope to see you at the show!

TIPS WITH TONY: High-Temperature Thermoplastics

We offer two high-temperature thermoplastics: PEEK and PEI. Both high-performance materials can be machined and injection molded, and produce parts that can withstand extreme temperatures.

PEEK
PEEK parts contain excellent mechanical and chemical resistance during high-temperature applications. Its mechanical properties consist of tensile modulus strengths of 90-200 MPa and a melting temperature of 662˚F (343˚C). Some grades of PEEK have operating temperatures around 482˚F (250˚C).

Because of its robustness, PEEK is commonly used in applications for mechanical and medical instruments. PEEK is also used widely in the aerospace, automotive and chemical industries due to the insulating properties and creep resistance of any dimensional changes in high-temperature applications.

PEI
Like PEEK, PEI (often called by its trade name Ultem) offers outstanding elevated thermal resistance, high strength, stiffness and chemical resistance. PEI consists of tensile modulus strengths of 96-190 MPa and with a melting temperature above 420˚F.

PEI is available in transparent and opaque colors including glass additives for improved mechanical properties. Unlike other thermoplastics, PEI provides optimal strength and resists stress cracking when the material is exposed to hydrocarbons, alcohols and acids that makes them ideal for automotive and aerospace applications.

Which Manufacturing Process is Best?
If you’re in need of small quantities (up to 200) of PEEK and PEI parts, we can machined them in less than 3 days. For increased quantities in the thousands, rapid injection molding can produce parts in 15 days or less.

The physical properties vary little between processes, so please test out one sample using machining before moving to injection molding if you are unsure if your parts design is complete or not.

Contact us if you have any further questions about high-temp plastics and specific questions regarding PEEK or PEI. We have a full staff of customer service engineers who can be reached at customerservice@protolabs.com or 877-479-3680.