Injection Mold Design Guide -

: Use ribs for strength instead of thick sections. Rib thickness should typically be of the main wall thickness to avoid sink marks.

Used primarily in three-plate or hot runner molds; leaves a tiny dot vestige on top of the part.

: Keep maximum rib height below 3x the nominal wall thickness to avoid filling and venting issues.

Located on the parting line, these are easy to machine and modify but leave a visible witness mark that requires manual trimming. injection mold design guide

Always place the gate at the thickest section of the part. This allows the material to flow from thick to thin areas, preventing voids and sinking. Never place a gate near areas subject to high mechanical stress. 4. Cooling System Engineering

The feed system channels molten polymer from the machine nozzle into the mold cavities cleanly, rapidly, and at uniform pressure. Sprue Design

You never want to cut steel for a flawed design. Modern mold design relies on (Autodesk Moldflow, Moldex3D). : Use ribs for strength instead of thick sections

If you are an engineer tasked with designing a mold, follow this sequence:

Any like internal threads or side holes

Corrosion-resistant against corrosive gasses; mirror finish. 3. The Feed System: Sprues, Runners, and Gates : Keep maximum rib height below 3x the

: Contains the negative cosmetic geometry of the part. This side usually remains fixed during the cycle.

Driven by angled pins, these blocks slide outward perpendicular to the mold opening direction as the mold opens, freeing external undercuts.

Draft angles are sloped surfaces that allow the cured plastic part to eject smoothly from the mold core and cavity without scraping or dragging.