Offset shell v1.8.0

Grow every surface of an STL outward along its normal, confirm the result is watertight, and export it.

1Load a model

Choose an STL fileor drop it on the viewer — units are read as mm

No file handy? or

File units

×

Orientation (Z is up)

X

Y

Z

Step

Place on build plate: center on X/Y and set the bottom to Z = 0

2Set the offset

Method

Follow the mesh Volume-based

Measures distance to your model on a 3D grid and builds a new surface exactly that far out. Always clean; outside edges come out rounded, as a true offset does.

Offset distance (mm)

Corners and edges

Keep sharp Smooth normals

Faces move the full distance; edges and corners stay crisp.

Detail

Draft Standard Fine

Finer detail captures small features better and takes longer (Fine can take 20+ seconds).

Exported body

Solid offset Hollow skin

Only the added layer: offset surface outside, original surface inside with normals facing in.

Smoothing Off

Evens out ripples and facets on the offset surface. Higher amounts round off small details. No point moves more than 40% of the offset distance, the enclosed volume is preserved, and it never opens the surface or flips a face; the inner surface of a hollow skin is left exactly as the original.

3Check the result

4Export

Drop an STL file hereDrag to orbit, scroll to zoom, right‑drag to pan

Offset opacity 34%

Original Offset Folded faces