I've probably already mentioned at one point or another that it was important to me to be able to control WinDIY safely and also limit its speed in an emergency.
To do this, I developed a mechanism that makes it possible to adjust the angle of attack of the wings. This allows the blades to be adjusted to the current wind and rotation speed. They can also be turned out of the wind in strong winds.
This allows you to control the speed and load of WinDIY.
I have written down some additional information about this here: https://hackaday.io/project/172328-windiy-hawt-wind-turbine/log/179105-windiys-hub-oh-my-god-mechanics
In the following article you will find instructions for replicating the mechanics for adjusting the wing angle of attack.
Safety instructions
I know the following notes are always kind of annoying and seem unnecessary. Unfortunately, many people who knew "better" have lost eyes, fingers or other things due to carelessness or injured themselves. Data loss is almost negligible in comparison, but even these can be really annoying. Therefore, please take five minutes to read the safety instructions. Because even the coolest project is not worth injury or other trouble.
https://www.nerdiy.de/sicherheitshinweise/
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The links to online shops listed here are so-called affiliate links. If you click on such an affiliate link and make a purchase via this link, Nerdiy.de will receive a commission from the relevant online shop or provider. The price does not change for you. If you make your purchases via these links, you support Nerdiy.de in being able to offer other useful projects in the future. 🙂
Requirements
Required tool:
Hot glue gun |
3D Printer |
Allen wrench |
Tongs |
Open-end wrench |
Cordless drill |
3mm drill bit |
Tweezers |
Required material:
In the following list you will find all the parts you need to implement this article.
3x | pitchArm |
3x | pitchLever |
3x | pitchArmNutSecuring |
1x | hubBase |
1x | pitchLeverDisk |
1x | hubCover |
1x | hubBearingCap |
9x | 603ZZ ball bearings |
8x | 606ZZ ball bearings |
5x | M6 self-locking nut |
6x | M6 mother |
3x | M3x20 cylinder head screw |
3x | M3 self-locking nut |
15x | M3 nut |
3x | M3x30 countersunk screw |
3x | M3x16 countersunk head screw |
6x | M3x40 countersunk screw |
3x | Prepared wing slot |
1x | M6 threaded rod 60cm long |
Collect required parts
Before you can start building the hub and its mechanics, you must of course first have all the necessary parts together. You can find a complete list of the materials and tools required above in the materials and tools list
You can find the required STL files for printing here: https://github.com/Nerdiyde/WinDIY/tree/master/hub
I printed the parts with the following settings.
- Perimeter: 5
- Infill: 50%
The screws should preferably be made of stainless steel so that they do not rust due to moisture.
Mount the hub base on the axle
First, the hub base must be connected to the axle. This actually makes further assembly a little more complicated. Unfortunately, this has to happen right at the beginning, as the screw holes used during assembly are difficult to access later.

To do this you will first need the parts shown.
The axle, the hub base, 3x M3 nuts and 3x M3x50 countersunk screws.

Je nach Druckqualität Eures Druckers kann es sein, dass Ihr die Mutter etwas in die richtige Position „zwingen“ müsst.

You can then insert the remaining screws into the hub base and screw them into the axle with the nuts.
The axle should now be screwed to the hub base using three M3x50 countersunk screws.
Install the first wing slot
The wings are not directly connected to the hub. Initially only the slots are connected to the hub. The wings can then be inserted onto it later.

To do this, place the first 606ZZ ball bearing from the outside into the recess in the hub base as shown.

Now you can insert the first wing slot.
You should have already prepared this wing slot while assembling the wing.

The first securing of the sash consists of a self-locking M6 nut, which is screwed onto the M6x100 screw of the sash slot.

Once screwed on, it should look like this.
The nut should be so tight that the wing slot can no longer be moved in the direction of the screw. At the same time, of course, it should still be rotatable.

To do this, push the 606ZZ ball bearing over the M6x100 screw into the recess on the inside of the hub base...
Attach lever and adjust correctly
Now comes a somewhat critical step in which you should work as precisely as possible. To be honest, I'm not yet completely satisfied with the mounting of the lever on the M6x100 screw of the wing slot. This is secured by clamping between two nuts on the screw. In theory that should hold. In practice it does that too. However, it would be safer to put a split pin through the M6x100 screw, for example. There is certainly room for future improvements here. 🙂

To adjust the lever correctly, you should now position the hub base a little higher. For example, I put them on two boxes.

The goal is for the back edge of the wing slot to be exactly the same height as the back of the hub base.

Once you have set the wing slot correctly, you can now attach the lever to the axle and to the previously screwed-on M6 nut. The nut should fit as tightly as possible to the ball bearing, but the entire wing slot should still be able to rotate freely.
As soon as the lever is inserted correctly...

