Introduction: Geodesic Dome With Straws
In this tutorial I will show how to make a geodesic dome (v2) using only
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Overview and Needed Materials
To build this dome you will need:
1) 65 regular straws
2) 65 small zip tie
3) two parts epoxi resin (epoxi mass)
See the attached photos where I show the materials
We will need to build:
10 pieces of 6 arms conector
10 pieces of 4 arms conector
6 pieces of 5 arms conector
All these conectors will be made using the
zip ties (cutting the head off) and
they will be held together with the epoxi mass
The straw length is 24.5 cm (9.64 pol)
We will need 35 straws with that length
and they will be called "A" (blue color in the mounting diagram)
We will also need 30 straws cutted with 21 cm of length (8.26 pol)
They will be called "B" (red color in the mounting diagram)
In my pictures I used only white straws, the cutted ones, to make it easy to see them.
Step 2: Conectors Close Up
Here I show how the assembled conectors look like.
The 6 arms connector is made with
three zip tie crossed one above the other
They are held in place with a bit of two parts epoxi mass. (I supose hot glue can do the job but it is more messy)
The 4 arms connector uses two zip tie.
This time one zip tie is bended to from a 90 degrees angle. It is held this way with glue tape and than fixed with the other zip tie with epoxi. When the epoxi is cured you can remove the glue tape from the bent zip tie.
The epoxi will now held it bended 90 degrees
The 5 arms connector needs to be built with 5 half zip tie
Take 5 zip tie and cut them in half
You will end up with 10 half size zip ties.
Now using 5 of these mount one
5 arms conector.
See the picture above to understand how.
Step 3: Overview Before Assembly
Here I show an overview of the material just before assembly.
Pay attention that the white straws in the center of photo are the ones cutted
I am not showing all the 65 straws here but just the ones needed to build the base of the dome.
I am also showing a mounting diagram
One more time
"A" straws are 24.5 cm long (9.64 inches)
"B" straws are 21 cm long (8.26 inches)
Step 4: Mounting the Base
Lay down 10 long "A" straws and connect them to form a circle as seen in the photo above. Use the 4 arms connectors to connect the straws
Step 5: More Mounting
After the circle of straws is all connected.
We need to connect the straws that will support the first "floor" of the dome.
As per the mounting diagram of the previous step, the straws are conected in a "A"-"A" and "B"-"B" mode
The A-A straws will meet in the top to make a triangle pointing up
The B-B too will meet in the top.
Step 6: Connecting the First Floor
Where two A straws meet on top you should add a 6 arms connector
Where two B straws meet on top you should add a 5 arms connector
On last photo above you can clearly ser that on the B-B straws a 5 arms connector is placed and on the AA straws a 6 arm connector is placed.
I mounted the dome alone and needed to use the chair and the rubber seen in the picture to held the straws in place.
Now using only "B" straws horizontally link the connectors of the first floor one to the other to finish first floor.
Step 7: Preparing the Second Floor
On they previous stage we mounted all the first floor of the geodesic dome.
Now on each 5 arms connector we will have one empty arm point straight up.
We need to insert a "B" straw there
On each 6 arm conector we need to insert two "A" straws pointing up to give support to the next floor of the dome.
Step 8: Linking the Second Floor
After we finish last step we will have several straws pointing up.
They will support the second floor of the dome.
We join these "pointing up" straws using only 6 arms connectors.
Than we link this floor horizontally using this time only "A" (long) straws.
Step 9: Closing the Top
Second floor is concluded.
We will have one empty arm pointing toward the center (and top) of the dome.
We will insert 5 "B" straws on them.
All these straws will meet in the top where the last 5 arms connector will join them together finishing the dome.
CONGRATULATIONS you dome is now concluded
If you used auxiliary support to held the straws while mounting the dome you can now withdraw them cause the dome ready does not need any auxiliary support to held it in place