Delrin and POM Machining for Gears, Bushings and Wear Parts
Send your drawing. We match it with shops that cut acetal every day and know how the material moves. Reply within 24 business hours.
Why buyers send Delrin work here
It comes down to the match: shops that fit your part, from the first quote.
Matched by specialisation
Your RFQ goes to up to 3 shops that machine acetal regularly, picked for your grade, stock form, part size and tolerance. Not a general directory.
Professional suppliers
Shops in the network quote to your drawing, communicate clearly and keep you updated while your parts are made.
You deal with the shop
Quotes, terms and delivery are agreed between you and the shop. Free for buyers.
Is Delrin the right material for your part?
Acetal is picked for a handful of reasons, and picked wrongly when nylon, PEEK or UHMW would do the job cheaper. Tick what applies to your part. Two or more ticks usually means POM is the right call.
Parts that usually end up in POM
- Spur and helical gears
- Bushings and plain bearings
- Cam followers and rollers
- Wear strips and guide rails
- Conveyor star wheels
- Valve seats and seals
- Insulating spacers and washers
- Small pump and metering parts
Acetal has a low coefficient of friction against steel and keeps its shape under load, which is why gear trains and bearing parts end up in it. It is not the answer above roughly 90 °C in continuous service, in strong acid, or under long unprotected UV exposure.
Homopolymer or copolymer?
Both are acetal and both machine in much the same way. The difference shows up in thick sections, in hot water and under repeated load. Naming the one you want on the drawing saves a round of questions.
Acetal homopolymer (Delrin)
Higher crystallinity, so it is stiffer, harder and holds up better under repeated load.
- Best choice for gears, cams and parts that flex in service
- Highest strength and wear resistance of the family
- Large diameter rod can have a less dense centre, so thick parts are roughed out and checked first
- Loses more in hot water and alkaline washdown
Acetal copolymer (POM-C)
Lower crystallinity and a more even structure right through the section.
- Better in hot water, steam and alkaline cleaning
- More uniform in thick plate and large rod
- Slightly lower strength and stiffness than homopolymer
- Common default for food and water contact parts
Grades and what to expect on tolerance
These are typical ranges from machining acetal, not promises. Thermal expansion for POM sits near 110 micrometres per metre per kelvin, roughly ten times steel, so the shop that quotes you confirms what it can hold on your geometry and at what temperature it inspects.
| Grade or form | What changes | Typical tolerance |
|---|---|---|
| Acetal homopolymer (Delrin) | The stiffest and hardest of the family, and the best under repeated load. Thick rod can carry a softer centre, so shops often rough it out and check before finishing. | ±0.05 mm general, ±0.025 mm on small features |
| Acetal copolymer (POM-C) | More uniform through the section and more forgiving in hot water and alkaline cleaning. Slightly lower strength and stiffness than homopolymer. | ±0.05 mm general, ±0.025 mm on small features |
| PTFE filled acetal | Lower friction and less stick slip for dry running bearings and slides. Costs more per kilo and is usually bought as rod. | ±0.05 mm is a safer target |
| Glass filled acetal (GF25) | Stiffer and moves less with temperature. It wears tooling faster and is more brittle at edges and thin walls. | ±0.05 mm general |
| Food contact grades | Sold with FDA or EU 10/2011 documentation, often in blue for detection. Ask for the compliance sheet with the quote, not after. | Same as the base grade |
| Sheet, rod or tube | Rod suits round parts and gears. Sheet suits plates and guides. Stock form changes price and lead time more than most buyers expect. | Stress in sheet can warp thin plates |
What tolerance a shop can actually hold in POM · All acetal grades compared
Where Delrin parts are used
Different industries bring different paperwork. Mention material certificates, food contact compliance or first article inspection in your RFQ so we match shops that already work that way.
Food and beverage
Star wheels, guides and wear parts in compliant grades that survive daily washdown.
Automation and conveying
Rollers, bushings, chain guides and bearing blocks that run dry.
Medical devices
Housings, cams and insulating parts in low volumes with full material traceability.
Automotive
Fuel system parts, clips and gear trains in small series and prototypes.
