Easy DIY Heavy Duty Push-button With Upcycled Material

Are you looking for an easy way to build an easy push-button for school (or other) projects that can handle a punch or be (literally) stepped on? Then this instructable is for you.

All you need is 10-30 minutes (depending on size and decorative factors) of your time and (mostly) household materials or “trash”.

Also, you can take the push-button apart, if you don’t need it anymore (if you use tape and no glue).

This concept is based on the original “Kartoffelsackschalter” (potato-mesh-push-button) designed by Mirek Hancl (@infchem / www.hancl.de). You can find the original instructions here: http://www.codingmakingunterricht.de/kartoffelsackschalter.pdf (in German, but the pictures speak for themselves). I am using his work under the CC-BY-SA license (and with personal permission).

This is my first instructable and English is not my first language, so I am grateful for any suggestions. Also, feel free to ask any questions about the project or the steps, if anything remains unclear.

You should (mostly) be able to complete the instructable by just looking at the pictures. (And, I tend to write too much in too much detail – so now, you’re warned. ;-) )

Supplies

Materials

All the sizes are relative to each other, there is no set size.

For this easy-to-build (single) push-button you need:

• Two equal pieces of aluminum foil (It can be crumpled up, torn, used, just not greasy or otherwise dirty on the parts that should make electrical contact)
• One piece of plastic mesh, a little bigger than the pieces of foil (from packaging of potatoes (hence the name), onions, garlic, lemons, …) (The wider the mesh, the easier the two pieces of foil will make contact when pressed and vice versa.)
• Either one piece of cardboard, twice the size of the mesh, or two pieces with a little more than the same size as the mesh (the original design uses duct tape for the enclosure)
• Electrical cord (the one with the braided wire inside, not the single-wire-one)
• Something soft to bolster one of the pieces of foil (You can use anything from foam rubber (expensive, but really awesome triggering results) over scrap pieces of cloth (old socks work nicely) to the simple tissues that I am using in this example)
• Clear tape (You can also use copper tape, but I have not encountered any difference in connectivity between the cord and the pieces of aluminum foil)
• Optional: a connector box / screw terminal (as can be seen in the picture) is useful for testing and the final build, but you can also use alligator clips, solder the cord to a circuit board or just twist the wires together

Tools you need

• A pair of scissors (or something to cut the cardboard, the mesh and the foil with)
• Something to cut and strip the cord (I use special pliers for that, because I have them, but you can use anything that works)
• Something to test the push-buttons with (like a simple led-circuit (as shown) or a multi-meter)

Step 1: How Does the Button Work? (For School and / or Troubleshooting, Can Be Skipped Otherwise)

You can skip this part, if you want to start building immediately, but you might need it for troubleshooting, if the push-button has a hard time working / closing the circuit.

You have two pieces of aluminum foil and between them, you have the mesh. When you push on one or both sides of the construction, your finger pushes the foil into the holes of the mesh onto the other foil – and they make (electrical) contact. When you lift the pressure, the mesh separates the two pieces of foil again – killing the electrical connection.

In Mirek’s design, the finger touches the duct tape enclosure and presses trough it firmly, but soft enough to push the foil into the holes of the net to make contact. In my design, this is harder to do. The cardboard’s rigidity evenly distributes the pressure. Therefore you need the padding element to have something to softly push through the mesh or (from the other perspective) absorb the structure of the mesh, while filling up into the holes of the mesh, pushing the aluminum foil through it.

Therefore, if your button works too unreliable, it could mean that the padding is not thick enough. It could also mean that the cardboard is too rigid or the mesh to dense. Both of these last points can be tested by literally stepping on the cardboard and checking whether high pressure changes the reliability or not.

Step 2: Cut (and Fold) the Materials to Size

Use the smallest part you have as a measurement (cardboard / aluminum foil / plastic mesh / padding).

Cut the other pieces accordingly.

The pieces of aluminum should a bit smaller on all sides than the mesh – the mesh needs to cover all of the blank foil. Any excess foil can be covered by clear tape. The mesh should be a bit smaller than one side / half of the cardboard.

If you are using a double-sized piece of cardboard (as I do), fold it in half. Use a ruler as a guide and / or score the cardboard with the scissors or a knife beforehand (if it is multi-layered).

(To get the most out of your bought plastic mesh / net, never just rip it open - simply cut it open at the top.)

Step 3: Add the Padding

Now, add the padding and secure it as needed.

You can also do this step after step four, if you choose to glue the edges of the aluminum foil to the cardboard to form a pocket. Then you can use smaller bits and pieces of padding, but you can’t take the button completely apart as easily afterwards.

