Grow Lights Made From LED's and Cardboard




Introduction: Grow Lights Made From LED's and Cardboard

About: i like robotics, tinkering with electronics and plants/ Herbalist.

this instructable should show how i made a (mostly) full spectrum LED light grow light on an old pizza box disk.

Step 1: Materials

you will need some materials:

Led's-at least 6 (i used 14 Led's of 6 different colors, the more variety of colors the better)

Wire- 22 gauge 2 wire cord ( i had 10 feet and had a good deal of extra left over, used less then 3 feet)

USB 2.0 cable- should have 4 wires (generally red is 5+ green is data +, white is data - ,and black is 5v-)

Solder- i only used 1 foot of solder but i wasted a lot

Switch-to turn on and off (i used DPST)

tin or aluminum foil- to cover the top for a nice sleek look

Card board- size doesn't matter ( i used a 12" pizza disk that comes in frozen pizza boxes, to could go way smaller and have a more traditional compact design but i didn't)


Rope- to hang the light maybe

temp sensor- just cause you have 2 extra data wires you can mess with if you want to.

Step 2: Tools

you will also need tools:

Tape- for holding stuff together or use a hot glue gun

Safety glasses- to protect your eyes

Needle nose pliers- to twist wires together before soldering

Diagonal cutters- to cut wires and solder

Solder gun- to heat the solder and kind of glue stuff together with the solder

Small hole punch- to punch holes in cardboard for LED's to sit in

Step 3: Punching the Holes

Use the small handheld hole punch to make holes in the cardboard. this makes the holes for your LED's to sit in. I used a sharp pencil to make holes near middle of cardboard because the hole punch couldn't reach in that far but it wasn't as good as a hole as the hole punch made. maybe punch an additional hole(s) to wrap rope or cord through to hang the light.

Step 4: Check the Proximity of the Cuts

place the LED's into the hole to check the size of the holes, then keep them stuck in using tape or glue. the holes from the hole punch should be somewhat evenly spaced out, doesn't have to be perfect. the LED's colors should be mixed to get her so one side isn't more of a single color then the other.

Step 5: The Power Cord

solder wires to the switch and one to the USB cord. remember the USB cords usually have 4 wires generally red is 5+ green is data +, white is data - ,and black is 5v-. you should have one wire going to cardboard holding LED's and the other end going towards the USB cord. the extra data wires can either be taped down or and additional accessory could be added for data logging, like a temp sensor.

Step 6: Solder the Wires and LED's

Solder all the + positive lead on the LED's together, they are the shorter ones. then solder all the negative leads on the LED's together, the longer leads. don't forget to test all LED's and some LED's might be to small for the 5 Volts of the USB so you might have to add resistors, i didn't because the LED's i used where big enough to handle the voltage and amperage from my laptop, and to be that much simpler. this should have all wires connected now. i used mainly 3 colors of LED's , blue, red and Green. I also had 2 yellows and 1 white LED.

Step 7: Optimal Step: Add a Cover

Use the tin foil to cover the top of the cardboard and having no contact with any wires or solder. i wrapped all wires with tape to stop from unnecessary contact between wires and foil. the power cord can stick out of the top or side, doesn't really matter. wrap around the cord you maybe using to hang the light.

Step 8: Congratulations

you should have a fully functional light, which is basically a bunch of LED's to be used to grow plants or anything that requires light. the light that comes off is dependent of what color Led's you use. I compared it to a regular light bulb, they give off about the same amount of luminosity ,but the color is defiantly different. the light can be hanging or mounted to a wall or stand.

Make it Glow!

Participated in the
Make it Glow!

MAKE ENERGY: A US-Mexico Innovation Challenge

Participated in the
MAKE ENERGY: A US-Mexico Innovation Challenge

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    7 years ago on Introduction

    The idea is nice and I like the low-tech / cheap materials approach. But to have any effect on plant growth, I believe you need a lot more leds and place them closer to each other. It may also be a good idea to use the aluminium foil as a reflector on the cardboard, to utilize as much as possible. It could simply be laminated onto the cardboard piece with paper glue.

    Commercial LED grow lights come in all sorts of size and luminosity, but they alle have in common that the leds are very tightly placed in order to give max intensity per area. I have experimented with grow lights for quite a while and I still frequently underestimate the amount of light plants actually need for growing well.