Introduction: LED Keyboard Costume/Prop

About: I have fun woodworking and DIYing stuff while spending way more money than the mass produced item would cost.

This was requested by my kid who wanted to be her beloved gaming keyboard (with the changing LED lights) for Halloween. I only had a few days to make this and utilized the help of a Cricut to cut out all the individual keys and their respective key letters. Kid also wanted the keys to be pushable. This project requires quite a lot of cardboard so save up if you want to make this. The keys were made from thin file folder cardboard (about 28 pieces of 8.5" x 12") and the case was made from an old shipping box saved for this project. The final width of the keyboard is 24", but you can adjust the pdf to your purposes. It's not a 101 key keyboard (you can update the pdf template), I didn't have enough time so I truncated it to what I could do in the 2.5 days.


Cost estimate (~$40) depending on what materials you have on hand:

  • Battery powered LED lights
  • thin file folder like cardboard (or 100 lb cardstock)
  • large corrugated shipping box (about 30" x 28") - glue smaller pieces together if you can't find a large cardboard piece
  • velcro
  • black acrylic paint
  • white marker
  • back brace support (if you want to wear it)
  • clear 5 mm plastic laminate sheets (empty sheets run through laminator)
  • 11 mm diameter springs (1 for each square key, 2 more longer keys)
  • glue for cardboard (I used super glue for fast drying time)
  • hot glue gun/glue sticks
  • USB cable (optional, just for additional coolness factor)
  • duct tape/packing tape

Step 1: Construct Keyboard Shell

I chose to make my keyboard 24"x11"x3". Simple PDF template is included in this Instructables. You can use a template maker to get the cut out of the box. I made sure there were flaps that covered the two sides and bottom. I eyeballed and drew the outlines directly onto my cardboard. If you don't have a large cardboard panel, you will have to cut and glue pieces together to form your keyboard. The depth of my keyboard was 3" before I bought the springs. When adding the keys with the springs, I found the keys to be too recessed in. I made a platform/torsion box of 5/8" to raise the back platform up. Another piece of cardboard was glued on top of the torsion box. You can make the depth of your keyboard 2 3/8" instead to save this step.

Don't cut the opening for the keys until you have all the keys done. Once all the keys are done, you can lay out the keys and measure the correct opening. In the picture, the opening is already cut out and is flipped "opened".

Step 2: Cut and Glue Keys From Cardboard

The SVG files included here can be used with a cutting machine, or print out and hand cut (good luck if you hand cut). I used a Cricut with these files. The score lines (all inside lines) need to be manually changed using the Cricut Design Space software. The key letters were added in after the template was loaded into the cricut design space. You can save this step by writing the letters after the keys are painted (like the non-square keys). I wanted the lights to shine through the letters. After cutting them, glue the tabs using super glue or whatever glue of your choice. I needed to be done with this fast, so I used super glue. After they are all glued, paint with acrylic craft paint.

I didn't have enough cardboard to fit glue tabs for the sides so I just used packing tape to tape the 4 sides together after the paint dried.

If you decide to cut the letters out, the keys will need some support so when a person pushes the keys, the box won't collapse. Use the plastic laminated sheets (needs to be fed through the heated laminator) and cut out a little smaller than the size of the top of your key. For the square keys, cut out 1.5"x1.5" pieces. Glue these to the underside/inside of the key using a few dabs of hot glue. Make sure you don't dab the glue onto the letter/number openings. To handle the letters/numbers like A, P, 8, etc with the cut-out not attached, easiest way is to color in with a black sharpie on both sides of the glued plastic laminated sheet. One side is okay, but coloring both sides will make it darker. Skip this step if you do not have the letters/symbols cut out of the top of your key.

At this point, you can also write in the key names for caps lock, enter, delete, shift, etc with a white marker.

