Last updated: 2026-09-02 · 5 min read

How Do You Plan Text and Logos on a Molded Part?

Plan molded text and logos backwards from the steel: raised features on the part are engraved into the mold and wear on its peaks, while recessed features are cut into steel that is easy to polish — so the first decisions are depth, draft on letter walls, placement on a face that ejects cleanly, and whether the mark belongs in the mold at all or on a separate plate. Get those four right at DFM and the logo survives a million shots; skip them and it fades by the second maintenance cycle.

Cavity — The hollow space inside the mold that forms the part shape. Multi-cavity molds produce multiple parts per shot. Cavity count determines production output but also mold cost and complexity. Each cavity must be balanced for uniform fill. See also related guide.

Key Facts

  • The direction rule: text raised on the part means steel removed from the mold (engraved), which is durable on the part but sits on protruding steel peaks that wear first and cannot be polished easily once worn. Text recessed on the part means steel standing proud in the mold — easy to cut on an insert, easy to polish, and replaceable as an insert.
  • Depth and draft travel together: 0.3 to 0.5 mm is a common depth range for raised text, with 10 to 15 degrees of draft on letter walls so the part releases without tearing the letters. Deep, straight-walled letters fill short, stick in the steel, and read as fuzz within weeks.
  • Legibility sets the floor: stroke width and letter height must respect the resin — thin crisp serif faces mold poorly on textured or filled resins, while simple sans-serif faces with generous stroke hold detail. If legal text must be tiny, a laser-marked or printed patch may beat molding it.

    • Cavity — The hollow space inside the mold that forms the part shape. Multi-cavity molds produce multiple parts per shot. Cavity count determines production output but also mold cost and complexity. Each cavity must be balanced for uniform fill. The related guide covers adjacent topics.

    The Four Decisions, in Order

    Decision Options Rule of Thumb
    Direction Raised on part / recessed on part Recessed for durability and mold maintenance; raised when the design demands tactility
    Depth and draft Shallow with strong draft / deep with minimal draft Shallow and drafted wins every time; depth feeds release, not looks
    Placement Ejector face / slide face / gate-adjacent face Away from ejector pins and gates; on faces the steel can and polish
    Carrier Direct in steel / separate insert / nameplate Insert for logos that may change; direct for stable, long-life marks

    Design Rules That Keep the Mark Readable

  • Generous draft on every letter wall — ten degrees or more — because molded text is a release problem before it is a graphic design problem.
  • Stroke width in proportion to height: thin decorative faces fill out and blur, especially on textured surfaces and filled resins.
  • A flat land around the logo on textured parts, so the texture does not eat the small features; texture breaking into letters is the classic read-failure.
  • Placement on the draw direction: logos on slide-formed faces need the slide seam planned away from the strokes, or the seam will cut through them.
  • Spacing from ejector pins and gates so packing marks, blush, and pin shadows never land inside the letters.
  • Artwork delivered as vector with depth and draft specified — a screenshot pasted into an email is not tooling input.

    • Insert Carriers: When the Logo Will Change

    Brand marks, regulatory symbols and region-specific text are the marks most likely to change over a tool’s life — and each change costs least when the text lives on a replaceable insert instead of being cut into a cavity block.
    The insert approach costs slightly more upfront: a pocket, an insert with the engraving, and a witness line to manage. It pays back the first time the logo updates, because the revision becomes an insert order with a short lead time instead of welding, blending and re-texturing a cavity. The same logic applies to date wheels, cavitation codes and other text that changes by design — those are inserts almost by definition.

    Frequently Asked Questions

    How small can molded text go?

    Practical floors sit around stroke widths of a fraction of a millimeter, and the real limit comes from the resin and surface: easy-flow resins on polished steel hold small detail; stiff or filled resins on textures blur it fast. Test the actual font, depth and material combination on a trial coupon before committing a program part — the datasheet will not answer this one.

    Why does my molded logo look fuzzy after a few months?

    Raised text sits on the highest steel points in the cavity, which see the most abrasion and are hardest to polish in place. Fuzz is wear plus shallow draft plus overpacking working together. The durable fixes are recessed text, insert carriers, and draft on letter walls — restoration is a bench project, prevention is a design decision.

    Should the logo be steel or paint or laser?

    Steel for marks that live forever and face abrasion; laser or print for variable data, tiny legal text, and anything that may be revised. Molding variable content into steel welds you to it — the costliest option for the one category of text that changes most.

    Key Takeaways

    1. Direction decides everything: raised text wears on steel peaks, recessed text polishes and lasts — choose recessed unless the design truly needs tactility.
    2. Shallow depth with strong draft keeps text moldable and legible; deep straight-walled letters fail at release before they fail at looks.
    3. Put changing text on inserts, keep logos clear of ejectors, gates and slide seams, and deliver vector artwork with depth and draft called out.

    Send the artwork with the drawing — vector, with intended depth, draft and face location — and aCatMould will return the mark plan in the DFM: direction, carrier, tolerances and the witness-line story for any insert, so the logo that ships is the one that still reads a million shots later.

    Sources
    MoldMaking Technology — engraving and text tooling practice
    Plastics Technology — part design detail guidance
    HASCO — insert and standard component systems

    Sources: Plastics Technology · Plastics Technology Online · Society of Plastics Engineers (SPE) · ThomasNet