Steam Bending Calculator (beta)

Steam Bending Calculator — Inkleind
01

The bend you want

The inside of the curve. Measure from form's center to the workpiece's inner face.
How far the bend curves. 90° is a quarter-circle. Chair-back bows are 120–180°.
02

Your stock

Measured perpendicular to the bend plane. Thinner stock bends tighter.
For reference — doesn't affect math, but width > 4× thickness can twist.
Green or air-dried bends best. Kiln-dried needs longer steaming and may break more.
03

Your setup

A metal strap with end blocks puts the bend in compression instead of tension. Allows much tighter radii.
Holding the bent piece on (or in) a form until it dries to ambient locks the shape. Releasing early lets the wood spring further as it dries.
Your Plan —

Data based on USDA Forest Products Laboratory research (Stevens & Turner, FPL Agricultural Handbook 125 and FPL-GTR-113, public domain), Lee Valley / Veritas bending guides, and Lost Art Press chairmaking literature. Spring-back values are typical averages — variation from tree to tree, grain orientation, and bending technique can easily double or halve these numbers. Treat the output as a strong starting point, not a guarantee. Test a sample piece before committing to a critical bend.

View all