DofTNet Balloons

Cutting the trash bags

This design takes ten and a half trash bags. The following will show how DofT cuts the various shapes. Once you have your shapes you can attach them together using tape (easy but adds weight) or by heat sealing the edges together - see the next page. Use the image on the previous page as a guide on how the peices go together.


Get your bags 01

So you have 11 trash bags. Unroll them but don't completely unfold them yet.

Cut off the bottom 02

So you'll probably notice that one end has been sealed. That's gonna get in the way so you should really just cut that end off.

Now unfold 03

Now unfold it. It's essentially a tube at this point. You'll wanna do this with all of them.

Make the top 04

You'll need to do this with two of your bags. First, fold it in half the long way - perpendicular to the open ends.

Cut diagonally 05

Cut through all layers of your folded bag diagonally from one corner to the opposite corner.

Top Panels 06

Once you've finished cutting you should end up with four panels shaped thusly. Once you've done this with your second bag, you should have a total of 8 sheets shaped like this

Make the sides 07

The sides are pretty easy. Just cut a single layer along the edge. Follow the crease as a guide. Do this with four bags.

Your side panels 08

Once you've cut along the side and finished unfolding it, you should have a nice simple rectangle.

Start the neck 09

The next set of panels are smaller bits that will taper the main envlope down towards the bottom. You'll need to do this with 2 bags. First, cut them in half parallel to the open ends of the tube. If it makes it easier, fold it in half and cut along the crease

Fold in half 10

Fold the resulting half-bags in half perpendicular to the open ends. Follow an existing crease if one exists. You can try this with both halves at once or just one half at a time.

Cut the sides 11

Cut all layers from one corner to the middle of the opposite open end. The smaller bits are not used.

Trapazoids! 12

One half bag gets you two panels like this. Once you complete both halves of both bags, you'll have a total of 8 panels this shape and size.

The main neck 13

Take two more bags, fold in half perpendicular to the open ends again.

Cut the sides 14

Similar to the last set of peices, cut from one corner to the middle of the opposite end.

Tall Trapezoid 15

Each bag will get you two panels shaped like this - a tall trapezoid or... a long sideways trapezoid? Either way, you'll need a total of four.

The Opening 16

The bottom part of the neck can be a half bag. It could be a full bag too but that gives it a really long neck which looks kinda weird to DofT so he sticks with the short neck.