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The first windmill model I built was just like the one that belonged in our family two hundred years ago. It was a "post mill" used to grind wheat into flour. Now I would like to make another windmill and show you how I do it as we go along. This will be a "top-wheeler"; so named because only the round top can be rotated in a horizontal plane. This movement is necessary to make sure the blades are positioned correctly to account for changes in wind direction.
But wait, before we build a model, let me explain a few things about windmills that are important in understanding the details of our model.

One use for windmills was to pump water out of the lowlands. To lift water from the meadows to sea-level required three or four stages. Hence, more than one windmill would act in unison as shown above. Note the small ditch to the right and one much higher to the far left. The latter would drain into the river. These top-wheelers had the blades almost touching the ground. They were built in open fields or on dikes where they could catch the wind without interference from surrounding trees or buildings.

If the mill was located near a village with surrounding houses and trees, it was necessary to elevate the blades. Thus, we have the "tower mill". These were mostly grain mills with heavy stone grinding wheels that required more power to do the work. Some top wheelers had a mechanism inside the building to rotate the top into the wind. However, most were adjusted outside using a capstan wheel and big beams going up to the top. These beams provide the leverage needed to rotate the heavy structure. Two good examples of this are the windmills in Varik and Zuilichem where our ancestors lived.

If the mill was located near a village with surrounding houses and trees, it was necessary to elevate the blades. Thus, we have the "tower mill". These were mostly grain mills with heavy stone grinding wheels that required more power to do the work.

Some top wheelers had a mechanism inside the building to rotate the top into the wind. However, most were adjusted outside using a capstan wheel and big beams going up to the top. These beams provide the leverage needed to rotate the heavy structure.

Two good examples of this are the windmills in Varik and Zuilichem where our ancestors lived.

So, let’s start with our model. First we need some drawings. The plans I used came from Amsterdam and consisted of two drawings and some printed text that was of little use (a bad and confusing translation). I converted most of the drawing dimensions so they would be similar to my earlier scale model, 1:76. Just for reference, that equates to a six foot person being almost one inch tall.
The main tower is 65 feet high. With the blades in top position, the overall height will be 116 feet. That is 18 inches for our model; good enough for a high shelf.

		Now we need some materials. I use pine for most of the beams and slats. For the siding I use 1/16 inch thick Baltic birch plywood (3 ply). There is also some 1/8 inch thick plywood for the base and top of the main structure. Here you see the basic frame work. I cut my own wood to size. Then use a small bandsaw and hand tools including a Exacto razor saw for the small pieces. Carpenters wood glue holds it all together.

One of the double doors is open and the windows have a translucent piece of plastic. So we need a light inside. I had a small socket and bulb and placed this on the second floor as shown. To change the bulb I should be able to reach down from the top (may be). The spokes support the platform.

After cutting and laying 96 planks, it is time to make the railing. For this I made a fixture to glue the slanted posts and braces. The jig is also handy to file the top of the posts smooth and level so the railing can be added with a dab of glue.

Touch up the stained slats and pieces and add some trim along the vertical corner joints. This hides the gaps and provides some contrast. Now we are finished with the main tower.

Now comes the tricky part: making the top with the main shaft. Instead of using lots of individual pieces, I decided to use a solid block of wood made up of five sections of poplar. This is a relatively soft "hardwood"; easier to shape than oak, but better than pine as a pillow block for the main shaft. The drawing shows the shape of the top as a cross section, but the actual contours are all over the map. We make some paper templates for the five pieces and cut them to size. Once joined, they will require lots of carving and sanding.

As long as we want lights, we also want to have the blades turn. In my scrap bin I found a small electric motor that came from a microwave oven turn-table. Also there were two small gears that matched and a 3/16 inch piece of steel rod. So let’s see what that does for us. The motor output is 3 rpm. I like to see it go a bit faster for the windmill shaft. So what if we put the larger gear on the motor and the small one on the main shaft? Sorry, a bit of math is in order.

The large gear and the small gear have “root-diameters” of about 1.34 and 0.75 inches respectively. The ratio is the increase in rpm, or 1.79 x 3 = 5.4 rpm. The blades are about 90 feet in diameter. At 5.4 rpm the tip of the blade will move at 25 feet per second. That equates to 17 miles per hour. That seems OK, right? We don’t want this thing to move like hummingbird wings.

		Before we glue up the five pieces I drill the holes for the shaft at a ten degree angle. The brass gear will be installed later again and held in place with a couple dabs of epoxy. Here is the block of wood after some elbow grease.

Before we glue up the five pieces I drill the holes for the shaft at a ten degree angle. The brass gear will be installed later again and held in place with a couple dabs of epoxy.

Here is the block of wood after some elbow grease.

	With some stain, trim, three windows in the rear, and the two horizontal turning beams in place we have the following top. The next step is to construct the capstan and vertical beams that connect to the top at a compound angle. At this point I am afraid that the drawings I have do not allow enough clearance to the front horizontal beam. The beam may be too short, but we will find out when we make the rest.

Before we go further with the top and it becomes too delicate to handle, we want to mount the motor and plastic gear. I made a yoke out of a piece of mahagony, lined everything up and used screws to hold the motor on the yoke and the yoke to the bottom of the cap. All had to fit through the hole in the top of the building. I did have to use some shims to release the pressure between the two gears and then it was a trial run. I connected some aligator clips and plugged the cord into a 110 outlet. All worked fine and the shaft is ready to be cut to length and the brass gear glued to it. The end of the shaft was threaded (10 - 32) for a washer and nut to hold the "wieken" in place.

The turning beams and capstan were next. Indeed the forward horizontal beam was too short and I had to replace it with one that was about 1.5 inches longer. Otherwise the long slanted tie beam would not clear the sides of the building. I made the capstan ring from a piece of copper wire. However, I am not happy with the scale and may do this thing over again. The spokes and ring are too coarse. Here are also a couple of pictures showing the lights inside the mill.

The turning beams and capstan were next. Indeed the forward horizontal beam was too short and I had to replace it with one that was about 1.5 inches longer. Otherwise the long slanted tie beam would not clear the sides of the building.

I made the capstan ring from a piece of copper wire. However, I am not happy with the scale and may do this thing over again. The spokes and ring are too coarse.

Here are also a couple of pictures showing the lights inside the mill.

We are not yet done, of course. The most important parts are the blades or "wieken". However, I need a break; it is summer and hot in my shop. I will continue this page at a later date. Meanwhile here is an old Dutch riddle:

Vier ouden wijven Konden elkaar niet krijgen. Ze liepen even hard, Raai-raai wat is dat.	Four old women Couldn't catch each other. They walked at the same pace, Guess-Guess what is that.

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