Instructables
Picture of LED light strip in wood housing
I have a desk with a shelf above it, so I made a light strip I could put on the bottom of the shelf to light my desk area.  I had some LEDs sitting around, but no simple way to make a circuit board for them, so I make a wooden housing to hold the LEDs and make a simple lighting strip.  I made it at techshop in menlo park (http://www.techshop.ws), using some tools in the woodshop and basic tools like the soldering iron.

Materials:
Pine board (section of a 1x12, about 19 inches long)
25 white 5mm LEDs
1kOhm resistor
power cord

Tools:
Table Saw
Drill Press
soldering iron (and solder)
clamps and glue
multimeter (optional)

Precautions:
Power Tools
Mains voltage
 
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Step 1: Wooden housing - blade depth

Picture of Wooden housing - blade depth
For the wooden housing, I basically created a U-channel by cutting a large groove near one edge of my board, then cutting the whole thing off from the board. 
To do this, I first removed the blade guard assembly and lowered the blade so it wouldn't cut all the way through the wood.  (My groove was shallow enough that the LEDs are completely contained- if you want them to stick through the holes, you can make a deeper groove with less material remaining.)

Step 2: Wooden Housing - cutting grove

Picture of Wooden Housing - cutting grove
Once I'd set the blade depth, I set the rip fence so that the edge of the board was about 3mm past the edge of the blade, and cut a groove.  I then moved the fence over a bit and cut another groove, repeating until the groove seemed big enough to house the LEDs (about 3/8 of an inch).  Then I moved it a bit further over and brought the blade up high enough to cut all the way through the board, and cut it off.

I also cut one a very thin strip of wood that I'll use later to cover the back of the assembly.
nevadavic1 year ago
kool project. I think for mine, I will plan to put all the LEDs in parallel, that way one dead LED will not knock out the whole string. requires more math but you have a solid project!
and use a 120vac-12vdc xfmr from a thrift store to prevent flicker and help w/ safety.

Putting the LEDs all in parallel is a good choice. A 100 ohm resistor every 3 or 4 LEDs will stabilize the current. A 12v wall adapter is the best option here. Using mains voltages is quite dangerous.

theunsame1 month ago

Cool project. I'm very interested in blending wood with LED technology. Is there any issue with heat in this application? Others use various heat shields etc.. Thanks!

hickhamt1 year ago
any action shots available?
nodoubtman1 year ago
don't forget a diode, by exemple : 1n4007

thanks!
marC:)
Cartago2 years ago
Good instructable, but you shouldn't have soldered them in serie, because if some LED breaks down, all of them are going to turn off. So, you should solder them in pararel.
acosand (author)  Cartago2 years ago
That's a good point, but I wanted to keep the wiring fairly simple here. To run the LEDs in parallel I'd need a power supply that would source half an amp at a little over 3 volts, and a way to make sure each LED had about the same amount of current flowing through it. You could use a high-power USB charger or something like that for the power source. Depending on the variance in the LEDs you might need a small resistor for each one to make sure you get current through all of them.
Cheers.
You should group the LEDs in blocks, like each 4 LEDs in series, and then connect these blocks in parallel, it would make repair easier, because if they are all in series if one breaks down it will be hard to find, especially if you have a 100 or more of them.
Cartago acosand2 years ago
You're right.
pandyaketan2 years ago
Nice work... hope it survives the Mains voltage fluctuations, since a resistor has been used instead of a capacitor, which can absorb the shocks better...

I have made some LED projects using caps, sensors, etc... incase people are planning to make some...

BE EXTRA careful, since you are dealing with AC Mains (both 110V or 220V).

reg
ketan


justbennett2 years ago
I think I saw somewhere where somebody used LEDs on AC by wiring some in both directions. I think it would simply mean you make two circuits similar to this one, but one going the opposite direction. I don't know if that would change the characteristics of the light, but I think it leads to more efficient use of the current.


Nice simple project though! Please update us if anything blows up.
acosand (author)  justbennett2 years ago
You should be able to make a rectifier using 4 LEDs (or normal diodes) and then connect the rest of the LEDs to the rectified voltage. You could also use a center tap transformer and two diodes, or just get a DC supply. I wanted to keep this one simple, but I may do some fancier wiring in version 2.
Thanks.