3x3x3 or 4x4x4 LED cube

I would like to build a 3x3x3 or 4x4x4 LED cube. I can not find a schematic and codes for it. I have google it and found some which are in www.instructables.com. I am not member of it. I was hope someone could share it with me. Also, I need to know what kind of LED should we use. The cheapest I can find LEDa are in Allectronics.com. Does anyone have use this company before or are there other place that might be cheaper?

Reid

Having built a 5x5x5 blue led cube I can state the most important led attribute is that you use diffused types. These give light off in all directions and make a much better presentation then some of the brighter non-diffused leds that focus their light into a narrow beam.

As far as best price, it's hard to beat the prices that asian sellers on E-bay offer. I was getting 100 blue 5mm diffused leds for around $15. Takes about 10 days delivery to west coast US.

http://business.shop.ebay.com/i.html?_nkw=diffused&_sacat=66954&_odkw=blue+diffused&_osacat=66954&_trksid=p3286.c0.m270.l1313

Lefty

Lefty,

Wow I did not realized LED on ebay so cheap. Can you share schematic and codes? I might want to build 5x5x5. Also which chips and which value on resistors do you use?

Reid

Can buy more locally also, faster/cheaper delivery. http://www.dipmicro.com/store/index.php?act=viewCat&catId=511 Buy 100 for $5, about $2.50 shipping, lots of colors. The extra bright ones need very little color to be very bright.

I've read that non-diffused LEDs can be lightly sanded to achieve a diffused look.

CrossRoads, you beat me to suggesting dipmicro ]:D

I'll have to say bad things just to appear helpful. I have all their bright 5mm LEDs, all colors. They're extremely bright but yes they are clear and not diffuse. I wish I had lefty's suggestion before I shopped for leds.

Here's my results with their LEDs (5mm, clear, POV display):

http://www.dipmicro.com/support/showthread.php?tid=132

As you can see, the center is very much brighter than the side. If I had diffuse ones, I'd be slightly more consistent at different angles.

Can you take some fine grit sandpaper, like 320, and lightly sand the LEDs to make them look more diffused?

I'm also thinking about making a nice led cube, I already have 15 TLC5940, so I will use pwm in it, my biggest doubt right now is what sort of wire do you use to make the cube, I read somewhere that they use metalic wire, but where to source it? Wire wrap wire that is usually used to make my ugly bread boards is to thin and fragile. Maybe 1mm solid cooper wire is good?

http://www.instructables.com/id/LED-Cube-with-Arduino-and-custom-PCB/step2/Cube-Construction/

This was constructed using 20 gauge steel wire.

microguy: Lefty,

Wow I did not realized LED on ebay so cheap. Can you share schematic and codes? I might want to build 5x5x5. Also which chips and which value on resistors do you use?

Reid

I didn't create my own schematic, but rather utilized the one in this web based project. I doesn't use resistors to control led current, rather uses special constant current shift registers to control led current.

http://picprojects.org.uk/projects/lc/index.htm

Lefty

tomm:
http://www.instructables.com/id/LED-Cube-with-Arduino-and-custom-PCB/step2/Cube-Construction/

This was constructed using 20 gauge steel wire.

But where can I buy some of it?
Sorry for this “stupid” question, but sourcing wire in Portugal can be a bit difficult.

I'd say most hardware stores should carry various types of wire. If not, try eBay?

Not here lol. I can get cooper wire for household installations, and then cat 5/6 wire for ethernet, wirewrap is difficult to get, almost no one as spools, and then they just have more household wires in multifilar/stranded flavours.

Maybe 1mm solid cooper wire is good?

My experiance is you want metal wires that are stiff so they will not bend as you build up and solder each level on. Anything that takes away the 'squarness' of the completed cube will look pretty poor in presentation. I used 1.8mm solid brass rods for the support wire. Smaller diameter might still be OK as brass holds it's shape pretty well, copper is too soft in my opinion. Steel wire might be difficult to solder to. Tin coated copper bus wire in larger gauges might be ok, but still might bend to easily. Designs that just utilize the LED wire leads as verical support structure are very vulneable to bending out of shape and then very difficult to bend back to precisely straight.

Lefty

The hipnocube says that they use 0.7mm galvanized steel wire. Yes, cooper is a bit on the soft side. Was it difficult to solder to 1.8mm rods?

Was it difficult to solder to 1.8mm rods?

No, brass is very easy to solder to. I do have a temperature controlled soldering iron and I'm sure that helped.

Lefty