Lifetime Mold Guarantee | Xcentric | Since 1996

Lifetime Mold Guarantee | Xcentric | Since 1996

We often get asked about our Lifetime Mold Guarantee.  What is it?  How does it work?

Xcentric offers a Lifetime Mold Guarantee at no extra cost to you for the life of your project. We stand behind every mold we build and run.

plastic injection molding

Features and benefits of the Lifetime Mold Guarantee include:

  • No Part Quantity Limits – There are no part quantity limits for the life of your project.
  • High Quality Mold Components – We are committed to providing you with only the highest quality mold components.
  • Proactive Mold Maintenance – With our U.S. based tool room, we proactively maintain your mold. Each mold is serviced each time prior to and after running a project; saving you time and money.
  • All Parts Are Run on Electric Mold Machines – Our all-electric machines have the benefit of running at a higher speed and are more efficient throughout the entire production process. Independent motors and sensors control the process and prevent damage to the mold.
  • Our Propriety Process Engine is utilized to prevent part overshot and applying too much pressure in the cavity which can potentially break mold features.

For additional information regarding our Lifetime Mold Guarantee, contact one of our Technical Specialists today at 586-598-4636 or

Expanded CNC Capabilities

We have expanded our current CNC machining capabilities.  In order to precisely create your simple-to-complex parts, we offer the following:
  • Facilities with expanded 5-axis CNC machining centers
  • 3, 4 and 5 axis machines that save you time and money
  • Metal or plastic parts
  • A variety of surface finishes are available
  • Unlimited undercuts
  • Threads and holes
  • Our advanced processes give you competitive pricing and quick turnaround times
  • Parts up to 24” x 36” x 7”
  • ISO 9001: 2015, UL/ITAR
Would you like additional information on our CNC capabilities?  Contact our Technical Specialists today at 586-598-4636 or    
Draft Angles Can Improve Plastic Part Designs

Draft Angles Can Improve Plastic Part Designs

How Draft Can Help To Improve Plastic Injection-Molded Parts

Draft is an angle incorporated into your plastic part design to aid in the ejection process.

Optimize part designs early

Plastic parts should be designed with draft to prevent sticking and ejector pin push marks on the outward surface during ejection. Applying the proper draft angles or tapers on the surface of an injection molded part is critical to part moldability. Often times, draft is not considered when prototyping with CNC machining or 3D printing. It should be considered when either one of these prototypes will ultimately be injection molded. Not incorporating draft into your design upfront can directly result in costing more time and money later on in the manufacturing process.

Potential Pitfalls of Not Including Draft

Without draft being included in the design, parts may bend, have poor surface finishes, break, or warp due to stresses on the molded part. Which, if not dealth with can lead to sticking, breaking, surface finish imperfections and a variety of other issues causing manufacturing delays. In addition, the absence of draft may also damage the mold itself. You do not want your part to look like the photo below.

draft imperfections in injection molding

Proper planning can assist in avoiding costly mistakes.

Best Practices 

Although there is not one set draft angle for all plastic injection molded parts, below are some general guidelines:

• 0.5° on vertical applications
• 1.5° to 2° per side are standard for plastic injection molding
• 3° for light texture or shutoff (metal sliding on metal)
• 5° or more for a heavy texture

A good guideline is 1° of draft per 1” of cavity depth however keep in mind that a variety of factors will influence this such as material selection, wall thickness, shrink rates and manufacturing capabilities.

Draft best practices for injection molding

Do you questions or concerns about draft? Upload your design today at or let one of our Technical Experts assist you by contacting us a 586-598-4636 or email It is a good way of avoiding future moldability issues.

For additional information on draft, click draft.

Celling Biosciences Receives Complex Parts in 30 Days

Celling Biosciences Receives Complex Parts in 30 Days

Celling Biosciences Recieves Complex Plastic Parts in 30 Days

Medical and scientific devices pose three key challenges for companies like Celling Biosciences: time, quality, and cost. On one hand, to build a reputation for leadership in the closely watched biotech industry, you have to launch innovative products before your competitors can do likewise. On the other hand, if you can’t manufacture high-quality injection molding parts with complex geometries at market acceptable prices, you lose to those who can. Those were the concerns of Celling Biosciences’ engineering team in Austin, Texas when they sought for competitive bids to manufacture parts for a new clinical blood-therapy device.

Complex Geometries Are Difficult to Produce

In late 2017, Medical Design Engineer Jay Jones was issuing bid packages for this project. He had identified three competent parts manufacturers. Among them was  Xcentric Mold & Engineering. He first heard about Xcentric from a colleague: “You just have to try them,” he was told. And by late 2017, he had already used Xcentric on more than one occasion to successfully produce parts that incorporated increasing levels of design complexity. But now he had something that was very difficult produce. Celling Biosciences’ new blood-processor — called the Autologous Regenerative Therapies (ART) Two-Step Platelet Rich Plasma (PRP) device — had all the hallmarks of a serious production challenge.