Electrical and electronics
Insulators, spacers and terminal blocks that hold dimensions and do not conduct.
Water and fluid handling
Valve seats, impellers and manifold blocks in contact with cold water.
How it works
One RFQ from you. A short list of shops that fit. No bidding platform and no middleman on the order.
Send your RFQ
Upload a STEP file or PDF drawing and tell us grade, quantity, tolerance and when you need it. Takes about three minutes.
We match up to 3 shops
We read the drawing and pick shops that cut acetal, hold the stock form you need and take your part size. You hear from us within 24 business hours.
Shops quote you directly
Each shop contacts you with a quote. You compare, ask questions and place the order with the one you choose.
What drives the price of a machined POM part
Six things decide most quotes. If a price looks high, one of these is usually the reason, and some of them you can change on the drawing.
- Setup and programmingCAM programming and workholding are paid once per order. On 1 to 10 pieces they are most of the price.
- Stock form and gradeRod, sheet and tube are priced differently. Filled and food contact grades cost more per kilo and are not always on the shelf.
- WorkholdingPOM is soft and springs under clamping. Soft jaws, vacuum plates or sacrificial fixtures add setup hours to thin parts.
- Tolerance and annealingA stress relief cycle between roughing and finishing adds a day or more, and it is what tight tolerances on thick parts usually need.
- QuantitySetup spreads over more parts as quantity rises, so price per part drops quickly past the first few dozen.
- Deburring and inspectionPOM holds a fine burr on sharp edges. Hand deburring, edge break notes and first article reports all add time.
Have a drawing ready?
Send the short version now. We will ask for anything missing. If you prefer to give full details up front, use the full RFQ form.
Your files go only to the shops we match. Ask for an NDA and nothing is shared until it is signed.
Machine engineering plastics? Get RFQs that fit your stock.
Shops see a preview of each request before paying for it and talk to the buyer directly. We take no commission on the order.
Questions buyers ask
Something else? Email .
Is this service free for buyers?
Yes. You pay nothing to send an RFQ or to receive quotes. Shops pay us for matched requests. Price, terms and delivery are agreed between you and the shop.
Do you machine the parts yourselves?
No. We are a matching service, not a machine shop. The shops that quote you own the machines and the bar stock, and you place the order with them.
Are Delrin, acetal and POM the same material?
POM is the polymer, polyoxymethylene. Acetal is the common name for it. Delrin is a brand of acetal homopolymer. Acetal copolymer is sold as Hostaform, Ultraform, Tecaform and others. Homopolymer and copolymer machine in much the same way but behave differently in hot water, in thick sections and under load.
What tolerance can a shop hold on a machined POM part?
Around ±0.05 mm is routine on general dimensions. ±0.025 mm is realistic on small features when the shop controls shop temperature, takes light finishing cuts and lets the part settle before inspection. Tighter than that needs a conversation about the specific feature, not a blanket note on the drawing.
Who sees my drawing?
Shops first see a short preview with part type, material, quantity and tolerance. It does not include your name, company or files. Your contact details and files go only to the shops we match, up to 3. If only one or two shops fit the part, we send it to fewer rather than fill the list. If you ask for an NDA, we hold the files until it is signed.
Which file formats can I send?
STEP or IGES for the 3D model, plus a PDF drawing with tolerances and finish notes. DWG and DXF also work. A STEP file together with a PDF drawing gets the most accurate quotes.
Guides for buyers of machined acetal
37 plain guides on grades, tolerances, design and what a quote is made of.
- Materials
Delrin vs Acetal Copolymer: Which POM Should You Specify
Homopolymer and copolymer acetal machine alike but differ in hot water, in thick sections and under load. How to choose one and write it on the drawing.
- Process
Delrin Machining Tolerances: What Shops Can Actually Hold
Acetal expands about ten times more than steel. What tolerance a shop can hold on machined POM, when a part needs annealing and how to tolerance the drawing.
- Cost
Delrin CNC Machining Cost: What Really Drives a Quote
Stock, setup, workholding, annealing and deburring decide what a machined POM part costs. How to read a quote and which changes lower it without redesign.