Shot Size Calculator
Calculate barrel capacity needed from part weight, runner volume, number of cavities, and cushion percentage.
Inputs
g
g
%
Results
Required Shot Size
170.5 g
Total Part Weight140 g
Shot Weight (no cushion)155 g
Shot Volume (approx)162.38 cm³
Min Barrel Capacity213.13 g
Ideal Barrel Capacity341 g
Runner Percentage9.7%
Max Barrel Capacity852.5
Barrel Utilization50%
How to Use This Calculator
- Enter part weight (g), number of cavities, and estimated runner/sprue weight (g).
- Set cushion percentage (typically 10–15% of barrel capacity) to maintain pack pressure.
- Review required shot size with cushion, total shot weight, shot volume (cc), and minimum barrel capacity.
- Select an injection molding machine whose barrel capacity is 30–80% of your shot size for optimal plasticizing.
Ad Placeholder
Related Calculators
Clamp Force Calculator
Calculate required clamping tonnage from projected part area, cavity pressure, and number of cavities.
Cycle Time Calculator
Calculate total injection molding cycle time from fill, pack/hold, cooling, and mold open/close phases.
Part Cost Calculator
Calculate per-part injection molding cost from material, machine time, and amortized mold cost.
Ad Placeholder