In this Instructable we will learn how to take an ordinary Lego octopus and make it awesome with glowing LED lights. This is a relatively easy project but a few tools are involved. We will be soldering and using a Dremel to carve the piece out and to create eye holes. I estimate that this project cost me $11.00 and took about an hour and a half to build.The price was a base cost for supplies, I am assuming that you already have the tools.

There are a number of uses for such an art piece. Ms. Zoid is already using this one as a necklace (I barely got to play with it).

Uses For An LED Octopus:

Costumes - Steampunk, Pirate, Sailor, Mermaid, Cthulhu
Hats - Hatband
Jewelry - Necklace, Hairclip
Nightlight
Kids toy - Hey, wait a minute.
Just a rad Lego

Items Used:

Lego Octopus - $5.00+ - eBay
2 RGB 3mm LEDS - $1.00 - Radio Shack
2032 Battery Holder - $2.99 - Radio Shack
2032 Battery - $.25 - eBay
Wire - You can use about anything lying around

Tools Needed:

Dremel Rotary Tool + High Speed Cutting Bit and 3mm Drill Bit - any drill would work
Soldering Iron + Solder - there's no substitute
Wire Clippers - to clip and strip the wire
X-Acto Knife - or sharp knife
Sharpie Marker - it was in my back pocket
Hot Glue Gun - again, lots of glues will work
Safety Glasses - I know you have these

Step 1: Lego Octopus Surgery

In this step we will prepare the Lego Octopus for surgery by carving out its insides and creating the eye holes. We will be using the Dremel Rotary tool for this step so be sure to wear gloves and safety glasses. You can also use a clamp in this step to keep your hands clear and away.

Clean out the cylinder of the Octopus with the high speed cutting bit (photo #1).
Cut the square piece flush to the rest of the octopus (photos #2 & #3) using your X-Acto blade.
Remove the last piece, cutting as far down as possible, using your X-Acto knife (photo #4).
Drill out the eye holes as centered as possible (photo#5). This is where the LEDs will go.
Remove all loose debris.

Carving the octopus as close to the sides as you can assures that the bulbs will slide in and be visible from the front. Do not carve so close that you create holes in the side like I did on my first attempt, these Lego Octopus Mini-Figs are getting expensive.

Step 2: Inserting the Eyebulbs

This step explains how I inserted the LEDs and set them up for the next step. It's a simple process but still be sure to line them up well and check your polarity. I had a battery close at hand to make sure that the LEDs work and that I didn't damage them. The first set I tried, I blew out the blue component and had to replace the bulbs. This was after I glued, so I had to cut the whole piece out.

EyeBulb Surgery:

Insert the LEDs into the holes you drilled in the last step. Do they fit well? Excellent! If not, drill slightly until you get the desired fit.
Mark your LEDs for polarity. In my case I used a Sharpie to mark negative (- or short wire) side for reference (photo #2).
Wrap the matching wires together ( -/- & +/+ repectively) while the are still inside of the body. This insures that when you remove them that they hold their shape (photo #4).
Press the LEDs firmly into their sockets (photo #5).
Test to see if your lights still work.
Using your battery holder, make sure you are still lined up for the final steps.
Time to glue your eyebulbs into place using the hot glue gun. You shouldn't really need that much glue for this part, just enough glue to set them in.

Step 3: Wiring and Soldering the Lego Octopus

This step is a little more complicated and I learned a few things (which is always great). For one, I could have wired this more efficiently. And two, this solder is much more rigid than I expected. This is my second attempt at this project and I have ordered more octopi and plan to build more of these as I have received a ton of interest from my facebook friends.

Be sure to stay tuned.

Soldering:

Cut two small pieces of wire at about 3/4 of an inch.
Wrap one each to each set of your LED wires and solder them well (photo #2).
Next test your battery and battery holder to ensure that everything is working and that you have the correct polarity.
Now solder your wires to the battery holder (photos #5 & #6).
Once you have a solid connection, you can press the battery holder down onto the octopus. The connections I made were strong and held in place really well. There was no need for additional gluing.
Slip the battery in and you are good to go. Removing the battery acts as the off switch.

You now have a functioning Lego Octopus LED Light. What's next? I thought, once I am able to pry it out of Ms. Zoid's hands, I can make something else cool. I'm going ahead and taking my time and wait to see what she creates with it. In the meantime I'll make another and post updates in this same Instructable.