Magnetic table lamp

I wanted a new table lamp, but found a regular table lamp rather uninteresting. I wanted to create a lamp with which it is possible to readjust the shape and size.

The table lamp exists out of eight cubes, with which you can build different shapes. Each cube has four bright 0.5 watt straw hat LEDs inside.

This lamp was easy to make, but consumes a lot of your time.

The light output depends on the total amount of cubes that you use. If you use just one cube you have little light (for example as a night light), if you use all the cubes you have more than enough light to light up a room.

The overall cost of this project was low, except for the neodymium magnets (40 $), which seem to have risen in price the last year.

Step 1: Materials and tools

Materials:

• 40   0,5W straw hat LEDs 
• 8 bridge rectifiers
• 8   6.8 Uf  > 12v capacitors
• 16   39 Ohm 1W resistors
• Perfboard
• Conductive silver
• White acrylic sheet
• 192 nails
• 192  6 mm by 5 mm round neodymium magnets
• 12v power supply 2 amp
• Toggle switch
• Wooden board (9 mm thick)

Tools:

• Wood glue
• Super glue
• Jig saw
• Miter saw
• Sand paper
• Wood clamps
• Drill
• Drill bit  3 mm, 6 mm
• Hole saw 67 mm,  74 mm
• Solder
• Solder iron

Comments

[decfootylad]

i wondered where the wires from +ve and -ve corners go, on the mini pcb's inside each cube.

[Kirgdeking]

Hello, I have a question: instead of the acrylic sheet, can i just use a 2mm PVC sheet of plastic as i am on a low budget?

[mganpate]

its very nice project kindly send us pdf pls pls on [e-mail].

[Saakaszwili]

Hi
Your project is so awesome that i decided to take it, althought i have no experience in wood or elektronic work. I've got one question, what was the thicknes of the acrylic scheet ?
Thanks in advance

[HHarry]

Thanks
The acrylic sheet is about 3 mm thick.

[Cupofblack]

This is pretty awesome. Sorry if this question seems obvious, I'm new to circuits:

Do the magnets have an effect on the current, and is that why you alternate them? And if they do, does it matter what how you orient them?

[Stoffo]

Hello! Thanks for your comment on the magnets, this has made things easier.
One question remains though: I'm having trouble finding the good LEDs required for this project. You said: "0,5W straw hat LEDs", but I'm finding many different LEDs with all different lighting strengths. Could you possible give a link or name of the type of LEDs you have used? Or maybe the amount of lumen emitted from these LEDs?

Thanks in advance,

Chris.

[HHarry]

These are the LEDs i used: http://www.benl.ebay.be/itm/220649093432?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 

But feel free to use any kind of led you want (resistor value have to be recalculated).
I used these straw hat LEDs because of its wide angle and high output.  

[mxmega]

Hi,
A question regarding the circuit.

I can't quite understand how it works.In the picture, i see only 2 legs of the rectifier in picture of step 5 whereas in the picture in step 1, the rectifier has 4 legs. Are 2 of the legs cut off?

Also, does the capacitor used needs to have polarity for it to work?
Are both the resistors connected to the one leg of capacitor, and if so, does the other leg of capacitor connect to the rectifier? Because I can't see where the the parts are connected together.
Finally, when soldering the circuit to the cube, are all 4 of the legs shown in diagram at step 5 connected somewhere? If so, where?

I'm a complete newb in electronics, and if you can clarify this I'd be forever grateful.

