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http://www.thingiverse.com/thing:1242762
Molecule Construction Kit by mfritz is licensed under the Creative Commons - Attribution license.
http://creativecommons.org/licenses/by/3.0/

# Summary

Use the pieces to build a model of a molecule.

Making models of molecules using ball and sticks or similar materials is a common middle school science activity. Now you can 3D print your molecule model.

Open the file Molecule Construction Kit on Tinkercad.com and you'll have all the parts you need. Or download the parts individually and put them together in your favorite cad program.

https://www.tinkercad.com/things/5QKJ0SWFHmN



# How I Designed This

The easiest way for students to build their molecule is to open the file Molecule Construction Kit on Tinkercad.com https://www.tinkercad.com/things/5QKJ0SWFHmN. All the parts are in that file and students just need to move them into the correct position and then delete the extra pieces.

Students will want to use the arrow keys to help them move parts into the correct position. They will not need to resize the pieces or lift them off the workplane. They can copy or duplicate to make extra copies of the organelles, and they can use rotate to change the direction of the bonds.

# Project: Build a Molecule

## Objective

Students will design and print a model of a molecule

## Audience

This project is intended for an 7th grade chemistry class but could be used for grades 6 - 8.

## Preparation

Students should have a basic understanding chemical bonds. Students should have a structural diagram of a model to work with so they aren't just putting pieces together in a random way. I included a PDF file with several famous molecules you can download and use.

The 3D design process using Tinkercad is relatively easy and would be a good project for beginners.


## Steps

1. Go to Tinkercad.com and find the Molecule Construction Kit file and open it https://www.tinkercad.com/things/5QKJ0SWFHmN
2. Assemble the parts to make your molecule
3. Use Copy or Duplicate to make extra copies of atoms and bonds. You can use rotate to change the angle of the bonds
4. Delete all the extra pieces
5. Print your molecule
Optional: You can use paint or markers to color the model

## Results

This project was completed as described with two 7th grade classes.  Students were able to complete molecule models in one class period (45 minutes).

Two most common problems 
1. Leaving small gaps between bonds and atoms so that they are not solidly connected. In Tinkercad the easiest way to check this is to view the model from below the workplane. In this orientation you can clearly see the overlap between the bonds and atoms.  It also helps to tell the students that the bonds should go to the middle of the atom, not to the edge.

2.  When rotating bonds and stretching them between atoms they will sometimes get too thin. Because Tinkercad's controls move shapes in X, Y, and Z directions it can be hard to widen a bond when it's on an angle. Easiest thing to do in that case is just delete it and duplicate a bond that's the proper thickness and move it into the correct position.