American Sycamore
Platanus occidentalis · hardwood · Eastern North America · moderate movement
- Janka hardness 770 lbfred oak ≈ 1,290 lbf
- Density ≈ 34 lb/ft³specific gravity 0.49 at 12% MC
- Shrinkage — tangential 8.4%flatsawn width, green → ovendry
- Shrinkage — radial 5%quartersawn width
- T/R ratio 1.7 : 1higher = more cupping in flatsawn stock
Shop notes Quartersawn sycamore’s lacework ray fleck is a hidden gem. Flatsawn it moves and weaves; quartersawn it behaves — saw it accordingly.
Seasonal movement at a glance
Width change for american sycamore across a typical indoor year — 6% moisture content in the heated winter to 12% in a humid summer:
| Board width | Flatsawn | Quartersawn |
|---|---|---|
| 6″ | 3/32″ (0.108″) | 1/16″ (0.064″) |
| 12″ | 7/32″ (0.216″) | 1/8″ (0.129″) |
| 24″ | 7/16″ (0.432″) | 1/4″ (0.257″) |
| 36″ | 21/32″ (0.648″) | 3/8″ (0.386″) |
Run your own numbers
Different width, different climate swing — the calculator below is preset to american sycamore:
Typical swings:
American Sycamore questions
How much does american sycamore move with the seasons?
A 12″-wide flatsawn american sycamore board moves about 7/32″ across a typical indoor swing from 6% to 12% moisture content; quartersawn, about 1/8″. Its tangential shrinkage is 8.4% and radial 5% (green to ovendry) — a moderate-movement wood.
How hard is american sycamore?
American Sycamore rates about 770 lbf on the Janka scale — softer than red oak but sturdy (red oak is roughly 1,290 lbf). Density runs about 34 lb/ft³ at indoor moisture levels.
Is american sycamore good for wide panels and tabletops?
Yes, with normal precautions: its 1.7:1 tangential-to-radial ratio is moderate. Still fasten solid tops so they can move across their width.
Similar species
Honduran Mahogany · Black Tupelo (Blackgum) · American Elm · Silver Maple · Black Ash · Bigleaf Maple
Shrinkage, specific gravity, and hardness from the Wood Handbook, FPL-GTR-282 (2021 edition), USDA Forest Products Laboratory (public domain). Values are species averages — individual boards vary with growth conditions and how they were dried.