Introduction: Solar Powered Rotating Strawberry Tower

About: I like to do electronics, metalworking, woodworking, fixing things and all sort of cool and stupid things :) I also have a YouTube channel: http://www.youtube.com/c/JTMakesIt

Here is a scenario:

- You live in an apartment and you have a small balcony, or you live in a house with no garden.

- You want to grow a lot of strawberries (or other veggies) on a very small place.

- You want a strawberry tower, but the sun will shine it only from one side and the rear half of the tower will grow badly.

- You are sad about that

In this Instructable you will find an answer to your problems :)

A solar rotating strawberry tower! Aka. Environmentally Friendly Vegan Kebab :)

It uses a small solar cell and a small DC motor to rotate the tower very slowly - 0.6 revolutions per minute to be precise. This way all the plants get equal amount of light.

In this Instructable I will explain step by step, on how I made this solar strawberry tower and I will provide you with all the necessary details for you to make your own.

But first watch the video of my build in the next step , so you will clearly see what is it all about. This is one of the best videos I made on my you tube channel. It has the highest production value so far and I am really proud of it :)

Step 1: Video of the Build Process

See the video to get a good idea of how everything is made.

I spent a lot of time editing this video and it came out quite professional. Tell me what you think!

Step 2: Materials and Tools

Here is the list of all the stuff used (affiliate links):

DC Motor: https://bit.ly/35CNPRQ

Axial Bearing 20mm * 40mm * 14mm: https://bit.ly/3iU0uYu

Solar panel:

Banggood: https://bit.ly/2TMeBok

Aliexpress: https://bit.ly/3JnIYXu

3D prints: https://www.thingiverse.com/thing:4890471

I made the tower from steel tube which I already had and I had to do some more modifications to it. The tube was originally made by a local guy who makes rain gutters for houses and he is very good with sheet metal.

I cut the holes with my cheap plasma cutter, but there are also some cheaper options.

If you don't have metalworking tools, you can make the tube from plastic PVC water pipe..

I made the holding bracket from steel and welded it with my welder. The bracket needs to be quite strong, because the tower full of dirt and water can easily weigh more than 50kg (100lbs). Mine is ridiculously strong, but I used what I had in hand. I encourage you to modify the design according to the stuff you have laying around.

I made the aluminium shaft with my lathe and a tower with a plasma cutter, but you can make this DIY project with much simpler tools (links to the tools I used are below -affiliate links)

Here are some tools from Banggood that I use all the time. Banggood has a great range of all sort s of tools which I like to use because they are good and cheap :) I also have a lot of reviews of these tools on my YouTube Channel

Banggood Plasma Cutter:

220V version: https://bit.ly/3gkveQR (also in EU stock, 1 week delivery!)

110V version: https://bit.ly/2RSCKsQ

Banggood Mig-250 Welder:

version 1: https://bit.ly/3weJwHW

version 2: https://bit.ly/3yg4ZSt ( 174$ with coupon BGMICZ32 - save 80$)

They also have an anniversary sale right now and you can grab some cheap tools here if you like to support me(these are affiliate links) so I don't go completely broke, writing all these Instructables and making Youtube videos :)

Coupon Deals With Great Discounts https://bit.ly/385mI3k

Best Deals https://bit.ly/3B7eBQd

Auto&Moto, Tools, Electronics Sale https://bit.ly/2WkmgeI


Step 3: The Tube

I cut some holes in the tube with my cheap plasma cutter. Originally the holes were too far apart.

You can also make the tube from PVC pipe used for waste water. It is easier to work with plastic, but the metal one is nicer in my opinion.

In the tube you also want to install water droppers or else the tube will be very hard to keep watered.

The dripper tube shall be placed in the middle of the tube. Ideally you would install a porous dripping hose, but I didn't have it at hand and I installed what I had laying around. On the side I places a garden hose connector so I can hook it up to a garden hose and let it drip for a while.


Another thing I forgot to do was to offset the holes so they are not directly above one another but offset by half, so the strawberries on the layer above don't directly hang on the ones below.


Then fill the tube with planting soil and pack it well with a stick. If you don't pack it well enough, the soil will eventually settle down by itself but it will drag the strawberries down into the holes by doing it.

Step 4: The Driving Mechanism

Here is how I envisioned the assembly of the driving mechanism.

It consists of the following parts:

DC motor, Bearing, Aluminium shaft and thee 3D printed parts.