Step 3: Cut and Tape Bottom Supports

The SVG template files are included for the bottom supports. If you use a cutting machine, make sure to update the score lines before cutting. Once these pieces are cut out, fold along the scored lines. The easiest way to attach this is with packing tape while holding the bottom support tight to the bottom of the cardboard key. Hot glue sticks out too far and ends up burning fingers. I pre-cut the packing tape (cut into thirds across width of tape), and used that to wrap around the bottom support, attaching it to the cardboard keys.

Step 4: Glue on Springs

For the smaller keys, one spring is enough but for the bigger keys like the space bar, you will want to add one spring about 1" from each end.

Add enough hot glue (slightly bigger than the diameter of the spring) to the middle of the plastic laminated sheet on the bottom of the key. Quickly add the spring and hold for a few seconds until it has time to set up and place upside down to cool down and dry. Check to make sure the springs are not crooked. This will affect how square/straight the key is when you glue it to the cardboard platform.

Step 5: Measure Keyboard Case Opening

Arrange your keys on a flat surface and allow for a little bit of wiggly room in between each key. You want the LED lights to come through and the keys to be able to move up and down without damaging the neighboring key. Measure the height and length, and add about 1/8" extra to both measurements.

On the front of the keyboard case, where your keys will be, find the center point but drawing an X from corners to corners. If you have a speed square, you can easily draw a square line from the center point for both length/width of the keyboard. Divide your measurements in half, and mark from the center lines out. Once you have your rectangle opening drawn out, check again to make sure your keys will fit in that space and that is centered on the cardboard. It's okay if the opening is too small, you can always enlarge it, but not the other way around. Cut out the opening once you have confirmed the keys will fit properly.

Test fit all your keys inside of the opening and enlarge the opening if necessary. Also, using a scrap paper/cardboard, place it along the short edge of the keyboard and mark where the spring locations are. This will help you position the LED lights in the next step.

Paint the keyboard case with acrylic craft paint (only the outside faces).

Step 6: Add LED Strip

The battery pack and remote will be attached to the back of the keyboard using adhesive velcro. Cut a rectangle that is the width of the led lights, near the top left corner (if you are looking directly at the opening) of the keyboard. String the led strip from the back of the keyboard through.

Using the "spring location" template from the last step, lay out and tape down the LED strips into about 3 rows (depends on what LED lights you bought) away from the spring locations. The LED strip needs to be in between the springs. I used scotch tape because I didn't want the lights to be permanently attached to this costume and in case I needed to adjust the position of the lights after the keys are glued down.

Step 7: Glue Down Keys

After gluing these keys in, my recommendation is to put all the keys into the keyboard case first with the cover down. This will help with alignment (you can see the first row is a wonky, with the backspace key the worst looking) and also ensure you will not be gluing down onto the LED strips. You may need to move the LED strips around to avoid this.

One key and row at a time, put hot glue on the bottoms of the springs and glue down onto keyboard case. Hold gently in place for about 20 seconds until the glue starts to set up. After you have completed one row, lift up the keyboard cover and remove the row of keys below. Use a small piece of duct tape (1/4" x 1" is good enough) and carefully slide it onto the bottom opening of the spring and tape down. This will help ensure your spring/keys won't pop off later. Repeat until you are done gluing and taping all the keys down.

Step 8: Finishing Touches

At this point, close the lid opening and turn on the light strip. You may need to move the strips a little bit up or down if you can see it through the keys.

Cut 1" velcro squares and attach to the side and front flaps of the keyboard lid. This will allow you to open the keyboard later on. Also add velcro to attach the battery pack and remote control on the back of the keyboard case.

If you want to add a way to wear the keyboard, measure the shoulder length of the person wearing the costume. I used a back brace I already had, but I didn't want to permanently attach it to the keyboard. After marking the length on the back of the keyboard case, I used duct tape to make a loop opening for feeding the back brace straps through. This needs to be reinforced with extra duct tape strips after.

Cut out a little hole for a usb cable to dangle out of if you want to make it look more realistic! I tucked the restf the cable inside of the keyboard.

Halloween Contest 2019

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Halloween Contest 2019