What thermoplastic is incredibly strong, rigid, low-friction, and dimensionally stable? We’re talking about acetal homopolymer—or, as it's better known, Delrin®. 

Machining Acetal: Acetal’s Brag-Worthy Properties

This 100% recyclable thermoplastic is an excellent choice for both moist and dry environments. It’s also stronger, offers lower water absorption, and presents a cleaner surface finish than UHMW and HDPE. Because acetal is creep-resistant, it’s easy to machine and fabricate, ensuring highly precise, repeatable results.

Some additional benefits of acetal include:

• Excellent mechanical stability

• Fatigue resistant

• Flexible

• Good electrical properties

• Resistant to fuels, hydrocarbons, neutral chemicals, and organic solvents

Numerous industries trust acetal for their parts. Common applications include:

• Automotive parts

• Electrical components

• Food processing parts

• Mechanical gears and valves

• Medical devices

• Packaging equipment components

A polymer replacement for aluminum and steel

Believe it or not, acetal is a viable substitute for aluminum or steel in many applications. Acetal’s low coefficient of friction against metals, other acetals, and plastics ensures exceptional performance, even in heavy-use scenarios. 

Machining acetal is easy, too—and the material doesn’t require the strengthening heat treatments we often recommend for metals and alloys.

Asking for Acetal vs. Delrin Machining Services

In the precision machining world, the terms “Delrin” and “acetal” are often used interchangeably. Customers will request Delrin machining services because they’re familiar with Dupont’s brand-name Delrin material when, in most cases, another acetal would work just as well for their part. (It’s the same way someone might ask for a Kleenex® when they really just need a tissue.) 

However, like many brand-name products, Delrin can be especially difficult and expensive to source. When customers call out Delrin specifically, we often contact them to obtain approval for acetal instead because it gives us more options for sourcing the material they need quickly and cost-effectively. 

When Delrin is the optimal choice for precision machining projects 

There are times when Delrin is the optimal choice over other acetals—like when a part needs to be exceptionally strong.

There are two types of acetal: homopolymer and copolymer. Delrin is an acetal homopolymer, the stiffest, strongest unreinforced polymer available. Unlike acetal copolymers, the homopolymer has “a uniform backbone with a larger crystalline block structure” that ensures superior chemical bonding.

If Delrin is truly the best material for your part, we’ll be sure to let you know. 

Get Acetal and Delrin Machining Services from Accurate CNC Services

Acetal is one of our favorite polymers to work with here at Accurate CNC. 

This simple-to-machine, wonderfully versatile, general-purpose engineering plastic performs beautifully in applications that require precision tolerances as tight as +/- 0.001”. We can even laser engrave your acetal parts with your part number. (Just ask!)

Want to discuss our acetal and Delrin machining services? Get in touch—or head straight to our RFQ portal and get a quote.