Everything is mounted to the 60mm wide 5mm thick steel plate.

More on that in the following steps.

Step 5: 3D Prints

You want to print the 3D parts you can find here:

https://www.thingiverse.com/thing:4890471

The bottom bracket holds the axial bearing in place.
The top bracket screws on top of the bottom one and holds the geared DC motor.

The cover is a lid that protects everything from the weather.

Step 6: The Steel Frame

You need a sturdy frame to hold the tower. The tower can weigh more than 50kg, so the frame needs to be strong.

I welded it from a 5mm thick flat steel.

The bottom one is 60mm wide so the 3D printed cover fits over snugly. In that bracket you need to drill at least a 22mm hole so the shaft will go through.

Other dimensions are not critical and can be done according to your needs.

I am using a cheap Banggood MIG welder (linked in the third step) which works pretty well. If you want to know more about it, check out my youtube channel, I have a review video there.

Step 7: The Shaft

The shaft is a difficult thing to make since you need a lathe to make it as I did. See the video of the detailed process.

The body of the shaft is 20mm (which fits through the bearing) and it has a wider lip which seats on top of the bearing and holds the entire weight of the tower.

The shaft slides on the motor and has a screw which locks it onto the D-type shaft of the motor.

But in reality you can make it without the lathe.

You can take a 20mm aluminium rod (which fits through the bearing) and to make the lip, you can cut a thin slot around the shaft with a saw and install a locking seeger ring which will sit on the bearing and carry the whole weight. Then you make the rest with an angle grinder and drill.

Step 8: Wiring

Now assemble the bearing and 3D printed brackets together with four m3 screws.

Now it is time to wire the electrics.

In the video you will see that I used a LM7812 voltage regulator. That was because I was still waiting the 12V solar cell. At home I had 17V solar cell and I needed to reduce the voltage a bit.

But if you use the solar cell I recommended:

Banggood: https://bit.ly/35CNPRQ
Aliexpress: https://bit.ly/35CNPRQ

you don't need to use a voltage regulator. You can wire the solar cell directly to the motor.


I installed a pre-made female DC power connector which offers some environmental protection:

https://bit.ly/2Ulk2L6

These cables come in handy and make everything a bit more professional.

The solar cell plugs directly into this connector.


The motor draws only around 10mA when idling and up to 100mA at full load. So this solar cell is a perfect fit for this application. Not too big and not too small.

Step 9: The Cover

I sprayed the cover with silver paint, so the 3D print should be slightly more weather proof and UV light resistant.

Step 10: Solar Cell Holder

I mounted the solar cell on a simple bent piece of aluminium. In our town there are occasional strong winds and I couldn't just hang the cell on a hook as it would fly off.


See the video, you will see how I fixed it to the plate.

The bender I used to bend the plate was my first ever prize I got from Instructables when winning a metalworking contest with my first ever instructable :)

Step 11: Plant the Strawberries

Insert the strawberry plants in the holes and and some moss or some other fabric that will prevent the soil from falling out of the holes in the long run.

When you are finished, the tower will look a bit weird, but the strawberry leaves will eventually turn right side up and it will look much better :)

Step 12: Hang the Drive Unit on Something Tall

Attach the drive unit on something tall with some rope or something fancier like I did.

Then hang the tower on some chain and use a swiveling carabiner.

This carabiner makes it easier to attach and detach the tower from the motor and it serves an important function of protecting the motor by acting as a clutch.

If a tower gets jammed or it is spun with a great force in a wind or by someone, the carabiner will spin and protect the motors internal gears from breaking due to a big force pushing on them.

Step 13: Enjoy Your Creation!

That is it!

Watch the thing spin and wait for the strawberries to become red!

I hope you liked this Instructable!

Don't forget to watch the you tube video on the top of the Instructable, where you will see me going through everything described here in great detail.

I do a lot of Instructables and DIY themed YouTube videos.

If you want to stay in touch on what I am currently working on:

You can subscribe to my YouTube channel(click the bell icon to get notified, since I only post approximately once a month):

http://www.youtube.com/c/JTMakesIt

and follow me on Facebook and Instagram

https://www.facebook.com/JTMakesIt

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and or spoilers on what I am currently working on, behind the scenes and other extras!

And don't forget to follow me on Instructables and vote for this Instructable in the "Backyard" contest :)

Cheers!

JT

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