Why DFM matters before tooling
A DFM review helps identify molding risks before steel cutting starts. For custom injection molds, small changes to wall thickness, rib structure, draft angle or gate position can reduce short shots, sink marks, deformation and later mold modifications.
Wall thickness and material flow
The first check is whether the wall thickness is suitable for the selected plastic material and product size. Very thick areas may create sink marks and long cooling time, while very thin areas may need higher injection pressure and better flow balance.
Draft angle and release direction
A molded part needs enough draft for stable release from the cavity and core. The mold maker should review visible surfaces, ribs, side holes, undercuts and textured areas before confirming the mold structure.
Gate, runner and ejection planning
Gate location affects weld lines, filling pressure, appearance and part strength. Ejection layout affects deformation and surface marks. These points should be discussed together instead of treated as separate details.
What to send for DFM feedback
Send 3D drawings, 2D tolerances, material requirements, visible surface notes, assembly requirements and expected production quantity. If the design is still early, clear photos and size targets can still support an initial review.