Atlas Steam Engine powers Sturgeon's Mill

Here is a little information on how the mill is powered.

The main engine that powers the Joshua Hendy head rig is our Atlas Steam Engine. It was manufactured in Indianapolis, Indiana in the last part of the 19th century. It is a double acting steam engine, meaning it gets power on both ends of the stroke. Steam will push the piston to the left and then open an exhaust value, relieving pressure on that side. Steam then pushes the piston to the right completing the cycle and then beginning again.

The bore of the engine is 11 3/8" and has a stroke of 16". The fly ball governor lets the engine run to about 200 rpm. With the 135 lbs of steam from the boiler the engine will produce approx. 30 hp. The 72" drive pulley pulls a belt over a 24" pulley at the head rig which turns the saw blade at 600 rpm.

The Atlas engine came to Sturgeons Mill from the Fuller Mill in Occidental and was brought to this site when the mill was moved in 1923. The Atlas replaced the “long stroke steam boat engine that powered the mill in Coleman Valley.

There are three other engines being put to work in the mill.

Our Erie engine has a 6" bore and 12" stroke funning at about 400 rpm and powers our Klamath 4 saw edger. At the edger is a small engine called a Soule (Soo-Lay) powering the feed rollers pushing lumber through the saws. The Erie engine is a little under powered; Ralph was disappointed with its performance and referred to it as "Old Gutless".

Our last engine powers the trim saw. It is a small engine with a 5" bore and 7" stroke running about 400 rpm. When the mill was built in 1923, the engine was mounted on a redwood stump. The old stump not being as solid as it once was has been replaced by a concrete footing and a large timber securely mounted to it, but traces of the old stump can still be seen. All the steam needed to run the engine comes from our Atlas boiler. This boiler is fueled by diesel and with the price of fuel these days; it is our biggest operating expense at the mill.

Photos of the Atlas Steam Engine


The heart of the mill - 1850's Atlas Steam Engine


Another view of the Atlas Steam Engine


The original wood-fired boiler still remains, but unsafe to use.


Steam can be seen here billowing from the exhaust ports.

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Thank you!
For successful season.

A hearty thank you to all who visited the Mill during one of our steam-ups this past year!! We, the members of the "crew", look forward to these “productive” weekends when we see you, who enjoy steam-powered machinery in operation, come and enjoy the fruits of our labor of the year. We each have our reasons for enjoying this Restoration Project and they all come together when we get together on these great weekends.

The only thing we ask of you is to support this Restoration Project when and however you can and to pass on to your friends the information about this Mill and your enjoyment in observing its operation.

We are located at:

Sturgeon's Mill
2150 Green Hill Rd.
Sebastopol, CA 95472

Please view map for directions to Sturgeon's Mill.

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