Origami Tank
I go online to look at other origami constructs a lot. I have found a decent number of impressive tank designs.
This is one of my own.
I came up with this one because 1: I thought it would be fun, and 2: every single tank I saw required a second piece of paper for the barrel, or the turret as a whole.
Supplies
Half of a square of paper (rectangular, not triangular), p
The Base
Start with your bicolored biece of paper, fold it in half, and use the crease to fold the sides inward (This will be used to get the 2-color look).
The Start of the Barrel
Flip the thing over and fold it in half. Fold it in half again as shown, and then fold it down as shown.
The Turret
Form a waterbomb base shape at the top. You should be able to form triangle-shaped creases at the top, and use those as guides.
Finishing Off the Head
Fold the main body of the turret back and forward as shown.
Squash fold the barrel so that it slims down. Fold the area under the barrel in a similar fashion, as shown.
Peel the flaps on the "head" back and behind the turret. Do a similar thing for the barrel (You may have to unfold a few things to accomplish this cleanly).
Slide the barrel backwards so it fits snugly into the outline of the head of the turret. Flatten the pockets that form. Then fit the barrel inside the body of the turret. Curl the edges of the head around the barrel as shown to lock it in place.
Barrel Done
Repeatedly fold the barrel as to narrow it.
The Wheels/treads
Fold the side bits to the middle as far as the paper will allow (It isn't very far in small models). Fold them in half up to the main body of the tank. Fold them as shown to slim them down.
Armor and Finishing Touches
Crease the body at the front and back to make it look more armored.
Feel free to crease the turret to give it varying shapes.
Note: wheel size is mainly affected by the thickness of paper used. If you can use thinner paper, you can make taller tanks!
Other note: you can use different lengths of paper!!! It just makes the barrel longer and the tank itself longer, the methods are the same =D