IPhone 4 Case With Earphone Winder in Autodesk 123D

Somehow, whenever you put your earphones into your pocket, they manage to get themselves tangled. It is far too annoying to have to untie the knot they put themselves in every time you reach for them. With this Instructable, you can learn to make an iPhone 4 case in Autodesk 123D that can solve this problem for you. Each screenshot shows what your screen should look like after the end of each paragraph. There is a .stl below of a plain iPhone 4 case so that, if you wish, you may cut ahead to the last step.

Step 1: Making the Outline of a Case

This Instructable uses the iPhone 4 GSM Dimensional Drawing from page 16 of the Case Design Guidelines for Apple Devices available for free at https://developer.apple.com/resources/cases/Case-Design-Guidelines.pdf.

To start, open up a new file in Autodesk 123D Design. Create a new sketch by mousing over the “Sketch” menu and clicking “Rectangle.” Click the grid shown on start up to select that plane for the new sketch. To specify the first corner of the rectangle, click on the black and white circle. The dimensions for this rectangle are 58.55mm and 115.15mm.

Click anywhere to create the rectangle. It will turn yellow to show that it is a closed shape. Next, under the “Construct” menu, click “Extrude.” Type 9.34mm into the dialog box and press the “Enter” key.

In the “Modify” menu, click “Fillet.” Select the four vertical edges created by the extrusion. In the dialog box, type 8.77mm. Press the “Enter” key.

In the “Modify” menu, click “Shell.” Select the top face of the object (where the screen would be). On the far right of the dialog box, click the drop-down menu and select “Outside” instead of the default “Inside.” In the “Thickness outside” textfield, type 1.5mm for the thickness of the case. Press the “Enter” key.

You now have the basic outline of an iPhone 4 case. Next, we have to create holes for the charging port, speakers, camera, volume buttons and ringer, sleep/wake button, earphone port, and antenna.

Step 2: Making a Cutout for the Charging Port and Speakers

Rotate the view-cube in the upper right to let you look at one of the smaller sides of the case. This side will be where the end of the phone with the speakers and charging port will sit. Under the “Sketch” menu, click “Project” (the rightmost item).  Select the chosen side for the new sketch, and click the bottom of the inside of the case (where the iPhone ‘s back will sit), the flat piece of the interior of the left side of the case (where the iPhone’s ringer and volume buttons will be) and the flat piece of the interior of the right side of the case. Press “Enter.” In the “Sketch” menu, click “Polyline” and select one of the points on the lines created with the “Project” command to edit that sketch. Select the upper right point and move the mouse overt to the upper left point to make a rectangle. Next, select the upper left point again. This time, press the “Tab” key so that you can enter 45 into the dialog box that sets the line’s angle. Press “Tab” again so that there is now a lock symbol on the angle dialog box and move the cursor so that the new line intersects the bottom line created with “Project.” There a small “X” will appear at the intersection when you do this. When the “X” appears, click. Do the same for the point on the upper right, except the angle will now be 135.

Now, under “Construct,” click “Extrude.” Select the trapezoid formed in the last sketch and in the dialog box, type -25mm into the dialog box. Make sure that the distance between the sketch and the position the extrusion will stop at is red, meaning that the extrusion will subtract from the case, not add to it. If it is adding to it, click on the drop-down menu on the right of the dialog box and click “Cut.” Press “Enter.”

Step 3: Making a Cutout for the Ringer and Volume Buttons

Next, we’ll create a hole for the ringer and volume buttons. Rotate the view-cube to the side of the case where these would be on an iPhone. Under the “Sketch” menu, click “Project” and select the outside of the aforementioned side of the case for the new sketch. Then, project the flat part of the inside of the side of the case where the sleep/wake button would be and the part of the case the iPhone’s back will touch.

Under “Sketch,” click “Polyline” and select the upper point of the only vertical line we created with the “Project.” Move the mouse to the right and type 9.17mm into the dialog box, making sure that the line is completely horizontal and click, then, move the cursor straight down, making sure the line stays completely vertical and type 1.27mm into the dialog box and click. Move the cursor to the right, keeping the line completely horizontal and type 38.92 into the dialog box and click. Move the cursor straight down, keeping the line completely vertical and type 6.8mm into the dialog box and click. Move the cursor to the left keeping the line completely horizontal and type 38.92mm and click. Move the cursor up keeping the line completely vertical and type 6.8mm and click to complete the rectangle.

Under “Construct,” click “Extrude” and select the rectangle you just created. Type -25mm into the dialog box, making sure that the extrusion subtracts from the case. Press "Enter"

Step 4: Making a Cutout for the Sleep/wake Button, Antenna, and Headphone Jack

The previous sketches were deleted to start this step. You may choose to do the same.

Rotate the view-cube to the left to the other small side, where the sleep/wake button side of the iPhone will be. Under “Sketch,” click “Project” and select the aforementioned side. Then, select the same face again and then the part of the case the back of the iPhone will touch.

Under “Construct,” click “Extrude” and select the upper of the two rectangles (it is also the largest in area). In the dialog box, type -25mm and make sure it is subtracting from the case. Press “Enter.”

Step 5: Making a Cutout for the Camera

Rotate the view-cube so that you can see the bottom of the case. Under “Sketch,” click “Project” and then select the bottom of the case for the sketch. Click the piece of the case that the iPhone’s back will touch.

Under “Sketch,” click “Circle” and select the point on the corner with the camera that was created when we filleted the edge before doing our shell. In the dialog box, type in a diameter of 16mm and click. Under “Sketch,” select “Polyline” and select the sketch you just created and mouse over the aforementioned point. Slowly move the cursor upwards from that point so that a dotted line appears. When that line meets the circle you just created with a small “X” click and move the cursor to the right, keeping the line completely horizontal and type 3.75mm in the dialog box and click. Move the cursor down keeping the line completely vertical and type 16mm in the dialog box and click. Move the cursor to the left keeping the line completely horizontal and type 3.75mm into the dialog box and click. Under “Sketch,” click “Circle” and select the sketch you just created and move the cursor over to the middle of the only vertical line created with that “Polyline.” When you see a small triangle appear, click (you may have to zoom in). In the dialog box, type 16mm for the diameter and click.

Under “Construct,” select “Extrude” and click on every piece of the camera cutout you just created (there should be 8 pieces). In the dialog box, type -25mm and make sure it is subtracting from the case. Press “Enter.”

We now have a basic iPhone 4 case. We will add a winder on the side of the case so that you can keep your headphones from getting tangled while not in use.

Step 6: Making the Earphone Winder

Rotate the view-cube so that you can see the only side of the case without a hole in it. Under “Sketch,” select “Project” and click on the flat portion of that side, click on the face again so that you project a rectangle onto the sketch. Under “Sketch,” select “Offset” and click on the same sketch as before. Click on the rectangle you just projected and type 4mm into the dialog box and press “Enter.”

Under “Construct,” select “Extrude” and click on the inner rectangle from the last sketch. Type 8mm into the dialog box and press “Enter.”

Under “Sketch,” select “Project” and click on the extruded face. Then, click on the rectangle you projected in the last sketch.

Under “Construct,” select “Extrude” and click on the rectangle you just added to the last sketch. Type -1.5mm into the dialog box and press “Enter.”

Feel free to fillet some of the edges to achieve a smoother look and feel. You may now 3D print this design and attach it to your iPhone 4. When you’re finished using your headphones, just take the end not plugged into the phone and wrap it around the winder on the side. Leave some slack between the headphone jack and the winder so as not to damage the headphones or the phone.