<img alt="" src="http://www.qlzn6i1l.com/121098.png" style="display:none;">


  • Precision Plastic Machining
  • Rapid Prototype Manufacturing
  • Material Selection Expertise
  • Application Development
Manufacturing Near Net Precision Plastic Parts at Roncelli Plastics


CNC Machining

Injection Molding

Die Cutting

Rapid Production Machining

3D Printing

Clean Room Assembly


Machining Precision Plastics for Defense Aerospace Space Medical Industry




Oil and Gas

Medical and Life Science

Precision Plastics Machining Plastic Composite Materials


Top Requested Materials Include:

  • PEEK


Click here for complete material selection list.

About Us

Since 1969, we've been a California based manufacturer specialized in Precision Plastic Rapid Prototype Manufacturing, CNC Machining, Injection Molding and Clean Room Assembly of thermoplastic and composite components, for critical applications supporting a wide range of industries.  Some of the applications include parts for commercial aircraft to medical instruments to electronic fixtures and test sockets. 

We understand your projects are ever growing in complexity and innovation, we manufacture  custom parts to our client's specifications, including re-engineering existing parts with our expert design and engineering team. 

We’ve been in business for 50 years and we work with corporations ranging from small start-ups to Fortune 100 organizations around the globe.  We're a complete plastics resource offering best in class solutions, operating from a 42,000 sq ft facility with temperature-controlled machining.

Our highly experienced staff of machinists, quality personnel, and supervisors are dedicated to delivering the best quality thermoplastics in the industry.  We're an AS9100D/ISO 9001 certified company who has enjoyed success over the years as a result of our commitment to quality, integrity, and excellence for every customer.

Best In Class Solutions

Expertise:                       Material Selection, Application Development and achieve tight tolerance requirements

Quality Assurance:         State-of-the-art inspection and test equipment

Standard Responsibility:  On-time-Delivery and Zero Defects

Our Reliability:               Established depth of expert suppliers 

Certifications:                 AS9100D, ISO 9001:2015, ISO 13485:2016, ISO 27001:2013, ITAR Registered

Production Automation:   - Use of Sawyer Cobots

                                    - Greater Emphasis on Inspection and Quality

                                    - Client Success Story:  We doubled production of client's product with same lead times; with the limitations of 11 hrs of machining time / doubled by automation to 22 hrs of production time via Cobots.  




Roncelli Plastics_Production Automation







Video Vault

View How Our Production Automation Works


Client Review: Aerospace

“Within these past 12 weeks: We finalized the design, finished/released drawings, surveyed vendors, chose vendors, cut PO’s, made changes along the way, received parts, assembled 1 unit, ran a handful of successful validation tests and wrote a final report; All completed by the deadline. I want to thank you (Roncelli Plastics) and your team for working with us to make this seemingly impossible task, a success."

- Lead R & D Engineer (2018) 

 Stay Up to Date on Roncelli Plastics News and Plastic Manufacturing Trends:
Roncelli Plastics LinkedIn
plastic manufacturing companies