WIND MASTER MECCANO MODEL
constructed and written by Neil Pluck
photos by Steven Reid

It all started at the New Zealand 2001 Meccano convention at Wellington. Brian Hickson talked about a challenge for someone to build a wind-powered land vehicle as a Meccano model for the Hawera 2003 convention.

The basic rules for the wind-powered vehicle are:-

1 - The vehicle shall be a wind-powered land vehicle.
2 - The tractive effort is to be applied through either wheels or tracks or a combination of both.
3 - The model must be capable of controlled changes of direction regardless of wind direction.
4 - The model when placed on a reasonable level playing field or car park in a 10 to 15 kph plus wind will demonstrate that it is able to move and change direction.
5 - The model must be made from Meccano with the exceptions of rubber bands, protective devices and springs.

I thought about it and decided to have a go at making a wind-powered vehicle according to these specifications, as it would be a great challenge. I knew little about wind power. After much research about wind power, I first had to decide what sort of blade arrangement to use. I made two prototypes, a vertical cylindrical vane and a horizontal two-blade type. The cylindrical type did not seem to start in light wind very well as the wind would have an effect on both sides and it did not turn.

The two-blade type moved easier, therefore I equipped the wind machine with three blades, which was even better. However Meccano being Meccano it was harder to mount three blades as most Meccano round parts are divided into four. I tried a six hole Bush Wheel to hold the blades onto the shaft but it was not strong enough to support three blades. I went to four blades, which was better still.

Variable Pitch Propeller Hub with spring and 31/2“ Gear removed:
Originally the model had fixed blades but with wind gusts it would go up to very high speeds, causing it to throw apart. I needed adjustable blades to control wind gusts so in the end it was overcome by making a variable pitch blade. The blades are pivoted on Axles located in the Hub Disc with a Pawl mounted on each Axle. When the wind pushes against the curved blades the Axle would rotate moving the Pawl towards the spring loaded 31/2“ Gear moving the Gear away from the Hub and the blades would flatten out to stop wind surges. The blade spring tension and travel is adjustable. This was made with a lot of trial and error. However when I was satisfied with the veritable blade mechanism I moved onto a tower of some sort that had to fit into the car to transport it without having to take too much apart to enable it to go to the Hawera 2003 convention.

Limited Slip Differential:
I started with a tower using 241/2“ Angle Girders and a wide base to make it stable. As it was not having suspension I decided to make it with three wheels so it

would sit flat on the ground no matter how rough the ground was. That idea was soon changed when a sudden wind gust tipped my wind machine over with the blades in full flight, Meccano flying everywhere. I ended up with some bent Meccano. This helped me decide that the conventional four wheels with one in each corner would be better. A normal differential would not be any good on uneven ground as one of the driving wheels may leave the ground and it would stop driving so I used a limited slip differential designed by Graeme O’Neill from the Christchurch Meccano club a few years ago. This design allows the vehicle to still drive forward if one of the wheels loses traction. Dual wheels were added at the rear for extra traction on uneven surface. All the time the vehicle is getting heavier.

Counter Rotating Flywheel and Adjustable Free Running Bearings.
The wind machine was starting to take shape and was getting ready for another test run. On this test run I found that as the blades rotated it caused a gyroscopic

affect and had tendency to walk the top around the centre locating rod and turn the blades away from the wind. Therefore the top was removed and rebuilt, this time it was built with a counter-rotating flywheel to rotate in the opposite direction so as to counteract the rotational forces of the blades. When the counter-rotating flywheel was fitted it stopped the top from moving around, and made the drive smoother in operation. Also the propeller and flywheel shafts were mounted with low friction bearings, which made the blades easier to rotate in lighter winds. Getting the blades balanced was very hard, you had to balance each blade individually and then make the hub balance. Adding extra parts, Washers or Nuts and Bolts did this.

Mock Up of Turntable Drive.
The drive from the propeller shaft was driven down to the Roller Bearing off centre so it was not driving through the centre shaft, which was only locating the two

halves. If there were any movement sideways it would not load the drive shaft. The drive went through two 1” Gears back to the centre shaft with a Socket Coupling and two 1” Sprocket Wheels. I had to use them to get clearance between the two Hub Discs with the 1/2“ Pulleys running between them.

Governor and Gearbox.
I could have used Pinions and Gear Wheels but it would have caused a gear reduction to the drive that went down to the governor-controlled gearbox. The

three-speed gearbox and governor would not get up enough speed to operate. The drive then went down to the base and across to the differential and down to the rear wheels via the chain drives. At different points along the driveline I could change gears to alter gear ratios if needed. Without the gearbox it moved very slowly as it had to be geared down to get its weight moving.

Gear Drive from Differential to Steering.
As the machine had to show that it could function in all wind directions I fitted automatic steering so it would do a figure 8 pattern. The drive for the steering was

taken from the differential drive and driven to the front and across to the centre to rotate, a 6” Circular Plate that was connected to the steering; as the plate rotated it moved the steering back and forth to make it travel in a figure 8. In a light wind it took about 45 minutes to travel that distance. The front wheels were mounted on ball bearing races for extra strength and ease of turning because the load is spread over a bigger area.

Overview Looking Down on the Rotating Top.
Specifications:

The Final Road Test.
The tower was not high enough for a built-up area as the blades were susceptible to wind turbulence but it was all right in an open area. Its performance would be affected with the extra weight if the tower were taller. It was a really great experience building a model powered by something other than battery or electricity. It is unfortunate that as I could not make it to the Hawera 2003 convention. I have dismantled the machine, but even more unfortunate is that I have found out since that the competition has been carried over for another two years to the Auckland 2005 convention.

Back to Home

Back to Magazine