## Introduction: Simple Gear Mechanism (Move Things)

Since childhood, I have been fascinated with gear and how it works. I was majoring in Economic and later get married. Since then, I did not have time to pursue my interest due to taking care of my family. Now, my sons have already grew up and they are very interested in engineering, so I can continue to learn my old interest.

This time I would like to share how gear mechanism works and how to apply those in our life.

Here is the assignment. My sons will create a gear mechanism. They should make a creation with those gears as the base to move things in 3D Models. For this time we do distance learning, they should use Tinkercad to create 3D Models and manage how to put and arrange the gears with the position that enables them to move things. This assignment does not limit what objects they will create. I just want them to focus on engineering about how the gear mechanism works, so they can make similar with my tutorial or different objects.

The objectives of this assignment are that they will able to understand:

1. What gear is

2. How gear works

3. How to calculate gear rotation

4. How to create gear, especially in a 3D environment

5. How to create everyday objects using gear in 3D model with Tinkercad

6. How to boost and promote creativity

## Supplies

3D Dremel Printer

3D Dremel Digilab Slicer

PLA Filament (Gold, Black, Green, See-through-blue, blue and red)

## Step 1: What Is Gear

Gear is part of machine that has function to rotate and has teeth around it. Gear is used in many aspects of everyday objects around us. The functions of gear are to increasing or decreasing the rotation's speed, reversing the speed's direction, and keep on rotating two axes together.

We can see that gear contributes in making things move. There are many objects using gear for their moving, such as bicycle, motorcycle, automobile, drill, non-digital clock, mechanical toy, etc.

## Step 2: How Gear Works

One gear can rotate the other gear if they are placed side by side. They come with many difference sizes. The smaller gear will have more speed, but less force. On the other hand, the larger gear will have more force, but less speed. When they connect together, they will rotate with opposite direction to each other. Gear can be connected with direct to each other and by chain as well, like in bicycle. The direction of driver gear rotation is always opposite of the driven gear.

## Step 3: How to Calculate Gear Rotation

To calculate gear rotation, we need to know about the gear ratio. We can use formula like this.

Gear Ratio = #teeth of output (driven) gear/ #teeth of input (driver) gear

For example, if the output gear has 20 teeth and input gear has 10 teeth, so the gear ratio is 20/10=2:1.

That means every time driven gear rotates 1X, the driver gear rotates 2X.

By calculating gear ratio, we can identify the Ideal Mechanic Advantage (IMA). If IMA is less than 1, it is called speed multiplier and If IMA is greater than 1, it is called torque multiplier. In the example above, we can say that it is torque multiplier. Some examples of torque multiplier are motorcycles and cars. Example of speed multiplier is bicycle. For more information, click here.

To make good efficiency, it depends on how we emphasize our application.

## Step 4: Creating Gear in a 3D Environment

To create gear in Tinkercad, we can make it in two ways. First, make manually using basic shape of cylinders. Second, Tinkercad also provides gear in the shape generator.

For beginner and first time learner, open here to access Tinkercad. Just create the account for first time user or sign in if you have an account in Tinkercad. Click create new design and rename it.

## Step 5: Making Gear Manually by Using Basic Shape

First, make the base by dragging cylinder to the workplane. Scale it as you desire. You can do the scales like mine.

Here is my scale:

Length: 10 mm

Width: 10 mm

Height: 5 mm

For best result, change the side. See the picture.

## Step 6:

Second, make the teeth by dragging another cylinder to the workplane, but this time make the cylinder rather ellipse. For scaling, it is up to you. You can do the scales like mine.

Here is my scale:

Length: 1 mm

Width: 3 mm

Height: 5 mm

## Step 7:

Drag the teeth to the base. Duplicate and place it on the other side of the base, but make sure it is in one straight line.

## Step 8:

Group both of the teeth together. Rotate them. Before you are doing the rotating, make sure how many teeth do you want for your gear. Just do the math calculation using this formula: #teeth= 360 degrees/ rotation degree. For example, if you want to make gear with 20 teeth, so you need 18 degrees for the rotation.(360 degrees/20 teeth) Make smart copy. It means Tinkercad will remember the previous pasting. Group them together. You are finished making one gear. Make as many gears as you desire for your design.

## Step 9: Making Gear by Using Shape Generator

Tinkercad also provides gears in the shape generator. Simply choose the type of gear that you want to use. There are gear, progear, metric gear, useful gear, cone metric gear, and custom gear. I chose the metric gear for my instruction of this assignment.

## Step 10:

Drag and drop metric gear from shape generator.

Make the same measurement as gear that I mention previously. Here is the scale:

Length: 13 mm

Width: 13 mm

Height: 5 mm

The length and width here is 13 mm because it is sum up with the length of the teeth.

