In this instructable we will be building a homemade LED grow light. This light can be used for full time growing indoors or just for starting seeds in the springtime. This design can be adjusted to use many different color LED's and any light intensity that fits your budget!
What you will need - (Product links at bottom)
1. Several strips of 3/4" plywood or other similar boards
2. 1 piece of 1/4" melamine board (they can cut it to length at Home Depot for you)
3. One 2X4
4. Computer Power supply or LED Strip power supply
5. LED strip lighting (your choice) - Grow light strip + Connectors or 6500K Light strip + Connectors
6. Solder, soldering iron, and wire or strip light connectors
7. Eye hooks and rope/chain for hanging light
8. Wood screws
Note: Why melamine? This product has a shiny reflective surface that is resistant to moisture, is cheap, and flexible.
LED Power supply - http://amzn.to/2icTngm
Solder - http://amzn.to/2vN4Wh7
Soldering Iron - http://amzn.to/2vHU71v
Eye hooks - http://amzn.to/2vNyKKR
Gorilla Glue - http://amzn.to/2vNsQco
Step 1: Step 1: Making the Light Housing
You can watch the full video for a detailed visual of how this goes together or follow along with the below steps
1. Make your cuts
- Rip your 2X4 into 1.5" square stock
- Cut 2 pieces of the square stock to the desired length of your light (mine was 32")
- Cut two pieces of plywood about 3" wide by 22" long
- Cut your melamine into a 32" X 23" square
2. Making the slot
- Using a table saw or a circular saw, set the blade to about 20 degree angle and make a slot down the center of each piece of your square stock sides.
- Slide your melamine piece into the slot on each of the square stock sides.
- Using some force, bow the melamine into a parabola while screwing on each end piece using 2 wood screws
Step 2: Step 2: Attaching the LED Strips
In this step we will attach the strip lighting and make the connections. The LED strips do come with self-adhesive but I would also use some Gorilla Glue to ensure they do not come loose.
1. Gluing and sticking the strip lights
- Cut your light strip into as many 30" sections as you can, you can use more than one strip here to maximize light output
- Attach the LED strips using the self adhesive and Gorilla Glue while spacing them equally across the surface of the melamine (leave enough room at each end for connections
2. Making connections
- If you purchased the LED connectors for your LED strip (from the listed materials) then you can use those clip on connectors to connect the strips together. Start from one outside edge and connect the strips in a snake until you reach the middle strip. Then repeat from the other side so that you end up with the start of each "snake" in the center of the light at the same end.
- If you are using solder and wire (I used thermostat wire 18-2) you will need to follow the same procedure as above. To make solder connections remove the plastic waterproof coating with a razor knife and solder a positive and negative for each connection.
- You should be left with two positive and two negative connections hanging out from the center of the light. These will be connected to our power supply.
Step 3: Step 3: Using a Computer Power Supply to Power Your New Light
In this step we will be converting an old computer power supply to be used to power the LED light. Any old desktop computer power supply will work as long as it is above about 200watts
1. Preparing the power supply
- Clip off all of the Molex connectors from the ends of the wires
- Locate the green wire and twist it together with any one of the black wires, tape or wire nut this connection
- You can also place a small hobby 12v switch on that connection
- All of the yellow wires are 12v and the black wires are ground. The rest of the wires will not be used.
2. Connecting to the light
- if you are just powering one light you can twist together all of the yellow wires into one wire nut and all of the remaining black wires into another
- Run a lead wire from each connection (yellow is positive and black is negative) to the positive and negative connections on the LED strip light.
- You can use a dab of hot glue or white duct tape to secure the wires to the light and hold them flat against the surface. You could also use a wire staple or other connector to secure the wire to the light frame so it does not pull on the LED strip lights as it is move around
- Plug in and turn on the power supply and test all your connections. All LED strips should be lit at this time.
Step 4: Step 4: Growing With Your New LED Light
I have used these lights in many different LED strip combinations to grow plants year round and also to start seedlings in the spring. Although these grow lights do not compare to more expensive off the shelf LED grow lights they are much cheaper to build and get the job done for the hobby grower.
LED vs CFL DIY light comparison video here -
Check out the SSLFamily at www.sslfamilyfarm.com