Step 4: Strip and Connect the Wires

Strip around one to two centimeters of the cords on one end (the one that will be attached to pieces of aluminum) and one centimeter on the other end (or as much as needed to connect it to whatever you like).

Fray the side slightly, forming a sort of flat triangle to get a better connectivity to the aluminum. I twirled the other side to make it fit nicely into the connector box.

Now, take a piece of clear tape and firmly attach the flat frayed part of a cord to a piece of foil.

Do the same with the other cord and the other piece of foil.

Always connect and run the cords on the backside of the aluminum foil, the one that does not make contact with the mesh and the other piece of foil – otherwise the tape will insulate the pieces of foil from each other and the cords might also get in the way.

Step 5: Build and Secure the Layers

Now it’s sandwich time. Start by covering the padding with aluminum foil. Make sure the unconnected side of the foil is facing away from the cardboard / padding.

(As stated in step two, you can also glue the edges of the foil to the cardboard to form a pocket. If you do this, first only glue down one corner and the connecting sides, so you have enough leeway to bolster the pocket up without ripping the foil. You can glue down the rest later, if needed.)

Then put the mesh and secure it to the fold of the cardboard. Make sure it covers the complete area where the two pieces of foil could touch. (You can have extensions of foil on opposite sides, if you need them, just insulate them if needed.)

Last, add the second piece of aluminum foil. The side with the cord attached should face the cardboard.

If you use two parts of cardboard, connect them with tape.

If not, fold the cardboard and…

Step 6: Test the Button (and Troubleshooting)

If you press the cardboard, the circuit should close. You can test this with a simple LED-circuit, like I do here, or with a multimeter.

Here, the connector box comes in handy, especially if you want to use the push-button with a microcontroller, like an Arduino.

You can also attach the connector box directly to the cardboard with hot glue or screws. For this, you need shorter cords and a longer side of cardboard on the underside of the push-button. Use a nail to easy make holes for the screws a short distance from the edge.

If the button doesn’t work properly, open it up again and press the second piece of foil down on the mesh, the other piece and the padding. If this works, enlarge the padding (if possible) and / or use more force after you have closed the push-button again (e.g. step on it).

If it doesn’t work: Test the connectivity between the cords and the pieces of foil.

Else: Test your test circuit, power supply… or seek help in the comments. (And read “How does the button work")

Once the push-button is tested and works reliable: Have fun! You now have your first own DIY heavy duty upcycled push-button.

Step 7: Optional: Make It Look Nice

If you are doing this with kids or pupils, don’t skip this step (like I did). You could just add colored paper or let the kids go wild with crayons and markers (on the outside, that is).

In any case it might be a good idea to mark / outline the overlapping area of the two pieces of aluminum foil on the outside – since this is the part that should be pressed.

Step 8: Two or More Buttons in One (also: AND-logic Gate)

You can easily split up on push-button into two (or more) connected ones. Just cut the aluminum foil that is not padded in half (third, …) – all the way trough. Separate the two pieces a short distance so that they don’t touch. You can also put a piece of clear tape over the rift and the edges of both new pieces, to keep them securely separated. Connect a new cord to the backside of the new piece.

Now, depending on your wiring of the push-button, you have to buttons with a common lead or even one “AND”-logic gate button, were both parts have to be pressed to close the circuit.

Step 9: More Complex - and Bigger

More complex buttons - [o] <- buttons inside other buttons:

You can also create more complex buttons by having a segment inside another segment or other ideas – just remember to always connect the cord to the backside of the aluminum foil and to run the cords on this side, between the cardboard and the foil, as well, to not hinder connections.

You can create a push-button-mat for dancing games or as a push-up-/plank-trainer… there are no limits.

Giant push-buttons:

Since aluminum foil comes in long rolls and big pieces of cardboard are also easy to come by, you might even want to make a huge push-button (segmented or not segmented). Luckily, the packaging mesh used can be easily sown (with a sewing machine or even by hand). You don’t need much skill for that and it works like a charm – as you can see on my upcycled marbles net. I will add pictures of huge buttons once I’m finished building them.

Step 10: Example: Doormat-alarm

Put one of the push-buttons under the doormat. The weight of the mat does not suffice to trigger it. It's hard to see, but a human very well does. ;-)

Step 11: Have Fun Making!

So, as you can see, these push-buttons are very versatile, easy to build and heavy duty. Have fun and I would love to see your results!

And again, a shoutout to Mirek Hancl (and his colleague) for getting me started with coding and making stuff from scrap and giving me the basic idea for this.