Btw, awesome ible :)
thanks in advance

[curious youth]

hi incredible ible !
im from aus and having trouble tracking down the magnets with the right dimensions. and suggestions for me as i really want to make this lamp. its great :)

[HHarry]

Thanks!
have a look on ebay: http://www.ebay.com/sch/i.html?rt=nc&LH_PrefLoc=2&_nkw=magnet%206%20mm%20x%204%20mm&_fln=1&_trksid=p3286.c0.m283

I got my magnets here: http://www.supermagnete.be/eng/magnets.php?group=discs_small 

[curious youth]

Cheers ! as soon as i get all the money togeth (im on a student budget) this will be the stand out in my room. im going to work on making it a standalone lamp that i dont need a desk for. ill post pictures when i finish (who knows when that will be though)

[Stoffo]

Hello! A very nice project indeed.
I'm planning to try this myself, but I have one question regarding the magnets. Is het neccessary to have this exact dimensions, or can you do with anything a big smaller or less tall?
With other words, do you know how strong the magnets have to be, so that all arrangments are possible and the cubes don't fall down?

Thanks in advance!

[HHarry]

You could change the magnet size. My magnets can hold 1,2 kg each. I find this necessary when you add more magnets to the sides.

[jlundquist]

what would this look like if the whole cube was made from the acrylic instead of wood? would the wires and circuits show through as shadows?

[HHarry]

Yes the shadows would shine through. But maybe you could put sticks in the corners pointing to the middle where the circuit and the leds could be, so the light is not obstructed by the wires.

[anglerfish]

This is a wonderful idea. Perfect gift for my college bound kid to use for his dorm room. I am going to try this one.

[HHarry]

Tanks!

[Penolopy Bulnick]

That's amazing!

[HHarry]

Thank you!

[rock0911]

I don't know that why there is a bredge rectifier.
did you mine your connections have AC all the time?

[HHarry]

I used a DC power supply. The bridge rectifier is placed in the circuit to make sure it does not matter which way you place the cubes together.

[Mr. Boo]

What are the specs for the bridge rectifier? When I look them up online I see many different types.

[HHarry]

Almost any rectifier would be fine, but over 2 amp  is just overkill for this application. I used this one: http://www.ebay.com/sch/i.html?rt=nc&LH_PrefLoc=2&_nkw=W10M%20bridge&_fln=1&_trksid=p3286.c0.m283

[Mr. Boo]

OK, thanks for the info!

[jlundquist]

How do you make the sixth side power the cube?

[HHarry]

The sixth side is a bit tricky.
I used two methods:
The first method is soldering short wires to the nails inside the box and then to the single nails of the leftover square, finally glue the cover to the box. This is the best (recommended) method.
I started the second method after I finished five cubes. I call it the fast non-professional I just want this project to be done (not recommended) method. It goes like this: put the nails in the leftover square and glue it to the rest of the box. I was lucky to have a voltage on every nail.

[jlundquist]

Thats what i had in mind. also ive decided to tackle this project. but its my first time doing circuit work. any pointers? i comprehend the rest of it all even the wiring but as far as making a circuit i dont know anything.

thanks for the great project!

[lanternfish]

Hi jlunquist

If you look closely at the last image in Step 5 you will be able to make out how all the nails in one corner are soldered together and then connected to either +ve or -ve.

Does that help?

Cheers

[alexandrelandim]

Very nice post, HHary. I live in Brazil and I like to read instructables, but never done one project. This´ll be the first one. Congratulations!

[HHarry]

Thank you and good luck!

[xprosario]

Very good project!
Sorry, but I know very little about electronics. I can ask a question: What is the task of the capacitor?
I did a simulation and the voltage drop is very evident in the brightness of the LED. What might that be?
Thank you very much.

[HHarry]

Thanks! The capacitor is not strictly necessary, i just put them in the circuit for smoothing out the voltage and to catch some voltage spikes.

[xprosario]

Thanks for your answer!
In what may be the voltage drop? Surely it is the bridge rectifiers.
I have to find a resistance that allows all LEDs glow like that, as from the fourth cube at a low light.

[myyrhdyn]

This is amazing, going to try it as soon as I can. Thank's

[HHarry]

Thanks!

[profpat]

very nicely done!!! great project!

[HHarry]

Thanks!

[mxmega]

So cool!
Love the design!
Makes perfect gift to someone

[HHarry]

Thanks!