The following information is a single lesson in a larger Tinkercad project. Check out this and more projects on Tinkercad.

Lesson Overview:

Now we're going to make a balloon connector!

## Step 1: Create the Balloon Connector

In this lesson it will be important to know what size balloon are available for this project.

As we create the connector you will want to make sure you adjust sizes to make sure the connector works with the balloons you will be using for your car.

The opening in the balloons I am using are 18mm, so I am making the connector stem 20mm with a 3mm lip to hold the balloon on the car.

Instructions

1. Place a cylinder on the workplane and size it to 20mm in diameter and 10mm tall.
2. Place a second cylinder on the workplane and size it to 23mm in diameter and 3mm tall.
3. Select both cylinders and align them vertically, then align them to the top.
4. With both cylinders selected group them into a single object.
5. Continue to the next step.

## Step 2: Add and Angle Under the Lip

If we were to print the balloon connector part now, with out the purple shape shown in the image below, we would run into a problem with the 3D print.

Because of the overhang on the lip you will find that the plastic will droop or the print will fail unless you add support for the lip.

In order to help with 3D printing we will add a small angle (using an upside down cone) to the bottom side of the balloon connector lip.

This will allow the print to continue and slowly expand to the diameter of the lip.

Tip: If you wanted to print your connector upside down on your printer, you can skip this step.

Instructions

1. Place a cone shape on the workplane and size it to 23mm in diameter and 7mm tall.
2. Rotate the shape 180° so the flat surface is facing upwards.
3. Select both shapes and align them vertically.
4. With both shapes selected group them into a single item.
5. Continue to the next step.

## Step 3: Create a Hole in the Connector

The last step before positioning the connector on the car is to create an opening in the connector for the air to pass through.

We will make the hole in the connector larger than the path in the car just in case the path isn't aligned just perfectly.

Instructions

1. Place a cylinder on the workplane and size it to 15mm in diameter and 15mm tall.
2. Change the cylinder to hole.
3. Select both shapes and align them vertically.
4. Group both shapes into a single item to cut the hole through the connector.
5. Continue to the next step.

## Step 4: 3D Print Your Balloon Connector

We are now ready to export your balloon connector for 3D printing.

Instructions

2. Select .STL as the download format. The .STL file format can be used with any 3D printer.
3. Import the .STL file into your 3D printer software and print.
4. Continue to the next lesson.

In the next lesson you will learn to add wheels and axles!

Next Lesson:Create the Wheels and Axles