Change the number of teeth to 18.

I am doing the same exact measurement as before to make a comparison between those gears.

## Step 11: Create Everyday Objects Using Gear in 3D Model With Tinkercad

With this assignment, I will teach my sons how to make a simple pencil organizer which is moved by turning gear.

Pencil Gear Organizer

Here is the result of pencil gear organizer.

## Step 12: Gears- Pt. 1

You will need 6 gears for pencil gear organizer. To have the correct gear, you should make all gears have the same size of their teeth. First, we need to make 4 gears that have the same sizes and teeth. Select the metric gear from shape generator. Drag it into the workplane. Change the color as you like (I use gold for the color). Change the number of teeth to 10 and change the scale (width and length: 18 mm and height: 14.84 m). At the center of the gear, you need to make a hole for attaching gear with base.

Drag cylinder to the workplane and scale it. Make sure align it. Select both and group them together.

Duplicate this gear, so you have 4 gears in total. Lastly, to make prettier, I reduce the height of one gear (it should be in the middle of other gears), so the height should be 12 mm.

## Step 13: Gears- Pt. 2

Second type of the gear will be connected to the base and become the center of 4 gears that you made previously.

Drag and drop metric gear to the workplane and set the number of teeth to 40. Change the measurement (length: 62.90 mm, width: 65.36 mm and height: 12 mm)

Because you will need the ground base for this gear, I make hole on the bottom of the gear by using cylinder. Align (to make the hole in the center of the gear) and group them together.

## Step 14: Gears- Pt. 3

Add one cylinder and place on top of the biggest gear. Scale and align it. Make some centers for the gear, so the gears can be attached easily by dragging a cylinder to the workplane. Place it on the top of the previous cylinder. Duplicate it, so you have 4 cylinders in total. For placement, just place all the 4 gears in previous step and arrange them nicely. Make sure the cylinder in the center of each gear. For scaling, it is up to you, just measure that the diameter should less than the gear's hole. Just remember, you have 1 gear that shorter than others. So, the center is also shorter than others, too. I took some screenshots for the measurement.

## Step 15: Gears- Pt. 4

Last gear is making 1 driver/input gear. The step is the same as previous step, only the measurement is different. Change the teeth to 15. The width is 25.44 mm, the length is 26.29 mm and the height is 12 mm.

Also make hole in the center of the gear by using cylinder. Align and group them together. For exact measurement, please see the pictures.

## Step 16: Ground Base

For making ground base, drag a box to the workplane. Scale it.

Width: 67.20 mm

Length: 92.40 mm

Height: 6 mm

Drag cylinder to the workplane for making center of gear. Make diameter of cylinder 12 mm and height of 21.60. Duplicate it. The diameter of second center is the same (12 mm), only the height is shorter (19.20 mm). Place the center nicely as shown in the picture, so it will fit with the gears.

## Step 17: Pencil Holder- Pt. 1

For making the pencil holder, drag cylinder to workplane. Scale it. Make sure the diameter is 10.80 mm and the height is 60 mm or more, not too short. Duplicate the cylinder and make hole. For the hole, make diameter of 9.60 mm and the height of 59mm. Raise the cylinder hole for 5 mm. Align and group them together. Duplicate it until you have 3 long cylinders.

## Step 18: Pencil Holder- Pt. 2

Make another cylinder with the same step as previous. The only difference is the height. The height of the cylinder is 10 mm and the height of the cylinder hole is 21 mm. Raise the cylinder hole for 5 mm. Align and group them together. Duplicate it until you have 3 short cylinders.

## Step 19: Print

To demonstrate how the gears move things, I print my design above.

Save and export file part by part to .stl file. Open 3D Slicer (I use Dremel Digilab 3D Slicer) and print it.

Just make sure to print all gears without support, medium quality at least and infill 20%.

Here are the results of my printing.

## Step 20: Assemble

Assemble all parts one by one. First, glue the pencil holder by using hot glue. Arrange all the gears as shown in the picture. Last, attach the pencil holder to the gear.

## Step 21: Final Result

Here is my final result of pencil organizer. I also print one of my son's creations of Boat Carousel. Special thanks to CREATIVETOOLS for providing my son in making boat carousel.

## Step 22: Examples of Work

Here are my sons' work examples of this assignment. All are making various carousels with different styles and gear mechanism. Moreover, all shows good understanding about how gear mechanism should work and move things.

## Step 23: Conclusion

I know this project is still far from perfect. It is only the beginning of making incredible and beautiful things in the future. Perhaps, the next step is that connected the gear with some motors. Thank you for reading my instructable. I really appreciate it. Enjoy the distance learning with Tinkercad!

For more project idea, visit DIY4 Pro.