Introduction: Knex Tower Crane

About: I love building. A mechanical engineering student, most of my instructables involve modeling projects, K'nex ball machines, and Lego creations. I am also a model railroader, and I enjoy science (astronomy is m…

My first large-scale knex project! This is a great Knex Tower Crane that is 6.2 feet tall and has a boom 4.11 feet long. Very durable, it has stood for two months in my room under all kinds of tests. (There is a limit to it's ability, though.) I hope you like it, the crane rotates and has a working hook. You can make your own hooks for various tasks.

Step 1: Piece Count

 With this large a project, piece counts are necessary!
Subject to small counting errors.


1-way grays: 58
oranges: 40 (68 if fully cross-braced)
reds: 20
greens: 4
snowflakes: 32
purple snaps: 222
blue snaps: 94


green: 80
white: 72
blue: 106
yellow: 73 (129 if fully cross-braced)
red: 147
gray: 68
black: 2


tires: a whole lot!
blue spacers: 20
gray spacers: 9
small blue gears: 2
medium yellow gears: 3
big yellow gears: 2
tan clips: 14
blue clips: 7
string: a reasonable amount, yarn works well

Step 2: Base and Tower

 Not hard, just follow the pics!

Step 3: The Gearbox

 This little rig makes the entire boom rotate with the turn of a crank!
I assume that it could be fitted with a motor if desired. I simply don't have one.

Step 4: Boom Base and Winch

 This connects the boom to the tower. Follow the pictures or the model won't work.

Step 5: Winch Casing

 This is for strength, but it also makes it realistic.

Step 6: Counterweight Bin and Connecting Beam

 This handy device will hold the counterweights to balance a load!

Step 7: The Hook

 This is my model for a hook, anything will work.

Step 8: The Boom

 This is what makes a tower crane a tower crane!

Step 9: Final Assembly, Part 1

 Connect it all, and have fun with your new awesome model!

Step 10: Final Assembly, Part 2

 Ok, now you're done!