Input variables
| Variable | Meaning | Unit |
|---|---|---|
| x | Outer width | mm |
| y | Outer depth | mm |
| z | Outer height | mm |
| t | Wall thickness | mm |
| rho | Liquid resin density | g/mL |
Equations
Solid bounding-box volume · mL
outer = x*y*z/1000
Ideal internal volume · mL
inside = max(0,x-2*t)*max(0,y-2*t)*max(0,z-2*t)/1000
Ideal closed shell · mL
shell = outer-inside
Shell resin estimate · g
mass = shell*rho
Notation
PI means π. ** means a power, sqrt means square root, and abs gives the absolute value. Trigonometric functions use radians. min and max select the smallest or largest argument.
ceil rounds upward, floor rounds downward, and round rounds to the nearest integer with halves toward positive infinity. roundup(value, step) rounds upward to the next multiple of the step; a zero step leaves the value unchanged.
Assumptions
- This is a rectangular shell estimate, not an STL wall-thickness checker or a slicer replacement.
- Actual models have openings, internal supports and geometry that a bounding box cannot capture.
- Drainage and cleaning requirements must be checked in the model and resin instructions.
- Use the slicer’s supported model estimate for a final material order.
Precision and verification
The tool uses ordinary double-precision numeric arithmetic. Output is displayed to at most four decimal places; measurement precision is usually much lower. Check the worked examples, your project’s specifications, and a real sample before committing material.