Buyer Guide
DFM Checklist for Plastic Injection Mold Tooling
Review wall thickness, draft, ribs, bosses, undercuts, gates, parting line, ejection, tolerance and cosmetic surfaces before tooling.
Why this matters
Review wall thickness, draft, ribs, bosses, undercuts, gates, parting line, ejection, tolerance and cosmetic surfaces before tooling. DFM review turns a CAD model into a moldable part by exposing wall, draft, rib, boss, undercut and tolerance issues early.
Buyer checks
Check wall-thickness transitions and sink-prone featuresReview draft angle against texture and ejection directionFlag undercuts that require sliders or liftersConfirm ribs, bosses and snap fits can fill and releaseMark cosmetic surfaces and unacceptable witness marks
Quote variables
| Quote variable | Why it changes the mold route |
|---|---|
| Wall thickness | Uneven walls raise sink, shrink and cycle-time risk. |
| Draft | Insufficient draft increases drag, ejection marks and polish risk. |
| Undercuts | Side actions add cost, wear points and schedule risk. |
| Tolerance | Tight tolerances may need steel-safe review, inspection and process control. |
Common mistakes
Treating DFM as a drawing formalitySending CAD without material or cosmetic requirementsSkipping assembly-fit surfaces and critical dimensions
How to apply it
Attach CAD, material, surface finish and problem areas, then request a DFM review before approving any tooling deposit. If the project is early, the guide can show whether the next move is CAD cleanup, DFM review, prototype tooling, production mold planning, export mold handoff or repair review.