A self-watering planter is cool and if it rotates automatically it's amazing. All sides of the plant get even exposure to light and ideal for delicate cutting or seedling. Today I will share the recipe of my rotating planter I designed using Tinkercad a web-based easy to use free 3D designing tool. The planter is self-watering. So, you can plan an outside trip for two or three weeks keeping it unattended. Rotating mechanism is enabled by a 9g micro servo and an AA cell.
Step 1: Assembly & Operation
This video shows how to assemble all the 3D printed parts and how it operates. After printing all the parts you will be able to assemble all the parts following the video. It is very simple to follow. No hard step!
Step 2: Bill of Materials
1. Generic 3D Printer: I use Anet A8, a low price excellent quality 3D printer. I am using this printer for about 1 year and I am very much satisfied with the performance of the printer. You can buy Anet A8 from Gearbest for $140. The printer is available in Kit form and buying this you can get the pleasure of building a 3D printer yourself.
2. Micro Servo (9g) (Gearbest.com): You will be required to make some modification on the servo. You have to remove the controller circuit of the servo because we will use this as a DC geared motor and power it up using a single AA cell. You also need to convert the servo as continuous rotation servo. To do that you may follow the nice instructable CONVERTING MICRO-SERVOS FOR CONTINUOUS ROTATION.
3. AA Cell: You can buy this from any glossary or electronic shop.
4. Battery holder spring contact (digikey)
5. Bearing ball: I collected some balls from a ball necklace.
6. Woolen thread
7. A soldering Station: You can buy this adjustable temperature soldering station from Gearbest.com for $42 at 36% discount. It has rapid heating and rewarming capacity and especially suitable for lead-free soldering and soldering. It has a 3 digit seven segment display and can heat up 450 degree Celcius.
Step 4: 3D Designing
All the necessary parts for the planter was designed in Tinkercad. Tinkercad is a web-based 3D design platform and very easy to use. You just need to register to use it. You can also use your Gmail credentials to log in. The Tinkercad link is here: Tinkercad: https://www.tinkercad.com/things/rotating-planter. You can also find the details of my design from Thingiverse and MyMiniFactory. All the STL files are also attached in the next step.
My Thingiverse: https://www.thingiverse.com/thing:2958841
Step 5: 3D Printing
I printed all the files using my Anet A8 3D printer. Anet A8 is an excellent 3D printer at a very low price. You can buy the printer for only $140 from Gearbest.com. I am using this printer for more than 1 year and I got it very convenient. Print quality is also satisfactory.
All the files can be print without any support. 20% infill may be adequate and I printed all with PLA. If you print all in first printing mode it may require approximately 12 hours. All the necessary files are attached below. You may download and print directly.
Step 6: Modifying the Servo
A standard servo can rotate only 180-degree clockwise and anti-clockwise. Besides a special PWM signal is required to control a servo motor. At least 3.5 Volts is required to power up a servo motor. To overcome all those constraints and rotate it continuously with a single AA cell we need to modify the servo.
First, modify the micro servo for continuous rotation. You may follow this nice instructable Converting-Micro-Servos-for-Continuous-Rotation for successfully preparing the servo for continuous rotation. As we like to run the servo motor as simple geared dc motor we need to remove the control circuit inside the servo and directly connect the positive and negative lead of the motor to the output wires. So, now the motor has only two wires instead of three wires and ready to drive it from a single AA battery as a geared dc motor.
Step 7: Assembling (Part 1)
The bottom base will also work as a battery holder. Solder two 20cm long wires to the spring contact and plain contact and place the spring contact and a plain contact in the two terminal of the hole for the battery and bring out the output wires through the hole of the base. Place the servo motor to the upper base with two screws and connect the gear horn with the servo. Solder the output to the wires of the motor with an on/off switch. Connect the top base with the bottom base. Place some balls in the circular ball holder and then place the reservoir with the main gear on the upper base.
Step 8: Assembling (Part 2)
The speed of the planter is reduced by gear. The gear ratio is a very critical parameter and it has huge significance in terms of drivability as well as fuel economy. Gear ratios will determine if the engine will run at high RPM (which may deliver more torque, consume more fuel) or low RPM (which means the torque is less but fuel consumption is also less) for a given wheel speed. Overly high RPM can cause engine noise as well as loss of Fuel Efficiency, whereas overly low RPM can cause engine lugging and loss of engine power. The gear ratios need to be very carefully designed considering the vehicle weight, engine torque and power curves, intended drivability and performance parameters and of course intended fuel economy.
This part is very simple. Bring out some woolen thread to the holes of the inner planter from inside to outside. These threads will draw water from the reservoir when required. Then place your favorite plant in the planter with some soil.
Your planter is now ready. Place the main planter pot in the reservoir, turn on the switch and enjoy.