{"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\/pt\/secondary-machining-molded-plastic-gears\/","title":{"rendered":"Secondary Machining of Molded Plastic Gears"},"content":{"rendered":"
\n

Engineering context<\/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
\n

What the drawing needs to communicate<\/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

Inclua essas informa\u00e7\u00f5es no desenho controlado, na especifica\u00e7\u00e3o ou no anexo da solicita\u00e7\u00e3o de cota\u00e7\u00e3o, sempre que poss\u00edvel. Mant\u00ea-las fora de conversas informais facilita a compara\u00e7\u00e3o entre fornecedores e revis\u00f5es posteriores.<\/p>\n<\/section>\n

\n

Risk review<\/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
\n

Sample acceptance<\/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
\n

From design review to 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

\n

An\u00e1lise pr\u00e1tica do projeto para esta decis\u00e3o.<\/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

Registre as premissas no desenho ou na solicita\u00e7\u00e3o de cota\u00e7\u00e3o para que o fornecedor possa confirm\u00e1-las antes de enviar a proposta. Quando um valor for desconhecido, identifique-o como um item de engenharia aberto, em vez de copiar um n\u00famero de cat\u00e1logo gen\u00e9rico que pode n\u00e3o corresponder \u00e0 montagem.<\/p>\n<\/section>\n

\n

Folha de verifica\u00e7\u00e3o<\/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

    Utilize a primeira amostra para concluir esses pontos com evid\u00eancias dimensionais e a verifica\u00e7\u00e3o funcional relevante. Qualquer desvio aceit\u00e1vel deve ser registrado na revis\u00e3o controlada antes da produ\u00e7\u00e3o de nova amostra.<\/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\/pt\/wp-json\/wp\/v2\/posts\/1363","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/comments?post=1363"}],"version-history":[{"count":2,"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/posts\/1363\/revisions"}],"predecessor-version":[{"id":1608,"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/posts\/1363\/revisions\/1608"}],"wp:attachment":[{"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/media?parent=1363"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/categories?post=1363"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/injection-molded-parts.com\/pt\/wp-json\/wp\/v2\/tags?post=1363"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}