Model Sailboat With a Self Trimming Sail - Educational

Introduction

I teach beginner sailing and designed this model to help my students understand the points of sail. The orientation of the wind, sails, and hull define a boat's point of sail. Unfortunately, many of my students struggle with this concept. They are often slowed down by jargon, and the core message gets lost. This model is designed to skip the jargon and teach sail trim kinesthetically in the palm of your hand.

The model orients the wind, sails and hull to each other using a gear box. They are mechanically interlocked such that the sail is always correctly trimmed. A dial indictor reads out the current point of sail of the boat. Note that the wind arrow is pointing from True Wind and not Apparent Wind.

If you'd like to learn more about how I designed this you can read about it on my personal website.

Printing

Some printers struggle with the print-in-place gearbox because it has a part offset of only .01 inches (0.25 mm). If you have a budget printer, you may need to get your settings dialed in first.

I only used layer-based color changes, so results like in the image can be made without a multy-color 3D printer.

Supports are required on the Sail and Wind Arrow. Supports aren't required on the other parts.

Assembly 

Glue is required. I recommend Gel Super Glue.

1. Before assembly, check that you have all the parts. Make sure you have removed all support material and that the gearbox rotates freely.
   

   

   
    

2. Place glue on the magenta-colored surface 🟪, then insert the Points of Sail plaque into the boat hull.
   

   

   
    

3. Place glue on the magenta-colored surface 🟪. Align the blue-colored surfaces 🟦 and then push the gearbox into the wind arrow. Keep the gear teeth free from glue.
   

   

   
    

4. Turn the gearbox until the blue-colored 🟦 features align along the blue line 🟦. Note that any one of the 4 little gears can be used, they're identical.
   

   

   
    

5. Place glue on the magenta-colored surface 🟪. With the gearbox aligned from the previous step, press it into the boat hull.
   

   

   
    

6. Check that the wind arrow can swing between the blue lines 🟦, and no further.
   

   

   
    

7. Place glue on the magenta-colored surface 🟪, then press the sail and carrier together. Tip: allow the glue to dry before proceeding to the next step.
   

   

   
    

8. Orient the sail so it points aft, and rotate the wind arrow to the forward-most position. Next, press the sail/carrier into the gearbox. The prongs will clip into the gearbox once they've passed all the way though.
   

   

   
    

9. Assembly is finished! Be sure the glue is fully dry before use, this may take several hours. Tip: Reduce superglue ‘bloom’ under the hull by propping the bow up on a pen or small object.
   

   

   
    

Variations

I've made a few other versions of this model that I've uploaded as Remixes.

1. This version has no English text, allowing you to add your own language. 

2. This version is on the opposite tack (port tack). 

3. This version has the mast and sail separated into two parts for easy multiple color/material printing.

Have Fun!
My students found this to be a fun and interesting addition to their sailing class. I hope it works for you too.