...you can temporarily secure its alignment in the hub base with an M3 screw (the screw will be removed again later). (see image)
Install guide ball bearings
In this step, the ball bearing is installed that allows the push rod to adjust the wing angle of attack. Actually, this step could have been carried out before installing the wing lever.
Mount the remaining two wings on the hub
After the ball bearing for guiding the push rod is installed in the hub base, you can proceed with installing the remaining two wing slots. These are installed using exactly the same procedure as the first wing slot.
Attach the nut lock
As already mentioned above, the levers for adjusting the wing angle of attack are clamped on the M6x100 screw of the respective wing slot. So that the inner nut can no longer loosen (and the lever would no longer have any effect on the rotation of the sash), you should now urgently secure this nut against twisting.

Before you secure the nut, you should make sure that the internal nut is tightened as tightly as possible.
Of course, the setting of the lever should not be changed.
So first check that the angle of the lever to the sash slot is correct and then tighten the nut as tight as possible.
„Fest wie möglich“ heißt hier so fest, dass Ihr es „per Hand“ unter Einsatz eines Schraubenschlüssels nicht mehr fester bekommt.

Now you need an M3x20 cylinder head screw, an M3 nut and the 3D printed plastic part to secure the lever.

Now you can also check that the levers are at the correct angle to the wing slots.
If the wing slots are straight (as shown in the picture)…

—the levers should touch the stops on the hub base. The angle of rotation of the wing slots is therefore limited in one direction.
„Hebelstrecker“ anbringen
(Btw: Sometimes it's not easy to find suitable names for the individual parts. 🙂 )
In diesem Abschnitt geht es darum an den zuvor montierten Hebeln den „Hebelstrecker“ anzubringen. Dieser Ist Teil der Mechanik, welche aus den vor- und zurück-Bewegungen der Schubstange später eine Drehbewegung für den Flügel macht.

To do this, you first need a 3D printed lever extender, an M3x20 cylinder head screw and a self-locking M3 nut.
Attach lever plate
Hier kommt das nächste wichtige Teil für die Mechanik zur Einstellung des Anstellwinkels: Die „Hebelplatte“.

So that you can now fix the screw, you now have to insert an M3 nut into the recess on the top of the lever plate.

If you now move the lever plate back and forth, you should notice that the wings can be adjusted according to the distance between the lever plate.
Insert ball bearing at anchor point
So far we have used a ball bearing that is intended to guide the push rod.
Now the ball bearing is mounted, via which the thrust movement of the push rod is transmitted to the lever plate.

To do this you need the ball bearing locking plate, a 606ZZ ball bearing, three M3x16 cylinder screws and three M3 nuts.

Now secure the ball bearing in its position by mounting the ball bearing locking plate including the three M3x16 cylinder head screws on the lever plate.
Attach stabilizing ring
In order to give the hub base a little more stability, a stabilization ring is now mounted on the hub base.

To do this you need the 3D printed stabilization ring, six M3 nuts and six M3x40 countersunk screws.

To do this, screw the M3x40 screws into the nuts, which are inserted into the recesses on the underside of the hub base.
Attach push rod
The push rod consists of an M6 threaded rod. It will later transfer the thrust movement generated by the pitch actuator to the mechanics in the hub.

At this point you need the previously prepared hub base including attachments as well as two self-locking M6 nuts and an M6 threaded rod.

Then pull the push rod back a little and screw the first self-locking nut onto the push rod as shown.
Unfortunately, the nut cannot be seen but is located in the socket wrench, which makes assembly much easier.

It is also helpful if you clamp the threaded rod in a cordless screwdriver as shown. This way you can easily turn the threaded rod into the M6 nut.

So that the push rod remains in the upper ball bearing, you now have to screw the other M6 nut onto the push rod as shown.
The push rod should now sit firmly in the ball bearing without much play.
Now it's time for a first test.
Attach cover
Last but not least, the hub now has a cover. On the one hand, this covers the mechanics and should protect them from moisture and rain. On the other hand, it makes the hub a little more aerodynamic.
Have fun with the project
I hope everything worked as described for you. If not or you have questions or suggestions please let me know in the comments. I will then add this to the article if necessary.
Ideas for new projects are always welcome. 🙂
PS 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 think it's cool that I share the information with you, I would be happy about a small donation to the coffee fund. 🙂
A total of 6 pieces of the 606ZZ ball bearings are required. Only 2 pieces are mentioned in the material list.
Thanks for the hint. Corrected the relevant passage.
Best regards
Fabian
Small correction. 😀 A total of 8 type 606ZZ ball bearings are required. Two extra for the threaded rod that goes through the axle.
Thanks for the hint! Updated the materials list. 🙂
Best regards
Fabian