Industrial made micro windmill


The windmill is connected to the tower simply by pushing the thinner end of the tower inside it.

Tower (incomplete)

There's a plastic sheet inside the flagpole what must be taken away or pushed aside to get the elecricity cable through. Also it's good to make a mark to the tower where the rubber band is supposed to be tightened.

Base​ (incomplete)

Beams (incomplete)

The beams are not positioned correctly at the moment but the gap between the beams may be 2mm too thin for the flagpole so the wood may need slight chiseling. You can cut the ends of the beams diagonally against rain and paint the beams against rot. You can move the beams to better positions than they are left in.

Hinge and rubber band (incomplete)

You can paint the ungalvanised steel parts against rust.

Supporting structure inside the tank (undone)

The tank is only 5mm thick and because of the rust the bottom can be even thinner. It's possible to use bolts and/or welding in the sides of the tank to connect an as yet undesigned and undone supporting structure.

Straps (undone)

The straps connect the tower to the beams. You can make the straps simply from metal bands that you can screw to the beams. For extra durability and strength you can for example make the straps from pieces of thicker metal sheet that has holes for the screws.

Optional wheel for the rope

Rain cover (undone)

Since there are gaps around the tower and the beams of the base, a rain cover must be designed and made to prevent water flowing into the tank.


The windmill produces 3-phase AC. It's turned into DC by a 3-phase rectifier.

Automatic switch for the dump load (undone)

When the batteries are full, the electricity must be directed into a dump load by an automatic switch. So the windmill is always under a load and it can't free wheel and get damaged from the high spinning speed that can be reached in such a situation. The switch is placed between the charge controller and the mill.

Dump load (undone)

The maximum wattage the windmill can produce must be estimated using data from as yet undone voltage and amperage tests that can be done with a multimeter. The dump load can be made in several different ways. One easy way is to spin a right lenght of welding chord around a ceramic plate that has angle grinded grooves in the sides.

Steps to raise and lower the windmill


-tighten the rubber band around the tower so that a maximum portion of the tower is under the hinge while the rubber band rests on the hinge 

-Put the tower through the hinge

-Pull from the rope until the tower is in a vertical position

-Loosen the rubber band so that the weight of the tower and the mill will be carried by the rope. Hold the tower stright while doing this

-Lower the end of the tower in to the tank by giving out the rope gradually. Hold the tower stright

-Strap the tower to the beams

Lowering is done by undoing the steps taken in the raising of the windmill

Location of the part​s

All the parts are in or at the Big Catamaran. The rope behind the orange bag in the picture is suitable for the project.


Project start: 
June, 2016