I've been meaning to post this instructable for a while but now with a woodworking contest I have more incentive. My son cosplayed as the Blue Spirit from The Last Airbender series and this is my take on his double broadswords.

Step 1: Tools and Materials

Tools

Jig saw or Coping saw
Chisel
Plane
Drill
Dremel (optional)
Electric sander (optional)
Small spring clamps

Materials

Two 48" x 4" x 3/8" poplar planks
One 3 1/2 " to 4" round unfinished wood plaque
Paracord (color of your choice)
Two bead spikes
Wood glue
One flat 3/8" wood dowel at least 8" long (the width should be the same as the depth of the wood plaque)
Two small wood dowel pins
Wood filler
180 grit sandpaper
Metallic gold spray paint
Metallic chrome spray paint

Step 2: I'm Seeing a Pattern

We are making a full tang sword, meaning that the blade goes completely into the shape of the handle. So take this into consideration when deciding on a pattern and shape of your sword. Draw your pattern onto your poplar planks and, using your jigsaw or coping saw, cut them out. You could draw your pattern on one plank and cut it out and use that as a stencil for the other sword.

Step 3: The Butt End

For the pommel of the sword, I traced the bottom of the swords ( about 2 inches in length) on the scrap pieces of poplar and cut them out. You will need 4 of these. Glue them to the bottom of the swords and use the spring clamps to hold them in place.
When dry, fill any gaps with wood filler.
Drill a hole to fit your dowel pins at the bottom of each pommel and sink and glue the dowel pins in them.
On the protruding end of the pins glue your spike beads.
Sand and shape your pommels.

Step 4: The Razors Edge

At this time I decided to put an edge on the swords. Using the plane I shaped the edge of the swords, keeping 6 inches from the pommel untouched for the handle. You can keep from planing into the handle by making a notch at the established top of the handle. I then sanded the blades smooth.

Step 5: Hilt! Who Goes There?!

For the hilt you will take the unfinished wood plaque and cut it in half. This can be accomplished easier if you find the exact center of the plaque. I accomplished this by drawing a square in which the round plague fit perfectly in (edges of plaque to lines of the square) and drawing a diagonal line from opposing corners of the square.
You will then chisel a recess (3/8" depth) in the center of each half that will accommodate your sword.
Cut 2 lengths from your flat dowel the same length as the diameter of your plaque.
Glue a half plaque to each sword. Remember one sword will have the plaque glued on the left side of the edge of one sword and the other to be glued to the right side of the edge of the other sword.
Take a length of the flat dowel and glue to the opposing sides of each plaque.
When dry and set, sand the ends of the flat dowel to the shape of the plaque.
Take this time to fill any gaps with wood filler and sand when cured.
Match your two swords together and they should look like they form one sword. You can start tweeking at this time (sand here, filler there, etc) so that you achieve this effect.

Step 6: Time for Paint

I started with painting each blade with 3 coats of chrome paint.
When dry, I wrapped the blades with newspaper and painted the hilts and pommels with 3 layers of gold.