Cardboard builds

Cardboard Arcade Button

Build a large springy push button that closes a foil contact and can trigger a low-voltage game input or continuity test.

A big arcade button is really a controlled moving platform and a switch. Cardboard guides the press, folded springs return it, and two foil pads meet only at the bottom of travel.

Three-button controller demonstrating the same press-to-switch idea. The cardboard version in this guide uses a different enclosure and contact system.Image supplied by the site owner.

Difficulty: Beginner
Build time: 35-55 min
Estimated cost: $0-$5
Age range: 10-16
Workspace: A clear table about 90 cm wide

The finish line

What you will build

The button presses at least 8 mm, returns after release, and closes the low-voltage contact on nine of ten deliberate presses without staying stuck.

Learning goals

Identify how downward hand press on the cap produces momentary low-voltage electrical contact.
Construct and explain a linear press-to-binary switch state system.
Measure how the folded-spring height changes performance.
Diagnose losses caused by guide rubbing and spring fatigue.

Before you build

Materials, tools, and safety

Reuse-material cost: $0-$3 with reused materials. Supervision: Adult help recommended for sharp or heated tools.

2-4 × corrugated cardboard panels about 3-5 mm thickForm the main structure and reinforced layers1 roll × masking or paper tapeJoin folds and create replaceable wear surfaces1 bottle × washable school glue or low-temperature hot glueBond laminated parts1 × 10 × 10 cm thin-cardboard button capProvide the press surface4 × 2 × 8 cm folded-cardboard spring stripsReturn the cap2 × 5 × 5 cm aluminum-foil padsCreate switch contacts2 × paper clips or alligator leadsConnect the contact to a tester1 × low-voltage continuity tester or microcontroller inputDisplay the switch state

Tools

Ruler
Pencil
Scissors
Low-temperature glue gun or tape
Adult-operated craft knife for the top opening

Low-cost swaps

Use clean shipping-box cardboard instead of buying sheets.
Replace hot glue with strong tape and folded tabs.
Use copper tape or flattened paper clips instead of foil contacts.

Project-specific safety

An adult should handle craft knives and make difficult starter cuts.
Let hot glue cool before pressing a joint or testing moving parts.
Connect only to a battery-powered continuity tester or logic input; never connect the cardboard switch to mains electricity.

Orient the build

Place the build so downward hand press on the cap is on your left and momentary low-voltage electrical contact is on your right. Call the side facing you the front, the far side the back, the tabletop the bottom, and the opposite face the top.

Build it

Step-by-step instructions

Step 1
Cut the button box
Make a 12 × 12 cm base and four 4 cm-high walls with fold tabs.
Keep corrugation vertical in the walls for stiffness.
Step 2
Create the top guide
Cut a centered 9 cm square opening in a reinforced lid.
Leave at least 15 mm of material around every edge.
Step 3
Build the moving cap
Laminate two 10 cm squares and add four short guide tabs below.
Sand or trim tabs until the cap moves freely through the opening.
Builder checkpoint: After build the moving cap, the first subassembly should stay aligned when handled gently.
Step 4
Fold the return springs
Accordion-fold four 2 × 8 cm strips into equal V shapes.
Place one near each cap corner without blocking the center.
Watch for: If this stage binds or drifts, inspect contact bounce before adding more parts.
Step 5
Install the lower contact
Glue one foil pad flat to the base and connect its lead away from moving parts.
Smooth wrinkles that could cause early contact.
Step 6
Install the moving contact
Attach the second foil pad to the cap underside directly above the first.
Leave enough lead slack for full travel.
Builder checkpoint: After install the moving contact, operate the build slowly and confirm that momentary low-voltage electrical contact begins without binding.
Step 7
Close and test travel
Tape the lid to the walls with a removable hinge.
Press all four cap corners and correct any rubbing.
Step 8
Run ten switch trials
Connect the low-voltage tester and press in the center ten times.
Record clean signals, missed presses, and stuck returns.
Builder checkpoint: At the final checkpoint, The button presses at least 8 mm, returns after release, and closes the low-voltage contact on nine of ten deliberate presses without staying stuck.

See the engineering

Why it works

Input: downward hand press on the cap
Output: momentary low-voltage electrical contact
Motion: linear press-to-binary switch state
Energy losses: guide rubbing, spring fatigue, foil wrinkles, contact bounce

The linear press-to-binary switch state motion path, with the main efficiency losses called out.

