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Everything that could probably be said about this project has probably already been said on this page:

Really fantastic project, i'd never played with microcontrollers (uC) before, but it was so well laid out and explained I had no problems working it out, and it totally taught me the basics to go ahead and start my own project, the RGB LED x 3.  All the parts were purchased from apart from the LEDs which came from ebay. 

The one main self induced problem I had was the LEDs I bought were super bright blue with water clear housing, this means 90% of the light shoots straight out of the top. When you are looking at them from the side, you can just make out if they are lit or not but from the top they are blindingly bright. Unfortunately I was so keen to build the cube I didn't wait to find a solution for the light issue, which would have probably been easier to solve with individual LEDs rather then in a assembled cube! Anyway, I was experimenting with any diffusion method I could find or come up with. 1st was acrylic paint was rubbish, the paint didn't stick to the slick LED plastic and when I managed to paint it with persistence it dried very uneven and looked terrible.. The 2nd most obvious method was to sand them, but sanding 64 LEDs wasn't something I wanted to do, and once it was assembled, it would have been near impossible to get to the inner LEDs. 

I came upon the "straw method" also on the instructables website, well, to cut a long story short, i tried the straws and they were good. I worked out that if i could put a 1cm piece of straw on the LED and then fill it with something it would be perfect! So first i tried to fill it with pva glue but that didn't work because the glue shrunk and bubbled as it dried, i tried hot glue which was awesome, but too hard to make neat, and impossible to get onto the LEDs in the middle of my already assembled cube. Then I came up with the crazy idea to use paraffin wax! Anyway, i melted a tea light candle and used a straw to drip molten wax into the sections of straw i placed over each LED, and the result is fantastic!

Here are some photos and clip of it in action:

Some of the close photos of the details look quite scrappy, but from even an arm's length you don't really notice the imperfections.

I've added a shopping list of what I bought to do this project. The list has part numbers and current Australian prices as at 13 of April, 2009, from the shipping is reasonable I think it was only $4 for orders up to $50, but it does come from overseas so allow up to two weeks for delivery. In the list, I bought 2 "packs", a LED pack and a resistor pack, which are great value, but if you already have some odd LEDs and resistors you can probably leave them out, you only need 2 or 3 extra LEDs for status and power. Also, the project requires 16 x 220 ohm resistors which the "resistor pack" does not have enough of, hence the extra resistors, they're very cheap anyway. When i ordered the parts, i actually ordered enough to make 2 complete cubes plus some spares and it still came in under $50 (that's not including the stuff mentioned in the next paragraph).

Apart from what is on the list, you will the actual LEDs, 64 of them, your choice, however after what I went through, i highly do not recommend clear LEDs, get diffuse ones. Also you'll need a power adapter, i picked up a brilliant very small and light one from jaycar for about $15, 9v 500mA , i'm going to buy a 2nd one. Also a socket for the power adapter to plug into, i just got that from jaycar while getting the adapter. Also you'll need some sort of hook up wire, if you work in IT, go to your comms room and find where they've done some repatching, they aren't allowed to reuse wire cut to the patch panel, they chuck it out and cut new wire, so I've taken rolled up piles of patch wire out of the bin and it is perfect as general purpose hookup wire. 

You will also need a programmer which is a little bit of a bummer if you only plan to make one project, but could also be used to motivate you into doing more then one. I just got the cheapest one i could find on ebay, it is based on the USBASP design and all the tools used are open source, which is great. 

If you are starting COMPLETELY from scratch, you'll need a soldering iron, some solder, some small wire cutters, a small needle nose plier came in very handy and a multimeter is handy too, but not essential i suppose as is a magnifying glass or loupe for checking your soldering work. The second board I was making, i soldered the little reset switch in wrong which was causing the uC to not start up,  i don't think i would have figured that out without my multimeter. 

Various unsuccessful diffusion methods tried :

Subpages (1): 4x4x4 shopping list