Jay had reduced the number of components in the design from 23 to 8 but making some of these parts would not be easy. One mold was quite simple, producing the orange thumb wheel positioned on the top of the final product. The mold for the transparent base component, however, incorporated geometries requiring complex mold features such as threaded inserts, slides, and multiple hand loads — the stuff any engineer would acknowledge as a real test for an injection molded parts supplier. Accuracy, quality, and adherence to tight tolerances were absolutely necessary to create a final product that clinical labs would buy and rely on for day-to-day safe and reliable operation

Overnight Quote and Injection Molded Parts in 30 Days

The team at Celling Biosciences also understood the impact of launch dates on profitability.  Their existing parts suppliers would normally take from four to six weeks to develop a quote in response to a bid package. Although that kind of lead time is built into a typical product launch by medical device companies, it doesn’t help the bottom line, and nobody has to like it. Other suppliers would decline or request multiple concessions on complex designs. So after uploading their design files to three bidders, the team was astonished when Xcentric responded overnight with a bid and zero design change requests.

By comparison, one of the other two bidders responded in four weeks, and the last bid came in after six weeks had passed. So on the bid process alone, Xcentric had saved Celling Biosciences a significant amount of lead time. But that wasn’t the end of the story.

After conferring with his colleagues at Celling Biosciences, Jay accepted the bid from Xcentric Mold & Engineering. The contract called for the creation of aluminum molds and production of parts made from a PC/ABS blend. Expectations were for a low- to mid-volume production flow, around 3,000 parts per year.

celling bioscience

Figure 1. The ART Two-Step PRP

This was the first time that Celling Biosciences had awarded a product with such complex geometries to Xcentric Mold & Engineering, so Jay had the usual sense of anticipation about delivery of the final product. His previous experiences with Xcentric, however, had been excellent, and he was confident that they would be able to handle the complex geometries in the ART Two-Step PRP. But he was unprepared for the fast production turnaround. Xcentric delivered the “first shots” (the first production parts) to his office within 30 days — including delivery time! Jay put it into his own words: “I was holding the finished product only a week after the second bidder sent a quote and two weeks before the last bidder responded! It’s the kind of timetable nobody in the industry can match.”

Complex Geometries at the Right Price

Despite the complex geometries of Jay’s design, Xcentric had fulfilled its promise of a fast turnaround for customers:

“No matter the complexity of your design or the quantity of your order, Xcentric can deliver a wide variety of plastic and metal custom parts in as fast as 1-15 days.”

The final success factor was the low cost of the Xcentric bid. The company had delivered a complex, high-quality product at a lower cost than competing bidders, while maintaining the whole production chain in the United States. Taken as a whole, Xcentric helped Celling Biosciences bring a complex product much earlier to commercial stage and within budget.

If you are interested in receiving more information, contact us at or 586-598-4636.

For more information on injection molding, click injection molding .

Product Material Selection That Ensures High Quality Parts

Product Material Selection That Ensures High Quality Parts

Product Material Selection

There are many elements that influence the plastic injection molding manufacturing process. A key component to this process is the material used to create the part itself. There are numerous thermoplastic resin material options that are available for plastic injection molded parts. The content of these materials will directly affect part production. It will impact several critical factors in the manufacturing process such as strength, durability, cost of production and time to market.

When you are working with a manufacturing partner such as Xcentric Mold & Engineering, you should be aware of the material content of your product. Ask if and how the materials are mixed. The answer to that question may affect your part’s future production success. To ensure the highest quality standards such as ISO, Xcentric Mold & Engineering always uses 100% virgin materials on every job in the manufacturing process.

Color plastic pellets

Not all manufacturers are created equal. In some cases, old or previous used materials are reground and incorporated into the material mix. This can lead to many pitfalls in the process such as material contamination and defective parts. Being aware and reviewing the right material composition upfront will contribute to ensuring that you have successful part creation and production in the future.

If you are interested in receiving more information on part materials, contact us at or 586-598-4636.

For more information on materials, click materials.

Surface Finish Samples | Injection Molding | Free

Surface Finish Samples | Injection Molding | Free

Great Surface Finish – But How Will It Look On Your Plastic Part?

Request a FREE Surface Finish Sample Kit. Design for injection molding with confidence.

The surface finish of an injection-molded plastic part is critical. This is because it effects the outcome of your product going to market. Whether an internal or external part, the finish can range from a rough textured surface to a fine polish.  Sometimes, cosmetic treatments impact the outcome. Engineers and Product Designers determine the finish of plastic parts based on the materials used in the manufacturing process, the development or production stage, and end-use applications.

There are numerous thermoplastic resins available for plastic injection molding. Each material offers a variety of features such as durability, flexibility, and strength.  Xcentric offers a robust material selection. Therefore, there are many surface finish options for your custom plastic injection molded parts. Below is a list of our more popular finishes.


Mold Finishes
SPI* Standard Finish Finishing Method
A-2* High Glossy Finish Grade #6, 3000 Grit Diamond Buff
A-3* Normal Glossy Finish Grade #15, 1200 Grit Diamond Buff
B-2* Medium Semi Glossy Finish 400 Grit Paper
B-3* Normal Semi-Glossy Finish 320 Grit Paper
XT-1 Light Texture Light Bead Blast
XT-2 Heavy Texture Heavy Bead Blast
*SPI (Society of Plastic Industry) Standards


Our aluminum molds can be quickly produced. All texture and polish is directly applied to the mold itself and transferred to the parts themselves during the injection molding process.

Request a free 8-piece surface finish sample kit, now. To discuss material selection, or a current project, contact an Xcentric Application Engineer: or at