Protocol RL-202 // Polymerization Volumetric Contraction
Photopolymer Resin Shrinkage &
CAD Pre-Scale Calculator
Calculate monomer-to-polymer volumetric shrinkage (Sv = (Vmonomer - Vpolymer) / Vmonomer), differential green-state vs post-cure contraction, and exact CAD scale multipliers to achieve true dimensional accuracy.
1. Select Photopolymer Resin Formulation
2. Target Nominal Part Dimensions (Finished Part, mm)
Kinetic Mechanism:
Van der Waals forces between free monomers (distance ~0.35nm) convert to covalent polymer bonds (~0.15nm) during radical crosslinking, inducing macroscopic volume shrinkage.
Scale Compensation Dashboard
Standard Acrylate Slicer Offsets
Total Volumetric Contraction (Sv)Liquid Monomer to Solid Network
-7.6%Apply Slicer Scale Factors:
Scale X & Y102.20%+2.15% offset
Scale Z102.83%+2.75% offset
Compensated CAD X:81.76 mm
Compensated CAD Y:45.99 mm
Compensated CAD Z:25.71 mm
Linear Contraction Timeline:
Vat Printing (Green State):-1.40%
UV Cure Station (Final Cure):-0.75%