Friday 14 March 2014

Architecture: How to make a geodesic dome

We Have made a few Geodesic domes over the years, they always give a lot of pleasure to my little ones and make for a great cheap homemade den!

If you have never tried, I thoroughly recommend you give it give it a go. In this post I will give you step by step instructions on how you can build your own.

What is a geodesic dome?

A geodesic is defined to be a curve whose tangent vectors remain parallel if they are transported along it. The term, geodesic, comes from geodesy which is the maths and science used to measure the earth!

A geodesic dome is made purely of triangles, it is  a simple structure made using straight lines to create a curved structure.

For our Geodesic dome we are going to use newspaper, tape and staples.

First, to add to the fun and make it easier to construct, gather some friends or family members to help you.  It took us two people to make our one today.

You will need...

• Loads of newspapers
• scissors
• masking tape or any sticky tape you can find
• Stapler
• markers, felt tip pens, glitter, beads and glue (optional)

STEP ONE

First you will need to roll up lots and lots of newspapers.  You will need to use 4 sheets of newspaper a time and roll it up from one corner as tightly as possible.

TIP: It is VERY important to roll it super tight as it will give your rolled paper more strength.

When you reach the end of the newspaper, stick it in place with some form of sticky tape like this.  This is just so it doesn't unravel!

You will need 25 of them in total.

STEP TWO

Cut all the rolls of newspaper so they are the same length.  You want them to be as long as possible so don't hack too much off.

Ours were 65cm long each.

STEP THREE

If you have time and would like to make this project more arty you could decorate your paper sticks at this point with your felt tips, glitter, buttons or anything else you can think of. THIS MUST BE DONE BEFORE THE CONSTRUCTION OF THE DOME IF YOU ARE GOING TO DECORATE IT.

THE CONSTRUCTION

STEP FOUR

Make 5 triangles by sticking them together with tape and reinforcing them with a staple in each corner.

This will use 15 of your paper sticks.

STEP FIVE

Stick the bottom corners together.  Use the stapler to reinforce this so you have a star shape on the floor.

STEP SIX

You will need 5 more paper sticks for this step.

Tape a stick so one end is stuck to the top of one of the triangles on your star shape to the top of the next triangle.   We used a staple gun to reinforce the joints for this too.

If you are doing this right you will need a friend to hold it up as you go round because your dome will start to take shape already!

STEP SEVEN

You will need another 5 paper sticks, this will be the last sticks you have.

Tape a paper stick to the top of each of the triangles.  We used a staple gun to reinforce the joints again.

STEP EIGHT

Tape these loose sticks to the centre.  This completes your dome and you're ready to play!

How can you turn it into an experiment?

To turn this science and maths project into a science experiment all you have to do is make a prediction. You can do this by predicting how many magazines you think your newspaper dome will be able to support. Then trying it out!

You might like to test this now and see how many magazines or books (or if you've made a mini one coins) it can hold!

Here are a few more geodesic experiments...

What's the strongest dome you can make?

Why do you think the dome is as strong as it is?

Can you make the dome stronger?

Geodesic Geometry

Domes go back to Ancient times, people like the Ancient romans created huge domes using their knowledge of arches, these were heavy and not very strong.

Geodesic domes are different as they aren't just dome shaped, they are a curved shape made from straight lines - they are made out of triangles!

The reason triangles are so strong is because they have fixed angles  that do not distort - they don't change shape - very easily.

Triangles are the strongest of all shapes!  Why?

If you apply pressure to an edge of a triangle the force you put on it is equally distributed to the other two sides of the triangle, this pressure is then transferred to the other triangles adjacent.  The stress is shared by the whole structure just like the structure of an egg!

Richard Buckminster Fuller was the man that invented the geodesic dome.

Maths in this project

Geometry
Measuring
Shape
Tessellations

Science covered
Forces
Structures
Architecture