Not wanting disappoint them right out of the gate, I threw out a standard rule of thumb used when pressed for max cycle counts: 250,000 is typically a good starting point, but can vary greatly—up or down—depending upon the following production characteristics and mold design:

Resin type, additives, required temp, corrosiveness, abrasiveness and flash rate

Residue type, powder, flakes, gummy (tar like) or oily consistency

Vent locations, depth and finish

Vent dump size, location and configuration (ring, channel, blind pockets, etc.)

Static vs. dynamic (moving tooling) vents

Tooling plating type and condition

Inaccessible internal bushing and other actuating components

Internal condensation level and mold plate steel type

O-rings and other internal water seal leakage history

Specific hot or cold runner issues
Another critical element when determining max cycle count is knowing part defect frequencies and positions that can be affected by many of the above criteria in specific areas. Mold and part defects localized by imbalanced fill or steel variations need to be recognized and considered when setting max counts. But generally speaking, anytime we overrun a mold, we increase the risk of molding bad parts, though burns, shorts, weld lines, dirty and flashed parts. Mold off-gassing—or residue—will end up someplace if it can’t escape through clean vents.