Let's Begin
10 minutes
1. Warm-Up: Recap the Sandbox
Before we start the ship, let's review what you built last week. Open your Turtle Sandbox model.
Quick review:
- Orbit around your sandbox
- Check that all four walls are the same height
- Confirm that all parts are connected (no floating walls)
- Point out where you used Offset and where you used Push/Pull
The same skills you used for the sandbox will be used for the ship — just on a larger scale.
Reminder: Save your work with the format week#-studentid-firstname-lastname.
15 minutes
2. Ship Shape: Base Rectangle + Triangles
Pirate ships have a pointed front (the bow) and a flatter back (the stern). To make this shape, we'll start with a rectangle, then add triangles to the ends.
Step 1: Draw the main body
- Select the Rectangle tool (R)
- Draw a rectangle — type
4m, 1.5m — press Enter
- This is the main body of the hull
Step 2: Draw the bow (front triangle)
- Select the Line tool (L)
- Draw a line from the top-left corner going forward
- Draw a line from the bottom-left corner meeting the first line
- This creates a triangle — the pointed front of the ship
Step 3: Draw the stern (back triangle)
- Repeat the same steps on the right side
- Draw a triangle extending from the right edge
- This creates the back of the ship
Step 4: Clean up
- Select the Eraser tool (E)
- Remove the lines where the rectangle and triangles overlap
- You should now have one continuous pointed shape — the top view of a ship
Inference lines are your friend. When drawing, SketchUp shows green, red, and blue hint lines that help you align to edges and endpoints.
20 minutes
3. The Hull: Offset + Move
Now we'll give the hull shape its depth. The hull is the curved body of the ship — its outer and inner walls.
Step 1: Extrude the hull upward
- Select Push/Pull (P)
- Click the flat ship shape
- Pull it up — type
1m — press Enter
- You now have a tall block in the shape of a ship
Step 2: Create the inner hull with Offset
- Select the Offset tool (F)
- Click on the top edge of the hull
- Move inward and type
20cm — press Enter
- You now have an inner shape that follows the ship's outline
Step 3: Push down the inner hull
- Select Push/Pull
- Click the inner top face
- Push it downward — but do NOT go all the way through
- Stop about
20cm from the bottom
- This creates the "cup" shape — the inside of the hull
Step 4: Use Move to fine-tune
- Select the Move tool (M)
- Practice moving parts of the hull up and down
- Press Ctrl + Z to undo if something goes wrong
Don't push through the bottom! If you push the inner hull all the way through, it creates a hole. Undo and try again.
20 minutes
4. The Deck: Offset + Push/Pull
The deck is the flat floor of the ship — where pirates walk. It sits on top of the hull, inside the walls.
Step 1: Draw the deck
- Select the Rectangle tool
- Draw a rectangle that fits inside the hull
- Or use Offset again to create the exact shape
Step 2: Give the deck thickness
- Select Push/Pull
- Pull it up slightly — type
10cm
- This is the deck's thickness
Step 3: Position the deck with Move
- Select the deck (use Select tool — spacebar)
- Right-click → Group
- Select Move tool (M)
- Move the deck down into the hull
- It should rest about
20cm below the top of the hull walls
Step 4: Copy the deck (optional)
- With the deck selected, press Ctrl + C then Ctrl + V
- Use Move to place the copy as a lower deck
- Real pirate ships often have multiple decks!
Move + Copy shortcut: Select the object, press M, then hold Ctrl while moving. This copies instead of moves.
25 minutes
5. Build Hull + Deck (Your Turn)
Now it's your turn to build the hull and deck. Follow the same steps, but make it your own ship.
Required features:
- A pointed front (bow) and back (stern)
- A hull with walls and a hollow inside
- A deck positioned inside the hull
- All parts connected — no floating pieces
Suggested dimensions:
| Part |
Suggested Size |
| Hull length | 5m |
| Hull width | 2m |
| Hull height | 1.2m |
| Hull wall thickness | 20cm |
| Deck thickness | 10cm |
| Deck depth below rim | 20cm |
Optional extras (if you have time):
- Add a curved front by pushing/pulling the bow inward
- Add a second lower deck
- Add a small staircase using the Line tool
Save often. Press Ctrl + S after every major step. You don't want to lose 25 minutes of work.
10 minutes
6. Check for "Solid Group"
A solid group is a 3D object that is completely closed — like a watertight container. Only solid groups can be 3D printed.
What is a solid group?
- Every edge is shared by exactly 2 faces
- There are no gaps, holes, or open faces
- It's the equivalent of a sealed box
How to check your model:
- Select your entire model (drag a box around it with the Select tool)
- Right-click → Group
- Look at the Entity Info panel on the right
- It should say "Solid Group"
- If it just says "Group" — your model has holes or open faces
How to fix a non-solid group:
- Use the Eraser tool to remove stray lines
- Use Line tool to close any gaps
- Look for inside-out faces (they appear dark gray/blue)
- Right-click a bad face → Reverse Faces
Save your work:
- Click the model name at the top
- Rename it:
week4-studentid-firstname-lastname
- Click Save
- Verify it appears in your Google Drive
Don't worry if it's not perfect yet. Solid geometry is tricky. We'll keep working on it in Week 5 when we add the cabin and portholes.