⏳ Wood Drying Time Reference Chart

A general starting-point reference for air-drying green wood, based on the widely used rule of thumb of roughly 1 year of drying per inch of thickness for hardwoods in typical conditions. Actual time varies with species, climate, and whether the blank is rough-turned first.

Where the year-per-inch figure comes from

The chart runs on the old air-drying rule of thumb, applied straight:

years ≈ thickness in inches × 1

thickness = the shortest path moisture has to travel out,
            not the width or the diameter

That is the part people get wrong. A 12 in wide blank cut 4 in thick is a four-year wait, not a twelve-year one, and a 2 in blank sits at two years however wide the board it came from. It is a planning figure, not a measurement.

The three ways round the wait

Rough-turn first. Take the bowl down to a wall of about ten per cent of its diameter, an inch on a 10 in bowl, and the wait drops to weeks or a few months. It will move oval as it goes, which is why the piece is finish-turned afterwards.
Bag it. A paper bag holds damp air around the piece and slows the surface down so it does not shrink far ahead of the core, which is what splits a blank.
Buy it dry. Kiln-dried stock arrives at roughly 6-8 per cent moisture and needs no wait at all.

Species, airflow, sealed end grain and your own climate all move these figures, and a blank in a damp shed may never reach the moisture content of one indoors. The reliable test is a scale: weigh the blank every week or two, and it has stopped drying when the weight stops falling.

Frequently asked questions

How long does it take to air-dry a 4 inch bowl blank?

Around four years by the year-per-inch rule the chart uses. Rough-turning it to a one-inch wall first is what most turners do instead, which brings the wait down to months.

How do I know when a blank is actually dry?

Weigh it. Water is the only thing leaving, so a blank whose weight has held steady for a few weeks has stopped losing moisture. A pin meter reads the outer layer, which on a thick blank can be dry while the middle is not.

Can I turn green wood straight away?

Yes, and it cuts easily, but it will shrink and distort as it dries. That is fine for a rough-turned blank you intend to return to, and a problem for anything you want to stay round.