When customers ask us to do the improbable

PEP Connecticut Plastics never anticipates that our customers will give us easy parts to manufacture. Learn more about how our engineers welcome the improbable.

Getting the best results: What you need to know about machining plastics

Machining plastics is more than a science, it’s an art. So how can you successfully navigate the process of producing high-quality components? Our new whitepaper will guide you though key considerations such as plastics material selection, material specifications, tolerancing, and surface finish. Download now: ‘Getting the best results: What you need to know about machining plastics’

Our Customers Value Us as a Quality Machine Shop

Quality Control Audits, done on-site by customers, are a welcomed opportunity for Connecticut Plastics to demonstrate the integrity of our manufacturing and quality systems.  Our manufacturing process is organized and structured to insure we can meet the requirements of our most discerning customers in the machined plastics market.  As an ISO 9001 certified company, we implement effective controls over our policies, processes and procedures, which are all backed by appropriate documentation.

Efficient Design: An Exercise in Machined Plastic Part Price Reduction

Often, customers approach us with a drawing of a plastic component and ask to have our engineers critique it before having the component quoted for price and delivery. On other occasions, a customer may not have time to have their print reviewed, or they are looking to be proactive in the design process. Let me outline some key features to include or not to include in your next project and show how they can save you time and money. Radii vs. Chamfers – Unless otherwise specified (UOS), we typically apply a light break edge or chamfer to nearly all external […]

Clear Machined Plastic Choices – Part One

Many applications benefit from using clear machined plastic parts to help view the process or improve aesthetics. In the amorphous plastics family, the design engineer can select from 6 commonly available materials: acrylic, polycarbonate, Polysulfone, Ultem, PVC and COC/COP. While clear in varying degrees, the materials are all sensitive to stress cracking. Stress risers with high mechanical forces should be avoided. In particular, poor machining can lead to stress cracks after several months. All machined plastic parts require post polishing to return them to the original clarity. Without polishing, the machined plastic part is more translucent than fully clear. Acrylic: […]

Facts About the Tensile Strength of Machined Plastic Materials

For designers of plastic parts for machining, a frequent concern is the tensile (pulling) strength of the plastic material. The engineer sees gains in lower weight and lower cost while giving up tensile strength with plastic components. Tensile strength is the capability of resisting a load for a given cross section measured in PSI. While ultimate tensile strength is often cited literature, it has limited value in the plastic fabrication world. Depending on the plastic softness, ultimate tensile can arrive after significant deformation. For softer plastic machined components, tensile strength at yield may be more applicable. Tensile strength at break […]

Temperature Resistance of Precision Plastic for Machining

It is common for an engineer to pick an engineered precision plastic for machining based on a quick review of tables of temperature resistance. An internet search will yield data on the commonly reported continuous service temperature in air. A natural breakpoint for grouping is to consider them in 100 deg F increments: 150 – 200F — Low temperature plastics (Acrylic, PVC, UHMW, LDPE, HDPE) 200 – 300 — Mid-grade general purpose plastics (Noryl, Delrin, PET, BPT, CPVC, PP) 300 – 400F — Amorphus high temperature plastics (PS, PES, PEI) 400 – 500F — High-performance plastics (PEEK, PPS, Teflon) 500+ […]

3D Printing: A New Technology That Took 30 Years to Perfect

3D printing is rapidly catching on and becoming the darling of manufacturing today. Manufacturers are turning to 3D printers to quickly produce prototypes for their customers. This very important step in any design process that used to take weeks to achieve can now be completed in a few days. Manufacturers are finding lots of other uses for 3D printers. Printing one-off parts and replacement parts makes it no longer necessary to maintain an inventory of old parts. This was the original concept of the 3D printer, however, as the process has been improved, more manufacturers are turning to 3D printing […]

Tolerances for Plastic Machined Parts

An often heard question when designing a plastic machined part is “What tolerance can you hold?” The answer to that is it depends on many factors including material choice, part configuration and the type of machining operation and technique. Generally speaking, plastics are not as stable as metals but with the right approach, surprisingly accurate parts can be produced. There are no hard rules but many guidelines that can help with the design. Here at Connecticut Plastics we are always interested in pushing the limits of plastic machined parts. If your product demands close tolerances for success, just ask. We […]

Dimensional Stability of a Machined Plastic Component

Dimensional stability of a machined plastic component is a frequent challenge. Maintaining accurate dimensions is a combination of part configuration, material choice, and machining technique. In general, a basic configuration with most plastics targeting +/- .005 tolerances is readily achievable. However this premise can readily fall apart simply through a single close tolerance dimension or an unstable configuration with a difficult material. Best option is to call a plastic machining job shop. Plastic machinists who have to make the part will always have a good opinion. Part Configuration As there are an infinite number of part configurations, this is a […]