Intro: The Great LED Light Bulb Pumpkin
Don't let the silly face fool you, this happy fellow is one of the smartest pumpkins in the patch. The giant paper mache pumpkin is illuminated inside with the new Flux Smart LED Light Bulb. Flux is a 40-watt equivalent, Bluetooth-enabled, color-changing A19 (standard) light bulb that is controlled via your iPhone or iPad (or Android device). In this application, we end up with a lively animated pumpkin that can dance with music and put on a dazzling light show for your whole neighborhood. Kids will love playing with the voice-activated response feature. The pumpkin is a pleasure to have around, light-weight and easy to move.
Supplies for the Pumpkin:
- FLUX Smart LED Light Bulb
- Large Beach Ball
- Paper Mache Mix (flour, water, salt)
- Paints (Apple Barrel Pumpkin Orange, Brown Oxide)
- Square-shape Cardboard Box (base)
- Duck Tape (Orange, White, Gray)
- Desk lamp for standard 60-Watt Bulb
- X-Acto Knife
Supplies for the Stem/Hat Topper:
- Deer Park 1-gal Water Bottle (cylinder shape)
- Paper Mache (use tracing paper for transparency)
- Paint (Kiwi Green)
Supplies for the LED Light inside the Stem:
- Pool foam noodles
- Adafruit.com Medium Size LED Backlight (4)
- 47 Ohm resistors (4) and wiring
- Rechargeable Lithium Battery (3.7 volt)
Step 1: Select a Large 42-inch Beach Ball
This project started out with the purchase of a Prextex Giant 42'' Inflatable Beach Ball with Mesh Beach Bag ( 2 Pack) from Amazon.com. The actual true diameter of the beach ball after inflation is about 27-inches, which is effectively the largest practical size for moving the darn thing around in the house. It takes a long time to inflate, and it takes a lot of paper mache to cover. Also winter storage might be a design consideration. Suffice it to say a 27-inch object will not fit into our attic.
Step 2: Apply Paper Mache to the Beach Ball
The idea is to inflate the plastic beach ball, and cover almost the entire surface with paper mache, leaving one approximate 12-inch diameter hole in the bottom (where the inflation valve is). The 12-inch diameter hole serves as the escape hatch for removing the deflated plastic beach ball after the paper mache has dried, and for the final project, the hole serves as the illumination port that the LED light bulb will shine up into.
The paper mache recipe used was 2 parts water per 1 part flour with a pinch of salt.
We used approximately 6 layers of newsprint style paper, being careful to use unprinted paper for the the first several layers. This way the inside of the pumpkin is uniformly cream-colored. We also used unprinted paper for the outer layer, to minimize the need for multiple layers of paint.
When you are satisfied with your paper mache work, let it dry thoroughly until hard. Then open the valve on the beach ball, and use some weights to slowly force the air out. If necessary insert a toothpick into the valve to hold it open. I was wondering if the plastic ball would adhere to the dried paper mache, but it did not stick.
- A paper mache project of this magntide is an incredibly messy activity. You will find that the dried paper mache mix is nearly impossible to remove from shoes, clothing and furniture (eg; kitchen table). We quickly decided to move the activity outside to the lawn.
- Be aware that ambient temperature changes will expand or contract the ball. Therefore, the ball may expand and burst through the paper mache. In our case, we conducted the project over 3-4 days and had to monitor the pressure of the ball periodically and add/subtract air as necessary
- The paper mache has to be thick enough to provide structural rigidity as well as opaqueness to block all light. Duck tape (white) can be used inside the pumpkin to cover over areas that may be transmitting unwanted light.
- A square or circular box or plastic bin is good for holding the ball in place as you apply the paper mache
Step 3: Paint the Outside of the Pumpkin Orange
Spray-painting the outside of the pumpkin is the next step, because the goal is to keep the inside of the pumpkin off-white, without accidentally getting orange paint in there.
I used Apple Barrel 20470E Pumpkin Orange Matte Acrylic Paint from Walmart's arts and crafts department. I used distilled water to thin it out (approx. 50/50) and I used a Wagner power sprayer (outside in the yard). One 8-oz bottle of paint was enough (save some for touch-ups).
For the dark lines on the pumpkin, I mixed Apple Barrel Brown Oxide and Pumpkin Orange. But the hand-painted details can be done at any time.
After the paint dried, I used some orange and white Duck Tape around the bottom hole which needed some reinforcing to prevent ripping. White Duck Tape is better for inside-the-pumpkin touch-ups, while orange is good for outside.
I did not paint the inside of the pumpkin as it looked great as is.
Step 4: Carve Your Pumpkin's Face
Now use an X-Acto knife to carefully carve your pumpkin's face. I made paper cut-outs of the eyes, nose, and mouth and traced those onto the pumpkin with a pencil. Be patient as it takes some time to cut through the thick paper mache.
Step 5: Create a Pumpkin Base With Desk Lamp
We simply used a square cardboard box for the base (approximately 19-in x 19-in x 16-in height). A suitable desk lamp for holding a standard 60-watt bulb is placed in the bottom of the box, with the light pointed upwards into the hole at the bottom of the pumpkin.
The box is easily decorated by draping a car blanket over the sides, and you could possibly use Easter grass around the bottom to capture some the light and simulate the appearance of hay in the pumpkin patch.
Step 6: Turn on the Flux Smart LED Bulb
Put the Flux LED bulb into the light fixture to test your creation. Out of the box, without any programming, the Flux bulb looks like an ordinary 40-watt light bulb with a nice warm color.
Now for some real fun, follow the Flux LED instructions to download the appropriate Flux apps for your smart phone or iPad device. The Flux bulb comes in both WiFi and Bluetooth options. Both are functionally equivalent but the WiFi has greater distance range and other secondary benefits.
Now you have a huge animated pumpkin with an attitude. This pumpkin is a blast to have running in your family room during the day. At night you can easily move him to your living room or upstairs bedroom to shine out the windows.
Now your neighbors will finally know what you've been up to!
Step 7: Green Stem/Hat Topper
To give the pumpkin some additional personality, the stem on the top provides a great artistic opportunity. I wanted to illuminate the Green stem with LED's if possible. However, you could optionally design the green stem without the electronics.
I used a crystal clear Deer Park 1-gal water bottle covered with several layers of paper mache made out of translucent tracing paper. Be sure to use an X-Acto knife to take the top and bottom off of the water bottle to create a cylinder (cover one end with paper mache, leave one end open for insertion of the light). When dry, the stem was painted green with slightly watered-down Apple Barrel Kiwi green matte paint.
The LED light design for inside the stem is a relatively simple LED light bar made out of four Medium size LED backlights available from Adafruit.com. See wiring diagram provided. The mounting I chose (somewhat unusual) was a 7.5-in section of 2.5-in dia. yellow foam pool noodle, covered with "donuts" of 3.25-in dia. green pool noodle. The green pool noodles donuts needed to have their center holes widened (X-Acto knife) to fit over the LED light bar.
The finished LED light assembly is powered with a 3.7 volt Lithium battery taped on to the rear. The Li battery can be recharged as needed.This assembly sits nicely on the top of the pumpkin, and then you place the stem/hat over the light.
The final appearance nicely shows off the green paper mache stem and is consistent with the overall spirit of the project. It may be possible to simplify the LED bar design (using normal printed circuit board instead the pool noodles). Suffice it to say the current design was arrived at by trial-and-error.
Step 8: Final Comments
The current design is intended for indoor use, or outdoors in good weather only (bring in at night). The pumpkin is light weight and easy to move around (assuming you can get through the door with it). The Flux LED Bulb is not approved for outside use at the current time.