Lego Lazy River: Making Water Move

Introduction: Lego Lazy River: Making Water Move

There are many techniques for adding water (lakes, ocean, rivers) to your lego project. But, what if you want the water to move? What if it needs to move in a circle (lazy river)? This Instructable shows how to move lego parts to simulate moving water. It also goes into detail on how to set up the gears so you get the circular motion. Most importantly it describes the purpose of each gear in the project. There are two options for creating the project: manual control (see image 2) and motor control (see image 3).


Base- I used Medium blue

3 - 16x32 base plate

6 - 2x16 plate

1 - 2x10 plate

1 - 2x3 plate

2 - 2x2 plates

1 - 1x6 plate

5 - 1x4 plate

4 - 1x2 plate

Gear Structure - any color

32 - 1x16 Technic. bricks

4 - 1x14 Technic bricks

1 - 1x10 plate

1 - 1x4 plate

2 - 1x4 brick

1 - 1x6 brick

Gears/axles - any color

26 - Technic bush

15 - Technic bush ½ Smooth

8 - axle 12

1 - axle 6

4 - axle 5

80 - Technic liftarm Thin 1x3 Axle Holes

2 - Technic gear 40 Tooth

2 - Technic, gear 24 Tooth Crown

1 - Technic knob gear

12 - Technic gear 24 tooth

1 - Technic, axle connector 2L

Moving Water - unless specified any color

2 - 1x2 trans light blue plate

128 - plate round 2x2 with rounded bottom

4 - net, string 8x16 rectangle

512 - 1x1plate round (mostly trans light blue with some trans clear)

Fill in Water

4 - 2x16 plate medium blue

112 - 1x1 plate round (mostly trans light blue with some trans clear)

4 - 1x4 tile (white)

Pool - I choose white

2 - 1x16 brick

15 - 1x12 brick

17 - 1x8 brick

7 - 1x6 brick

10 - 1x4 brick

47 - 1x3 brick

17 - 1x2 brick

2 - 2x2 corner brick

3 - 1x1 brick

3 - 1x2 plate

Decking and Supports

3 - 2x16 plate medium blue

1 - 2x3 plate blue

3 - 2x3 plate white

1 - 2x4 plate blue

3 - 2x4 plate white

5 - 2x6 plate white

5 - 2x8 plate white

7 - 2x10 plate white

3 - 1x2 plate white

1 - 1x10 plate white

3 - 1x12 plate white

1 - 4x4 plate blue

1 - 1x2 brick white

5 - 1x3 brick white

2 - 1x4 brick medium blue

8 - 1x12 brick medium blue

9 - 2x2 brick white

7 - 2x3 brick white

4 - 2x4 brick white

5 - 1x2 tile white

1 - 1x3 tile white

5 - 1x4 tile white

22 - 1x6 tile white

2 - 1x8 tile white

22 - 2x2 tile white

7 - 2x4 tile white

Planters (3) and Lounge Area

2 - plant prickly bush 2x2x4 green (any shade)

4 - plant flower stem green (any shade)

3 - plant plate round 1x1 with 3 leaves green (any shade)

4 - plant brick round 1x1 with 3 bamboo leaves green (any shade)

2 - plant leaves 4x3 olive green

6 - plant leaves 4x3 dark red

7 - plant leaves 4x3 bright green

2 - plant leaves 4x3 lavender

1 - barb - large flexible reddish brown

1 - 4x12 plate white

2 - 1x4 plate white

1 - 2x2 plate dark tan

1 - 2x12 plate dark tan

2 - 2x16 plate dark tan

2 - 4x6 plate dark tan

1 - 6x8 plate dark bluish gray

1 - 6x10 plate dark bluish gray

2 - 1x2 brick tan

4 - 1x2 brick medium nougat

16 - 1x4 brick tan

2 - 1x16 brick reddish brown

5 - 2x2 brick round with flutes reddish brown

8 - 1x1 brick round reddish brown

1 - tile round 2x2 with open stud dark bluish gray

2 - 1x2 tile blue

1 - 1x2 tile medium blue

2 - 1x3 tile white

2 - 1x4 tile white

2 - 1x6 tile white

1 - 1x8 tile white

3 - 2x2 tile white

1 - 2x2 tile medium blue

2 - 2x2 tile blue

3 - 2x4 tile white

12 - 1x1 plate round light bluish gray

15 - 1x1 plate round with open stud reddish brown

8 - plate round 1x1 with flower edges - various colors

1 - plant leaves 2x2 with 4 petals and axle hole medium azure

1 - bar 6L with stop ring black

2 - arch 1x3x3 reddish brown

3 - arch 1x3x2 medium nougat

6 - 1x2 plate modified with clip on end (horizontal grip) white

8 - 1x2 plate modified with clip on end (horizontal grip) reddish brown

3 - 1x2 plate modified with 2 open O clips (horizontal grip - medium nougat

4 - plate, modified 1x2 with bar handle on end - closed reddish brown

10 - plate round 1x1 bar handle on side - reddish brown

3 - plate modified 1x2 with bar handle on side black

Extras for Motor Control

1 - 16x32 base plate

2 - 2x4 bricks

1 - Lego Medium Motor

1 - Lego Battery Pack

Step 1: Setting Up the Base

1) Position three 16x32 baseplates for the entire lazy river area (see image 1).

