Delrin cost is directly related to the tool size, pass count, and setups. Here are the considerations for designing Delrin parts affordably.

Keep Radii ≥ Standard Tool Sizes

Use 2mm, 3mm & 5mm tool diameters wherever you can. A 1mm tool cutter will produce a 1mm wall. The tool will create very shallow step-downs (typically 0.5–1 mm/passage) when working in deep pockets. As such, your pass counts will rise.

Use Near-Final Stock

Start from a plate or rod close to the final size. Removing a large excess of plastic still adds time and chip handling without benefit.

Avoid Very Thin Unsupported Sections

Walls below ~1–1.5 mm over tall heights need light passes and extra checks. Add temporary support ribs if possible, then remove in a final pass.

Limit Depth-to-Diameter on Small Tools

When using smaller tools, keep your pocket depths within 3 times the tool diameter. At that point, you begin to lose step, and your cycle time begins to go up. If you are restricted in terms of pocket depth, then you should expand the pocket width so as to allow a larger tool.

Widen Narrow Slots Slightly

Narrow slots with dimensions equal to the tool diameter typically run at full engagement. You must keep the feed rate at a minimal rate. By increasing the slot size by roughly ten to twenty percent, you can enable partial engagement, which will give you increased speeds.

Keep Walls Consistent

Large differences in wall thickness force additional finishing operations. Maintain consistent wall thicknesses so you can use the same cutting parameters throughout the entire feature.

Finishes And Post-Processing Options For Delrin Parts

Delrin parts can be put into application directly from machining; additional operations may be completed depending upon how the part will interact with its surroundings (i.e., fit, motion) or appear within the final assembly.

The purpose of these operations is to enhance the interaction/operation characteristics of the part and not to change the basic part geometry.

Deburring And Edge Conditioning

Machining creates sharp edges, which are deburred and cleaned off. This process removes sharp points and debris at edge locations, and allows better handling by eliminating potential small interference issues during part assembly.

Deburring is typically performed on all Delrin components that require manual handling or fitting of parts together, as well as parts requiring assembly.

Surface Smoothing For Contact Areas

Contact surfaces are polished/smoothed to reduce friction characteristics. Smooth contact surfaces provide uniform operation in guide ways, slot ways, and mating surfaces.

In addition, surface smoothing is focused on contact surfaces only. Therefore, an attempt is made to keep machining marks to a minimum on surfaces that do not affect performance.

Polishing For Visible And Functional Surfaces

Polishing is used when surface finish affects both aesthetic quality and low-friction conditions. It improves surface feel and reduces minor machining marks in viewable areas.

Polishing is used on all exterior faces and visible component surfaces.

Laser Marking For Identification

Part numbers, batch numbers, etc., are laser-engraved onto Delrin parts. It produces clear, readable markings without altering dimensions or fit of parts.

Typically, laser engraving is performed during the last stage, after all machining and finishing operations have been completed. It is primarily used for identification purposes during the manufacturing of production parts.

Assembly Feature Preparation

Threads, holes, press-fit locations, etc., are inspected/cleaned before assembling. Cleaning removes any debris (e.g., machining residue) and burrs, which could cause mating parts to engage improperly.

Besides this, cleaning is necessary to avoid excessive force and improper alignment between mating parts during assembly.

Need CNC-Machined Delrin (POM) Parts?

If you have a Delrin part, Sochain Precision supports machining from prototype to production. We work on gears, bushings, housings, and sliding components with controlled cutting conditions.

Before machining starts, we review your CAD file to check tool entry, feature depth, and setup direction. This helps define how the part will be machined and avoids changes during production.

We run 3-axis, 4-axis, and 5-axis CNC machines to handle multi-face parts and complex geometry. For thin sections and press-fit areas, we apply staged cutting instead of heavy passes to maintain shape.

We also manage edge finishing, surface condition, and dimensional checks before delivery. This keeps parts ready for assembly without additional work.

Share your CAD file to get a quote. Our team reviews the design and provides feedback on the machining approach, cost, and lead time.