HowTo: WinDIY – Assembling the pitch actuator

One component that is supposed to make WinDIY more secure is the pitch actuator.

It allows the wing’s angle of attack to be changed via a push rod. In case of an emergency (e.g. if the speed is too high) the angle of attack can then be changed so that the wind can no longer transfer enough energy to the blades.

Especially in strong winds the speed can in this way be reduced effectively.

How to build the pitch actuator is described in the following article.

Safety instructions

I know the following hints are always a bit annoying and seem unnecessary. But unfortunately, many people who knew it "better" from carelessness lost their eyes, fingers or other things or hurt themselves. In comparison, a loss of data is almost not worth mentioning, but even these can be really annoying. Therefore, please take five minutes to read the safety instructions. Even the coolest project is worth no injury or other annoyance.

Affiliate links / advertising links

The links to online shops listed here are so-called affiliate links. If you click on such an affiliate link and shop via this link, receives a commission from the online shop or provider concerned. The price doesn't change for you. If you do your purchases via these links, you will support in being able to offer further useful projects in the future. 🙂


Helpful article:
For the assembly of the pitch actuator you only need patience and a few simple manual skills besides the parts and tools. You can find tips for the individual steps in the following articles:
Mechanics – Cutting internal threads

Required tools:

Hot glue gun
3D printer
Allen key
soldering iron

Required material:

In the following list you will find all parts you need to implement this article.

4xM3x50 countersunk screw
6xM3x25 countersunk screw
2xM3x16 countersunk screw
15xM3 nut
2xM3 grub screw
1x603ZZ ball bearings
1x606ZZ ball bearings
1xM6 nut
3xM3x40 cylinder head screw
1x3-6V gear motor
ca. 10cmShrink tubing
ca. 1mWires (different colors)
1xB103 B10K Ohm Potentiometer 10K 75mm SC6080GH

The required parts

On the picture you can see the needed parts.

You can find the plastic parts shown in the Nerdiy-GitHub. Here:

I printed the parts with the following settings.

  • Perimeter: 5
  • Infill: 30%

The screws should preferably be made of stainless steel so that they do not rust from moisture.

Preparation of individual parts

Before you can start assembling the whole pitch actuator unit, you should first prefabricate a few smaller components. For example the drive gear and its carrier.

The drive gear is supported on one side by a 603ZZ ball bearing. On the other side it is mounted on the motor axle of the drive motor.

First you need the parts shown in the picture.

Then insert the ball bearing into the corresponding recess on the face of the gear as shown.

Make sure that the gear wheel is as level as possible in the recess.

Seen from the side, the ball bearing should hardly stick out of the gear wheel.

To be able to fix the gear wheel on the motor axle later, you should now screw in the two grub screws as shown.

You may have to cut a thread in the holes first. How you can do this is described in the article HowTo: Mechanics – Cut internal threads.

Seen from above this should look like this.

Make sure that you screw in the screws as shown (not too far).

Now the gear carrier is prepared. For this you need the shown parts.

Insert the screw into the gear carrier as shown.

On the other side you can then screw on the nut.

Close-up of the screwed-on nut.

For a first test you can screw in the screw completely.

Different view.

Later you will have to loosen the screw again to insert the gear.

Assemble the prepared parts

Now you can start with the actual assembly.

For the final assembly you now need the previously prepared components and the remaining parts shown.

First you have to insert the M3 nuts into the base of the pitch actuator as shown.

Close view of the inserted M3 nut.

Further close view of the inserted M3 nut.

Further close view of the inserted M3 nut.

Next you have to insert the M3 screws into the gear carrier as shown.

Until they look out of the gear carrier on the opposite side.

You can then insert the gear carrier into the base of the pitch actuator as shown…

… and screw with the previously inserted M3 nuts.

Further view of the screw connections.

Ready screwed the whole thing should look like this.

Now you have to insert the previously prepared gear into the carrier.

To do this, you may have to unscrew the screw from the gear carrier again.

The gear wheel can now be inserted into the recess as shown.

Then you can screw the screw back into the gear carrier and thus also into the hole of the ball bearing in the gear.

For the bearing of the gear wheel on the other side you now need the shown parts.

First place the ball bearing in the recess in the base as shown.

The illustrated axle carrier can then be inserted through the ball bearing…

…into the gear wheel.

Another view of the inserted axle carrier.

You can then screw the inserted axle carrier to the gear wheel using the prepared M3 grub screws.

Additional view.

Installing the gear motor

In order to drive the gear wheel later, a motor is obviously necessary. You can see how it is installed in the following paragraph.

For this you first need the shown parts.

Now first insert the axis of the geared motor into the axis carrier.

The motor should then be plugged into the base as shown.

To keep it in place you can screw it into the base with the shown screws.

Insert the screws into the motor housing up to the stop.

The screws are screwed on the back with the inserted M3 nuts.

Now the whole thing should look like this.

To have an anchor point for the shaft to adjust the pitch angle, you now have to fix a M6 nut in the base.

For this you need the shown parts.

First insert three M3 nuts into the base as shown.

The M6 nut is then inserted as shown.

When fully inserted, it should look like this.

To prevent the M6 nut from falling out, you can secure it with the shown plate.

Screw the plate to the base.

View of the screwed plate.

Connecting the pitch actuator to the base plate

In order to mount the pitch actuator correctly, you have to mount it on a base plate. This is described in the following paragraph.

For this you need the shown parts.

Insert four M3 nuts into the base of the pitch actuator as shown.

Using four M3 screws you can now screw the base plate…

…to the base of the pitch actuator.

When screwed together, the whole thing should look like this.

View of the opposite side.

Attach cables and install sliding resistor

In this step, the cables are attached to the motor and the sliding resistor – via which the pitch position can later be read in – is glued in.

In this picture the supply lines of the gear motor are already soldered on.

I strongly recommend securing the connector contacts with some hot glue after soldering.

Not just so that the contacts are electrically isolated. But also to protect the fragile contact lugs from mechanical stress caused by bending.

Now it is time to wire the slide resistor.

As you can see, this one is already wired.

For this you need three cables and three pieces of shrink tubing approx. Two cm long.

On the side shown, the contact of the wiper is connected to a line.

On the other side, the two contacts of the resistor are each connected to a line.

Close-up view of the connected resistance contacts.

Close-up view of the connected wiper contact.

Another view.

Now you can attach an adapter to the grinder.

Simply put it on the metal surface of the grinder.

Close-up view of the adapter attached to the metal surface of the grinder.

After the sliding resistor has been wired, you can glue it into the holder provided with a drop of hot glue.

The lines should run out of the bracket as shown.

The construction of the pitch actuator is now complete.

Another view.

Another view.

Have fun with the project

I hope everything worked as described. If not or you have any other questions or suggestions, please let me know in the comments. Also, ideas for new projects are always welcome. 🙂

P.S. Many of these projects - especially the hardware projects - cost a lot of time and money. Of course I do this because I enjoy it, but if you appreciate it that I share these information with you, I would be happy about a small donation to the coffee box. 🙂

Buy Me a Coffee at   

Leave a Reply

Your email address will not be published. Required fields are marked *