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.

WATCH: How Draft Makes Your Drink Cold

We’re kicking off an animated series that takes a quirky look at the fundamentals of molding. The first short video is on draft, one of the most important consideration during injection molding part design.

Check it out:

 
For more information on designing with draft, read our recent tip on 5 ways to improve part moldability with draft.

5 Ways to Improve Part Moldability with Draft

When designing parts for plastic injection molding, applying draft (or a taper) to the faces of the part is critical to improving the moldability of your part. Without it, parts run the risk of poor cosmetic finishes, and may bend, break or warp due to molding stresses caused by the plastic cooling.

Equally important, an absence of draft may prevent parts from ejecting from the mold, damaging not only the parts, but possibly the mold itself — a costly and time-consuming detour.

Chevron arrows indicate surfaces that require draft in Proto Labs’ design for manufacturability (DFM) analysis.

In this month’s design tip, learn how to improve the moldability of your plastic parts by:

  • drafting early and often
  • sticking to the rules of draft
  • factoring in surface finish
  • implementing the core-cavity approach
  • leveraging design for manufacturability analysis

READ FULL DESIGN TIP

TIPS WITH TONY: Mixing It Up with Plastic Colorants

Proto Labs’ material selection and available color options for thermoplastics can be found online at protolabs.com.

You may require colored resin or transparent coloring for your injection-molded parts, but exactly how much colorant is added and what consistency can you achieve?

Salt-and-Pepper Mix
Proto Labs offers colorant at no charge to most natural, white or clear materials. In most cases, we do this by adding a 3 percent salt-and-pepper mixture of colorant based on weight to the base resin, but on occasion, less colorant is added to transparent resins like polycarbonate.

A 3 percent salt-and-pepper colorant mix is typically used.

 

Since we hand mix the colorant and base resin, you may have a higher or lower concentrate of colorant throughout the order. The injection molding press does a good job of mixing the colorant and base resin when it melts and grinds the resin in the barrel before molding, but it isn’t 100 percent.

Continue reading