The standard gate at the parting line, feeding the edge of the part. Easy to machine and maintain and suits most geometries, but it leaves a visible mark and needs secondary trimming.
A widened edge gate that fans out before the cavity. It spreads melt across wide, flat or optical parts to reduce warpage, jetting and stress — at the cost of a larger area to trim.
Melt enters a small sacrificial tab first, then the part. This keeps gate stress and jetting off cosmetic surfaces; the tab is trimmed afterwards. Common for thin, transparent or high-stress parts.
A tiny round gate used in 3-plate molds. It breaks off and self-separates from the runner, leaving a very small mark and allowing central or multi-point gating. Needs higher injection pressure.
The gate tunnels below the parting line into the side of the part. It is self-degating — the part shears off the runner on ejection with no trimming — which suits automated, high-volume production.
A curved tunnel gate that reaches onto hidden or inner surfaces, keeping the gate mark off visible faces while staying self-degating. It needs careful design and a consumable insert.
The sprue feeds the cavity directly with no runner — ideal for single, large or deep-draw parts and strong flow. It leaves a large gate mark that must be machined and can add stress.
A heated nozzle keeps plastic molten right up to the gate, so there is no runner scrap. A hot tip leaves a small thermal gate; a valve gate uses a pin for a clean, mark-free, precisely timed gate. Higher tooling cost, best at high volume.