Direct Slicing vs Adaptive Slicing

Slicing divides a 3D model into thin horizontal layers whose contours guide the deposition path.

• Direct slicing: the layers are cut directly from the original CAD model (without making an STL), so there is no triangulation error.
• Adaptive slicing: the layer thickness changes along the height of the part. Thin layers are used where curvature is high, and thick layers where walls are vertical.

Point	Direct slicing	Adaptive slicing
Input	CAD model directly	Usually STL (or CAD)
Layer thickness	Usually uniform	Variable by geometry
Main benefit	Removes STL approximation error, smaller files	Balances accuracy and build time
Staircase effect	Reduced by accurate contours	Reduced where it matters
Build time	Not directly reduced	Reduced (thick layers on flat sections)
Complexity	Needs CAD-specific software	More complex algorithm
Use	High-accuracy parts	Curved parts, time-critical builds

Exam tip

Mention staircase effect and that adaptive slicing trades accuracy against build time.