{"id":6963,"date":"2026-03-26T03:13:02","date_gmt":"2026-03-26T03:13:02","guid":{"rendered":"https:\/\/le-creator.com\/?p=6963"},"modified":"2026-03-26T05:56:04","modified_gmt":"2026-03-26T05:56:04","slug":"solving-surface-finish-problems-in-pom-machining","status":"publish","type":"post","link":"https:\/\/le-creator.com\/es\/blog\/solving-surface-finish-problems-in-pom-machining\/","title":{"rendered":"Resoluci\u00f3n de problemas de acabado superficial en mecanizado POM"},"content":{"rendered":"
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How to Solve Surface Finish Problems When Machining POM (Acetal\/Delrin)<\/strong><\/p>\n

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Quick Specs<\/h3>\n\n\n\n\n\n\n\n\n
As-Machined Ra (Standard)<\/td>\nRa 1.6\u20133.2 \u03bcm (63\u2013125 \u03bcin)<\/td>\n<\/tr>\n
As-Machined Ra (Optimized)<\/td>\nRa 0.4\u20130.8 \u03bcm (16\u201332 \u03bcin)<\/td>\n<\/tr>\n
POM Melting Point<\/td>\nPOM-H: 178 \u00b0C (352 \u00b0F) \/ POM-C: 166 \u00b0C (330 \u00b0F)<\/td>\n<\/tr>\n
Recommended Cutting Speed<\/td>\n120\u2013150 m\/min roughing, up to 450 m\/min finishing<\/td>\n<\/tr>\n
Typical Tolerance<\/td>\n\u00b10.05 mm standard, \u00b10.025 mm optimized<\/td>\n<\/tr>\n
Post-Finish Options<\/td>\nPolishing (Ra 0.2 \u03bcm), Bead Blast (Ra 1.6 \u03bcm), Vapor Polish (Ra 0.4 \u03bcm)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

POM (polyoxymethylene) is one of the most commonly used engineering thermoplastics for precision machining – when surface finish goes wrong. Machined POM components that should be Ra 0.8 m come back at Ra 3.2 m or worse, with shining drag lines, whisker-like burrs and scratches, or tool marks visible to the naked eye \u2014 and that rougher surface disqualifies these cnc machined parts from assembly. Root causes are POM-specific and physics-focused, and the solutions differ inherently from metal machining operations.<\/p>\n

This paper explains why CNC machined polyoxymethylene<\/a> surface finish is disastrous, how to identify a defect, what cutting parameters and tooling will fix each one. Each Ra value and feed\/speed recommendation is based on hard data and shop experience \u2014 not guesstimates. Whether you use CNC machining for POM homopolymer or copolymer POM, the principles are identical.<\/p>\n

Why POM Parts Come Out with Poor Surface Finish<\/h2>\n

\"Why<\/p>\n

Most failures of POM machining finish trace back to thermal conductivity. According to polyoxymethylene data on Wikipedia<\/a>, POM has a thermal conductivity of 0.31 W\/m K. Compare that to aluminum at 205 W\/m K – a 660x difference. When the machining operation wants to withdraw heat from the cutting zone, POM prefers to store heat in its workpiece instead.<\/p>\n

That heat capacity deficiency causes three kinds of roughness failure:<\/p>\n