2) Secure the three baseplates together (see image 2).

3) Add additional plates (see images 3 and 4). These will be important later when building the structure for the project.

4) Secure one additional baseplate (see image 4) if you plan to use a motor to control the movement.

Step 2: Assembling the Mechanics

Steps 2 and 3 are the most important steps of the project. Once these two steps are completed, you can design your own lazy river (although I do show you how I completed my lazy river).

1) Attach ten 1x3 technic liftarm thin to an axle (12L) alternating the blades from one side to the other (see image 1). Repeat seven more times. There are four sections to this setup with two axles for each section.

2) Build eight walls with each consisting of four 1x10 technic bricks, one 1x10 brick, and one 1x10 plate (see image 2).

3) Position the eight walls as shown in image 3 (there are 8 studs between parallel walls). This sets up the four sections: bottom, top, right, and left.

4) Build one more wall (it can be 1x16 or 1x14) and position it as shown in image 4.

5) Image 5 shows the controlling gears and axles. The power (hand or motor) is attached to the smaller middle gear. The two larger gears rotate the two axles with technic liftarms for the bottom section. The reason for three gears instead of two is twofold. First, the middle gear ensures that the two larger gears rotate in the same direction. Second, going for a small gear to larger gears produces more power and less speed which is needed for a lazy river.

6) There are five gears in the middle of the lazy river. Two gears (numbers 3 and 5 from the left) are connected to the axles from Step 5 (bottom section). Two gears (number 2 and 4 from the left) are connected to axles on the top section. The fifth gear (number 1 from the left) simply allows the gear train to reach the section on the left. The reason for not using the same axles for the bottom and top sections is that the axles need to rotate in opposite directions so that the water moves in a circular motion (see image 6).

7) Image 7 shows the left section of the mechanism with a crown gear (used to change the direction of the motion) and three additional gears. Again, the middle gear is used to control the rotation direction of the two outer gears so that they rotate in the same direction.

8) Image 8 shows the same set up as in step 7 but for the right section of the mechanism. Image 9 shows the complete set up from the top section view.

9) Image 10 shows the addition of an axle and knob gear used to turn the gears. The video in image 11 shows the movement in action.

10) Image 12 shows replacing the knob gear with a Lego medium motor and battery for motor control.

Step 3: Creating Moving Water

This moving water technique uses a lego net, 2x2 round plates with rounded bottoms, and 1x1 trans round plates (see images 1 and 2).

1) Position the 2x2 round plates with rounded bottom so that the four studs protrude through the net (see image 2).

2) Attach four 1x1 round plates to each 2x2 round plate (see images 3 and 4).

3) Repeat for three more nets (see image 5).

4) One net is placed on top of each section.

Step 4: Forming the Pool

1) Build the perimeter of the pool (five bricks high) using white bricks (see images 1 and 2).

Step 5: Filling in the Water

In this step additional water is built to cover parts not covered by the moving water.

1) Attach 1x1 trans round plates to four 2x16 plates (as shown in image 1).

2) Connect two of the 2x16 plates using white 1x4 tiles (as shown in image 2). Repeat for the other two 2x16 plates.

3) Image 3 shows how the fill-in water looks on both sides of the plates.

Step 6: Constructing the Decking

Build a deck on top of the pool's perimeter.

1) Add plates (1x, 2x) over the bricks (see images 1 and 3).

2) Add white tiles over the plates (see images 2 and 3)

Step 7: Building the Raised Deck Area

I choose to have a raised deck area for lounge chairs and an umbrella on one side of the pool.

1) Position two gray plates (6x8 and 6x10) together. Lay a white plate (4x14) on top (see images 1 and 2).

2) Position white tiles on the remaining gray area (see image 3).

3) Create three lounge chairs following images 4 and 5.

4) Create an umbrella following images 6 and 7.

5) Position the lounge chairs/umbrella on the deck and position the deck as shown in image 8.

Step 8: Decorating the Pool Area

The last step is to decorate the pool area with three plant boxes.

1) Build the main plant box (for the center of the lazy river) following images 1 through 4.

2) Fill in the main plant box following images 5 through 9.

3) Build and fill in one small plant box following images 10 and 11.

4) Build and fill a second small plant box following images 12 and 13.

5) Position the three plant boxes as shown in image 14.

6) Image 15 is a video which shows the water moving in a circular motion.

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