Making Lumber the Old Fashioned Way - a Windmill Sawmill

 

Lumber seasoning in water prior to milling into planks.

Wednesday, April 20, 2022

You could hear the working sawmill from a block away - Whoosh, whoosh, whoosh from the turning sails in the wind; whomp, whomp, whomp as the crankcase turned the gears to saw the log into planks.

The Het Jonge Schaap Sawmill (The Young Sheep) is a cap winder mill that was reconstructed in 2007 from a windmill demolished in 1942.  Cornelius Cornelisz from Uitgeest first discovered how to saw timber using wind power.  He used a crankshaft to drive framing saws.

To operate the mill, the cap with its four blades is turned by means of a winch to position the capstan wheel so that the blades are facing the direction of the wind. Once positioned, the capstan is anchored with a large chain. The rotating horizontal movement of the sails is converted to an up and down sawing movement through the crankshaft

Eight blades are being used with the framing saw to turn the huge log into planks

The volunteer points above to show Michael where the crankshaft is located

The frame saws move up and down, sawing about 1 mm for each movement.  A large iron ratchet wheel on the right pulls the carriage along with the loaded log.

The saw blades can be inserted at almost any width desired - at times 10 or 12 blades can be used in the frame - or as few as one or two.

The power of the wind drives these eight saws up and down, while the log is ratcheted forward

Friction from the sawing generates a great deal of heat - water cools and prevents sparking

Tree trunks are left lying in the water to season the wood before milling.  A pine trunk can be milled after soaking for 6 months. Hardwoods take between one and five years to remove the sugars and sap.  This makes it less prone to bending, warping and cracking when sawn.

A windlass, also attached to the windmill cranks, is used to pull the water laden trunks into the mill from the water.

Logs are soaked in water for 1 to 5 years to remove sugars and sap before milling

The windlass (black hook and chain on left) is used to haul the logs into the mill 

A ratched wheel is used to move the log forward as the saw frame cuts the planks

Fresh piles of planking cut today

The millworkers explained they have a busy "niche" market for their services.  When Napoleon conquered the Netherlands, he made them adopt the metric system, which is still in use for milling lumber today.

This mill has spacing for the non-metric measurements - and any house built before the 19th century needs these measurements for reburbishing or repairs.  When the winds are favorable, twenty logs could be sawed in a day.  There were usually 5 people staffing the mill from early morning until late evening.

I loved all the hand tools and the smell of the sawdust.  My father, lifelong carpenter, would have loved to see this production.

A wall full of non-metric spacers helps provide the measurement desired

Post mill air drying of the wood usually lasts about 6 months

The Young Sheep - Het Jonge Schaap mill

At its peak, there were 200 sawmills in the Zaan district

T