Return To Build

Build

Basic Mechanisms

Print

Piston

Steps 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Step 1

Servos rotate in a circle, but the piston mechanism can be used to transform this rotation into movement back and forth along a straight line.

Popular uses of the piston include flapping wings and jumping characters. What will you create?

Step 2

Hardware

  • Hummingbird Controller (Bit Controller pictured. The Duo controller will also work)
  • Battery Pack or AC Plug
  • Position Servo (Your servo may look different)
  • Circle Servo Horn

Suggested Craft Supplies

  • Hot Glue Gun
  • Heavy Duty Hole Punch
  • Scissors
  • Blade
  • Marker
  • 3 Jumbo Craft Sticks
  • 2 Brass Brads
  • Scrap Cardboard
  • Cardboard Box with Flaps (For beginners, we have found the 6x6x6 box works best)
Step 3

Interlock the tabs on one side of the box.

Step 4

Place your servo on the corner of the cardboard box, opposite the box’s opening. The servo should be about 2.5cm from the edges of the cardboard box. Trace around the servo using a marker.

Step 5

Use the blade to cut out a rectangular hole for the servo. Be sure to cut inside the line. This will ensure that the servo has a nice, snug fit.

Step 6

Starting inside the box, push the base of the servo through the hole until it is secured. If the hole was cut too large, a dab of hot glue may help to keep the servo in place.

Set the box aside. You will not need it for the next few steps.

Step 7

Cut off a section of scrap cardboard that is about 8 cm x 4 cm.

Use the jumbo craft stick as a straight edge to draw a line that is about 2 cm long and 1.5 cm from the edge.

Use the scissors to cut out the line. This will make a slot in the cardboard.

Set the slotted cardboard piece to the side.

Step 8

Use the marker to label the 3 jumbo craft sticks 1, 2, and 3.

Make the following marks on the jumbo craft sticks:

Craft stick #1 – Make a dot directly in the center and a line 3/4 of the way up the craft stick.

Craft stick #2 – Make a dot about 1 cm from the bottom and a second dot 3/4 of the way up the craft stick.

Craft stick #3 – Make a dot about 1 cm from the top

Step 9

Use scissors to cut along the line on craft stick #1.

Step 10

Use the heavy duty hole punch to make a hole over every dot.

Step 11

Find the circular servo horn.

Glue the servo horn to the bottom of craft stick #1. Try not to get hot glue into the center hole of the servo horn.

Step 12

Use a brass brad to attach craft stick #1 to the hole 3/4 of the way up craft stick #2. Use the other brass brad to attach craft stick #3 to the hole 1 cm from the base of craft stick #2.

Step 13

Apply glue along the bottom edge and right edge of the slotted section of cardboard. Be careful not to get glue in the slot. Adhere the slotted cardboard to the inside edge of the box.

Step 14

Feed craft stick #3 through the slot and push the servo horn onto the servo shaft.

Need help getting started? Select your desired programming language and device from this page.

Step 15

Note: Depending on a range of factors (size of the box, placement of holes, angle of servo) your piston may jam. It may be necessary to install a small stopper.