• Our Company

Who We Are

M&R Engineering, a commercial and aerospace machine shop, offers over 40 years of experience delivering high precision CNC machined parts and high-quality screw machined components.  We are a highly respected contract manufacturer with over 100 satisfied clients across various industries.  We have AS9100 Rev D and ISO 9001 certifications, DDTC registration and we are also ITAR compliant.   As a result, we meet the requirements of our aerospace and military customers.  In 2007 M&R Engineering purchased R&B Plastics.   Therefore, which now expanding our manufacturing capabilities to commercial and aerospace machined plastic parts.

Our skilled team of engineers and machinists use the latest programming techniques and equipment to deliver high precision CNC Lathe, CNC Swiss, and CNC Mill commercial and aerospace machine shop components. We handle small volume large variety projects.   In addition, we also have many large volume projects requiring millions of pieces in annual demand.

We strive to be an extension of our customers’ supply chain.   We offer custom packaging, inventory management programs, barcoding, vendor-managed inventory, just-in-time, and dock-to-stock programs.  Our commitment to excellence is a commitment to you.

Our Facility

Located in a completely renovated 32,000 square foot facility in the city of Orange in Orange County, California, M&R Engineering delivers to customer expectations in a variety of aerospace and commercial industries. Our commitment to quality and improvement is uncompromised as we continuously invest in the most modern and efficient equipment possible. We are AS9100 and ISO 9001 certified, DDTC registered and ITAR compliant.

Our Team Our highly qualified team, with years of manufacturing and supply chain experience, is here to solve your toughest machining challenges.

Natalia Sephton President and CEO

Natalia acquired M&R Engineering in August 2018.  She initially joined the company in 2016 as Vice-President and Chief Operating Officer. Prior to joining M&R Engineering, she managed Torrance Operations for Alcoa Fastening Systems (Arconic Fastening Systems).  Natalia worked for Alcoa for 14 years and held multiple roles in engineering and operations with progressive growth in responsibility. Natalia received an undergraduate degree in Industrial and Systems Engineering and an MBA from the University of Southern California.  Natalia always puts the customer first and looks for ways to improve overall customer experience.

Maureen Derseweh General Manager

Maureen joined M&R Engineering in 1997 and has made a continuing contribution to various aspects of the business including sales, order management, inventory and production control, MRP implementation, and integration of R&B Plastics into M&R Engineering. Prior to M&R Engineering, Maureen was a plant manager for a company producing emergency notification products. Growing up in a manufacturing environment, Maureen has always had a passion for manufacturing products. She believes in putting the customer first, maintaining communications with customers on a daily basis and focusing on customer requirements.

Elizabeth Fierro Customer Relationship Manager

Elizabeth joined M&R Engineering in 2015 as an Office Manager responsible for Customer Service, Accounts Receivable, Accounts Payable, and Human Resources.  In 2020, Elizabeth got promoted to Business Relationship Manager where she is responsible for the overall customer experience.  Before M&R Engineering, Elizabeth was an Office Manager in Warehousing Industry for over 15 years. Elizabeth believes that Customer Satisfaction is our top priority. She believes in building strong, long-lasting relationships with customers to satisfy customers’ ever-evolving needs. 



Frank Musacchio Director of Manufacturing

Frank joined M&R Engineering as a Director of Manufacturing in 2016. Frank brings over 30 years of experience in manufacturing, heat treating and plating, lean manufacturing, supply chain management, MRP implementation, and project management. Frank held progressive management roles with a large aerospace manufacturer including production planning manager, manufacturing manager, and operations manager. Frank successfully developed and built operational teams that delivered higher quality and improved delivery to multiple product lines.

Kevin Tiedt Quality and Process Improvement Manager

Kevin joined M&R Engineering in 2005. Through the years, Kevin has had multiple responsibilities with the company, from running the shop operations to integrating R&B Plastics into M&R Engineering. Kevin brings over 30 years of machining experience. Currently, Kevin leads the Quality and Process Improvement team implementing advanced technologies throughout machining to deliver superior value to our customers. He is also heading M&R Engineering tech training team to ensure our employees are the best trained in the industry.

Are you ready to get your project started?Request a Quote

M&R Engineering believes that a successful business is built on dedicated employees. We are always hiring. Check out the Careers page for a complete list of open positions.

  • Mill Experienced Set Up Operator

    The CNC Mill Machine Set up operator responsible for Brother and Fadal Mill Centers for metal components with tight tolerances in a job shop environme...


    The Davenport Set-Operator is responsible for set up and running two machines in a high pace environment. The position requires the individual to be a...