{"id":1363,"date":"2026-09-11T06:59:49","date_gmt":"2026-09-11T06:59:49","guid":{"rendered":"https:\/\/injection-molded-parts.com\/secondary-machining-molded-plastic-gears\/"},"modified":"2026-09-14T07:53:37","modified_gmt":"2026-09-14T07:53:37","slug":"secondary-machining-molded-plastic-gears","status":"publish","type":"post","link":"https:\/\/injection-molded-parts.com\/vi\/secondary-machining-molded-plastic-gears\/","title":{"rendered":"Secondary Machining of Molded Plastic Gears"},"content":{"rendered":"
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B\u1ed1i c\u1ea3nh k\u1ef9 thu\u1eadt<\/h2>\n

Secondary machining can refine bores, faces or datums after molding when the assembly needs a relationship that is difficult to hold directly from the tool.<\/p>\n

The benefit must be weighed against extra handling, fixturing and the possibility of releasing molded-in stress. Machining also changes the datum chain if the gear tooth form remains as molded.<\/p>\n

Secondary machining is most valuable when it controls a specific relationship that the molding process cannot hold economically. Typical candidates are precision bores, bearing seats or mounting faces. If the gear is fixtured from a cosmetic outer surface, however, machining may introduce a new eccentricity. The fixture should locate from a stable molded datum that has a known relationship to the teeth.<\/p>\n<\/section>\n

\"Secondary<\/figure>\n
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B\u1ee9c v\u1ebd c\u1ea7n truy\u1ec1n t\u1ea3i \u0111i\u1ec1u g\u00ec?<\/h2>\n

Identify exactly which feature is machined, which molded surface locates the part in the fixture and which dimensions are inspected afterward.<\/p>\n

H\u00e3y \u0111\u01b0a nh\u1eefng th\u00f4ng tin \u0111\u1ea7u v\u00e0o n\u00e0y v\u00e0o b\u1ea3n v\u1ebd \u0111\u01b0\u1ee3c ki\u1ec3m so\u00e1t, b\u1ea3n \u0111\u1eb7c t\u1ea3 k\u1ef9 thu\u1eadt ho\u1eb7c t\u00e0i li\u1ec7u \u0111\u00ednh k\u00e8m y\u00eau c\u1ea7u b\u00e1o gi\u00e1 (RFQ) n\u1ebfu c\u00f3 th\u1ec3. Vi\u1ec7c t\u00e1ch ch\u00fang ra kh\u1ecfi c\u00e1c cu\u1ed9c trao \u0111\u1ed5i kh\u00f4ng ch\u00ednh th\u1ee9c s\u1ebd gi\u00fap vi\u1ec7c so s\u00e1nh nh\u00e0 cung c\u1ea5p v\u00e0 ch\u1ec9nh s\u1eeda sau n\u00e0y d\u1ec5 qu\u1ea3n l\u00fd h\u01a1n.<\/p>\n<\/section>\n

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\u0110\u00e1nh gi\u00e1 r\u1ee7i ro<\/h2>\n

Adding a machined bore without a coherent tooth-to-bore datum can improve diameter size but not runout.<\/p>\n<\/section>\n

\"Secondary<\/figure>\n
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Ch\u1ea5p nh\u1eadn m\u1eabu<\/h2>\n

Use a fixture and inspection plan that references the functional gear datum structure.<\/p>\n

For Secondary Machining of Molded Plastic Gears, close the DFM loop by updating the controlled CAD\/drawing and sample plan. A recommendation that never reaches the released revision cannot be inspected consistently in production.<\/p>\n<\/section>\n

\"Secondary<\/figure>\n
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T\u1eeb kh\u00e2u xem x\u00e9t thi\u1ebft k\u1ebf \u0111\u1ebfn y\u00eau c\u1ea7u b\u00e1o gi\u00e1 (RFQ)<\/h2>\n

Before requesting a price for secondary machining of molded plastic gears, identify the current drawing revision, production quantity, material constraint and the feature that most strongly affects function. Ask the supplier to flag any deviation from those inputs in the quotation so technical alternatives stay visible.<\/p>\n<\/section>\n

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Practical design review for this decision<\/h2>\n

Secondary machining can improve a final bore, datum, face or thread, but it changes the process chain. Define the datum used to locate the molded part, expected stock allowance, clamping method and how the machined feature relates to the gear teeth or molded interface.<\/p>\n

Record the assumptions on the drawing or RFQ so the supplier can confirm them before quoting. When a value is unknown, identify it as an open engineering item rather than copying a generic catalogue number that may not match the assembly.<\/p>\n<\/section>\n

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Verification worksheet<\/h2>\n
    \n
  • Molded datum used for setup<\/li>\n
  • Stock allowance<\/li>\n
  • Machined feature tolerance<\/li>\n
  • Clamp distortion risk<\/li>\n
  • Burr \/ stress \/ surface requirement<\/li>\n
  • Final inspection after machining<\/li>\n<\/ul>\n

    Use the first sample to close these points with both dimensional evidence and the relevant functional check. Any accepted deviation should be captured in the controlled revision before repeat production.<\/p>\n<\/section>","protected":false},"excerpt":{"rendered":"

    Engineering context Secondary machining can refine bores, faces or datums after molding when the assembly needs a relationship that is difficult to hold directly from the tool. The benefit must be weighed against extra handling,…<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1363","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/posts\/1363","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/comments?post=1363"}],"version-history":[{"count":2,"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/posts\/1363\/revisions"}],"predecessor-version":[{"id":1608,"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/posts\/1363\/revisions\/1608"}],"wp:attachment":[{"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/media?parent=1363"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/categories?post=1363"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/injection-molded-parts.com\/vi\/wp-json\/wp\/v2\/tags?post=1363"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}