Why this works

Normally open switch

Two conductive surfaces remain separated until the moving cap travels far enough to touch them. Folded cardboard springs store elastic energy and lift the cap when pressure is removed.

Look for: Connect a continuity tester and listen for one clear signal near the bottom of each press.

Where the energy goes

Efficiency and losses

The ideal model leaves out guide rubbing, spring fatigue, foil wrinkles, contact bounce. These effects turn some input energy into heat, sound, vibration, or unwanted motion, so measured performance will be lower than an ideal calculation.

Look for: Run the build slowly and locate the first place where guide rubbing becomes visible or audible.

Math bite

Find switch reliability

Formula: reliability = successful presses / total presses × 100%

Successful presses = 9
Total presses = 10

Substitute: reliability = 9/10 × 100% = 90%

Result: The prototype worked on 90 percent of test presses.

Guide and contact changes should raise repeatability.

A ten-press sample is small and does not predict long-term wear.

Brick-building meme reading: Chuck Norris does not build LEGO; he roundhouses the bricks into sculptures. — The button was pressed. The foil requested a cleaner meeting surface.Image supplied by the site owner.

Make it behave

Test, troubleshoot, and tune

Controlled test

Start here: Press once at the cap center with the circuit disconnected to confirm free return.

Success looks like: The cap returns above the contact gap and produces a clean signal on at least nine of ten presses.

Measure: Press travel, successful contacts, and return time.

Change: the folded-spring height

Keep constant: cap, guide opening, contacts, press location, tester, and trial count

low springs
medium springs
taller springs

Troubleshooting guide
Symptom	Likely cause	Confirm it	Fix
The cap stays down	Guide tabs rub or springs collapse	Press each corner with lid open	Trim tabs and replace springs
The tester is always on	Foil pads touch at rest or leads short	Remove cap and test each lead	Increase contact gap and insulate crossings
Presses are missed	Pads are misaligned or cap tilts	Press slowly and watch contact overlap	Enlarge pads or add guides
The signal flickers	Foil is wrinkled or cap bounces	Hold the cap down steadily	Smooth pads and add a soft contact spacer

Choose your tradeoff

Increase guide clearance before increasing spring force. Strong springs improve return but require a harder press; larger contacts improve reliability but can close too early.

Keep experimenting

Try another version

Easier

Mechanical clicker

Use the cap to tap a paper flap without any circuit.

Performance

Two-contact button

Wire two parallel contact spots for better reliability.

Creative

Game controller

Connect the button to a verified low-voltage keyboard interface with adult guidance.

Build together

Classroom and access options

Classroom version

Teams can compare the folded-spring height while keeping cap, guide opening, contacts, press location, tester, and trial count. Assign builder, tester, recorder, and explainer roles; have each team predict the result before collecting three trials.

Access adaptations

Pre-cut repeated pieces and mark fold lines with high-contrast ink.
Use large tabs, binder clips, and tape for easier one-handed assembly.
Make the cap 15 cm square and add a raised tactile symbol for a larger target.

Reflect on the design

How did the folded-spring height change the measured result?
Where did guide rubbing affect the build most strongly?
What evidence shows that normally open switch explains the motion?
Which change would improve momentary low-voltage electrical contact without creating a new problem?

Glossary

Normally open switch: Two conductive surfaces remain separated until the moving cap travels far enough to touch them.
Input: The action or energy supplied to a system; here it is downward hand press on the cap.
Output: The useful response produced by a system; here it is momentary low-voltage electrical contact.
Efficiency: The fraction of input energy that becomes useful output instead of friction, sound, heat, or unwanted motion.

Build your dreams

One build can start the next.

Share what you learned, change one variable, and help another builder understand what worked.

Explore more guides

Sources and build notes

An original BrickLabClips cardboard machine with dimensionally specified construction.

Cardboard design verification: Dimensions, fold allowances, repeated-motion joints, and likely load paths received an editorial geometry review.

Written and edited by BrickLabClips. Published 2026-07-22; updated 2026-07-22.

What you will build

Learning goals

Materials, tools, and safety

Tools

Low-cost swaps

Project-specific safety

Orient the build

Step-by-step instructions

Cut the button box

Create the top guide

Build the moving cap

Fold the return springs

Install the lower contact

Install the moving contact

Close and test travel

Run ten switch trials