This project is rather flexible, look out for 'HAVE TIME?' parts the may allow you to improve the project and feel better about being more accurate.
Note: This illuminates when the light is ON, not on when the light is off, I personally don't like too many lights on when I sleep so this automatically dims when the light is off.
You also do not have to create the dimmer circuit, you can have it permanently on, or on when you turn the light off, its up to you. its a great flexible project. Assembly time is about 5-6 hours.
What you'll need:
- A set of mirrors, I recommend the ikea 'LOTS' http://www.ikea.com/gb/en/catalog/products/39151700
You get 4 very light mirrors, adhesive pads and these are only a 5 pound.
- about 8 feet of square dowel (about 10 x 10mm)
- Your favourite adhesive, I prefer 'no nails', or wickes own: forget nails
- something to put the mirrors on the wall, ideally the adhesive pads you get with ikeas 'LOTS' Mirrors
- LEDs, any colour ideally half the width of the wood, for 10mm wood, 5mm LEDS. I've used 20 Blue. You can use more or Less LEDs dependent on how you want to position them.
- Wire, something thin, that can handle at least 20 volts to be safe, speaker wires usually flexible and safe enough.
- A power adaptor, I have a 4.5v 400mA at hand so I used that.
For the Auto dimmer switch
- Veraboard (PCB)
- A transistor
- LDR (Light Dependent Resistor)
If you would like your light to be slightly dim when the room is pitch black you'll need a resistor. Mine was trial and error to find a decent one that would work. Also i do not know much about components so it was just playing about with things till i got it right.
Step 1: Cut the Wood
My project is based on 4 mirrors, the top mirror will have two side pieces and a top piece. the next two down will have only side pieces of wood side you will not see the LEDs shining upwards to the next mirror so that is not necessary. and the base piece will need two at the side and one at the base.
Ideally use a right angle to mark where to cut, I just used a junior hacksaw to cut it.
HAVE TIME? Cut 45 degree angles so the fit neatly.
Step 2: Drill the Holes, and Mount the LEDs.
Tip: Do not glue the LEDs until you know they're all straight, if not your light beams will look wonkey!
Now drill the holes in your wood, and make sure they are adequate. if you are unsure, start small and work your way up. once your ready start drilling your wood. dont forget something to lean on so you dont go into your table. I used my drill box.
use a clamp to prevent the wood from splitting, and also to stop it spinning.
Once you have done this place, you LEDs into the wood and plan where you want to place them.
Do Not Glue Them Yet!
I forgot to include an image but you need a hole for your power cord/Socket to go in, so make sure you include one center hole in one your piece of wood, you also need another hole next to it, for the wire of the LDR to go through too. for asthetic reasons, I keep the center hole for the power and offset the LDR hole since this doesn't need to be on the center.
Step 3: TIP: How to Solder Loads of LEDS Without Cutting the Wire
Nip with wire cutters, each end of the wire plastic but don't cut the wire inside.
Using your nails, (if you have any) force the wire apart, by pushing the wire in opposite directions, this should split the wire apart.
Nip the inside of the wire with the wire cutters.
Without cutting the wire. pull the wire up away from the two nicks you have made exposing the wire.
It may be hard for some people. I don't know, its my best, and quickest way to solder lots of LEDS in parallel form.
Solder the LEDs
Remember: LEDs will only work one way, so make sure the polarity is correct. test each led before you solder it.
Step 4: Soldering the LEDS and Gluing the Wood.
This part can be a bit lengthy, but once you get going with some good songs, you'll be ready to go, and done in no time. Don't forget to test that the LED works and is the correct polarity.
If your wire has one colour marked on has a strip to indicate create a rule that you can remember. LEDs have one leg longer than the other so you know that is the anode and the cathode.
"striped wire goes to longer leg" - something like that.
Although you can't see it, the wire I used had writing on one side.
When gluing dont smother it in glue or it will slide when you are tring to put pressure on it. I used the other mirrors to apply pressure, while i was soldering the other Mirrors.
Leave a wire to go from the current mirror to the previous mirror.
Step 5: Adding Plugs and Sockets
Ive super glued the plug to the miror so it stay in place.
Step 6: Testing!
How do i know if an LEDs go too much power going through it?
If it quickly goes bright then dims, then youve most likely damaged it.
If it goes bright then it extingueshes, then youve just blown it, it most likely get, hot, turn black inside and sometimes pop so be careful!
If it stays bright, your ok, but if it is getting warm, you are overloading the poor thing. LEDs generate, very little or no heat.
its down to good judgement, but bear in mind, that if you are going to make the dimmer curcuit, it takes the brightness about 20-30% so bear that in mind.
Below is how it should look. Notice how the plug goes from one mirror to the next.
Ok, now that you soldered and glued
Step 7: Power and Circuitry
Now, if your happy, add a switch if you like, add your power supply, and your ready to go! Use some sticky pads or some screws to hang your mirrors up and your ready!
If you want to build a simple curcuit then read on.
You'll need a transistor, various Resistors, and LDR and ideally some PCB to put it on. I played about a lot with this curcuit so its all down to testing and trail and error. Some things to bear in mind. I tested mine on some breadboard so i had an idea what i wanted to solder.
- Make sure that in the even in the room getting brighter (sunlight, bright lights) i dont know, the power is not going to blow your LEDs
- If your doing this at night (like i was) make your room as dark as you can to ensure that the lights are either off, or dim enough if you are going to use the resistor to keep the light on very dim when there is no light at all.
this is a really great site to learn how transistors work, and taught me how how to build this neat circuit!
Step 8: Final Parts
Now weve done most most of the work, the only thing that is left is to do is to place it on the wall. I have used the adheseive pads that came with the ikea 'LOTS' mirror set, they seem to be fine, but i cut them to size so they fit on the wood more appropiately.
Obviously test the mirrors before you mount them, and your done!