LED lighting system

Discussion in 'The Projects Forum' started by davidbenjamindix, Jan 1, 2011.

  1. davidbenjamindix

    Thread Starter New Member

    Feb 25, 2010
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    i wasn't sure which category to post this in, so i chose this one.

    I am a woodworker, and building a 20" x 20" x 20" walnut lockbox. I would like to have a LED light system in the interior, but I don't know where to go, or where to start. I'm looking for any suggestions, advice, hints, etc. There will be multiple shelves on the interior, and the bottom of the box will probably be flocked (flocking is a dust felt that is attached to a surface with an adhesive). i would very much like the lights to be somewhat bright, but not shining right in my face when the box opens, and the doors are on the front side (open towards you). i have a 12 volt battery recharger, so i assume i will be running 12 VDC. i also have a 4 channel 12 VDC remote control system (i am running some type of actuator or solenoid off of also), and have yet to determine if the LED's will run directly off of the recharger, or out of the remote system. i think i would like the LED's to turn on automatically when the front doors are opened.

    the problem i have is funding. i just started a small business (custom woodworking, piano tuning, live piano music, beekeeping, selling local honey, small-party catering, photography for any occasion), and it's a slow start. basically im shopping cheap. i don't know how many lights/strips i should use for a project this size.

    if you would like to see the project in the works, i have most of my woodworking photos posted on my facebook account. feel free to add me as a friend, and you can see what i'm working on. it make help whoever is interested understand what it is going to look like.

    my facebook name is David Dix, and my profile photo is a profile of me looking at a firebird. thanks for your time!.

    David
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    LEDs are very cheap, especially if you harvest them out of other devices. I assume for the sake of argument that you want white ones. Look for cheap broken flashlights.

    You can get by with just a few components. If you want to use batteries only you can, but you'll need a switch. It would be cheaper to use a wall wart.

    Some electronics theory is needed to use LEDs correctly, namely Ohm's Law. This is to calculate the resistor the LED should have matching it.

    If you give use the LED type and voltage of the power supply we can get you pretty close to the needed resistor.

    Chapter 1 and 2 cover most the ground you would need for a LED circuit.

    LEDs, 555s, Flashers, and Light Chasers
     
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  3. tracecom

    AAC Fanatic!

    Apr 16, 2010
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    You can buy LED's suitable for your project pretty cheap on eBay. Here's an example.

    http://cgi.ebay.com/100-pcs-5mm-Whi...314?pt=LH_DefaultDomain_0&hash=item255ff6984a

    As you will notice, the LED's ship from the Far East, so delivery will take a few days. The quality is spotty, but they will be plenty good for what you want. Also notice that the LED's come with free resistors, which is good. But you will need to decide about your power, etc. before you will know what value of resistors to order.

    I haven't seen your cabinet, but it wouldn't take very many to light it well. Post a photo here, and someone will offer suggestions. :)
     
  4. davidbenjamindix

    Thread Starter New Member

    Feb 25, 2010
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  5. wayneh

    Expert

    Sep 9, 2010
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    I was in the Menard's yesterday and found strips of LEDs on a flexible band, almost like tape, that are intended for exactly this kind of application. They weren't cheap, but there was a lot of the "tape" in each package. The LEDs are surface mount, the conductors are flat copper, and the flexible band is very flat. I think it really could be a handy technology to have in your "bag of tricks". You might want to become familiar with this product before trying to roll your own substitute.
     
  6. edgetrigger

    Member

    Dec 19, 2010
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    if the 12v battery charger that you mentioned is freezed, then the number of leds you can use is determined by the power handling capcity of that charger. Check its wattage of current rating.
     
  7. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    The on/off can be done by embedding a Normally Closed reed switch ($3) in the lid, and a magnet in the base. When the lid is opened, the switch will close, completing the circuit and lighting the LEDs.

    If you order the LEDs new so their forward voltage and current are all equal, you can use this: LED series parallel array wizard to calculate/draw your circuit wiring diagram.
     
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  8. CDRIVE

    Senior Member

    Jul 1, 2008
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    Actually, the cheesy look on your face didn't catch my eye as much as all that squeeze-out. You're going to hate yourself for not getting to it within 20-30 minutes of glue up. Blue painters tape is your friend!

    Now, onto your problem.. As I see it, the circuit's electrical details are going to be fairly typical, so the bigger question is how much of a purist woodworker are you? Do care how the LED array is going to marry with your wood work, IE; screwing surface mount metal or plastic fixtures to your work, or are you looking for a wood worker's solution like this? I show brass screws but the strip can be glued in with Plyobond or Silicone that can be pried up if needed.
     
  9. davidbenjamindix

    Thread Starter New Member

    Feb 25, 2010
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    thanks CDrive. great diagram. no worries on the squeeze out. my new favorite sander is a disc sander. it QUICKLY, and i mean quickly removes all of your squeeze-out with no problem. you start with 80 grit, and in the end, you really don't even need 220. 180 with disc sander does an incredible job. i was astounded on the little amount of time it takes to sand with a disc sander. generally what i do when i sand is use the belt sander, 45 degree left of grain, 45 degree right of grain, then straight with the grain. i do that with 80, 100, 150. then i move to 80 or 100 with disc sander and finish it up.

    i might actually end up using your LED diagram for the lid switch. thank you for that. and thanks everyone else, too, for the positive posts. all good useful information.
     
  10. Wendy

    Moderator

    Mar 24, 2008
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    If you use the diagram shown you will likely need at least 27 volts for the power supply. You can break the chains up into two or three groups. The few LEDs per chain, the lower the power supply voltage. For 12VDC power supplies (a popular wall wart value) you would need 3 LEDs per chain, no more could work, but you could use as many chains as you want, each with it's own resistor.
     
  11. CDRIVE

    Senior Member

    Jul 1, 2008
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    Bill,..actually, that diagram wasn't intended as an exact (I should have noted it) electrical diagram. That's why no voltage or R value was indicated. It was meant as more of a LED/Joinery suggestion. I'm glad you pointed it out though. ;)

    Chris
     
  12. Wendy

    Moderator

    Mar 24, 2008
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    No problem, always remember the guys learning the stuff tend to be very literal.

    This is an interesting project, I'm wishing the OP total success.
     
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