My 12-year-old daughter wanted me to make her for Christmas a Star Trek Klingon bat'leth sword prop to hang up in her room. So I made one from plywood. It's really a very simple project. The basic steps were: measure, make and print a template, cut out with jigsaw, paint with metallic paint, wrap handles with leather cord.

Consumables:

4'x2' sheet of 1/4" plywood (I used cheap pre-sanded birch from Lowes; make sure it's decently flat, straightening if needed)
glue (Titebond II)
metallic silver paint (DecoArt)
leather cord (or paracord or scrap leather)
paper (for template)
masking tape (for template)

Tools:

computer and printer
jigsaw with blade for curves
drill with hole saw (optional but makes inner holes easier)
scissors
paint brushes
woodworking vise (or clamps)
measuring tape
ruler
pencil
cloth
box-cutter

I also had a slip in the cutting process which required patching the wood. I ended up patching with JB Weld.

Confession: While this was a Christmas present, I only finished it by December 30.

Step 1: Measure

Bat'leths are sized by going down on one knee and measuring from the floor to the tip of the head. In our case, it was 45 inches.

Step 2: Template

I traced a bat'leth in Inkscape from a photo I found online, and resized it to the 45 inches that I needed.

Of course, I don't have a printer that can print something this size, so I overlaid a grid of 7.5"x10" rectangles, and printed out each rectangle as a separate page (shifting the drawing over in Inkscape as needed).

Here's the Inkscape svg file for my template. You'll want to resize the bat'leth to your dimensions, and then perhaps add more page-sized rectangles. To resize, load the template in Inkscape, click on the bat'leth itself, choose Object | Transform | Scale via the menu. Click on Clear. Select in (or a metric unit if you prefer) from the unit drop-down. Make sure Scale proportionally is checked. Put in your desired width. Press Apply. Then select the whole drawing (ctrl-a), and shift it around, printing one page at a time (you can see in Inkscape which area of the drawing will get printed), using the grid as a guide to make sure you're getting everything. (You may want to add more grid rectangles, too.)

Cut margins as needed and tape sheets together.

Cut out the template.

Tape to wood and trace with a pencil. (I then drew the lines where the tape was by hand.)

Step 3: Cut Outside

Cut the outer outline of the bat'leth with a jigsaw. Use a sharp and good quality blade (I used a Bosch T101AO) to give a smooth cut. I clamped the sheet to a work table, and cut, moving the sheet and re-clamping as needed. To avoid vibrations, don't cut too far from the table.

This was my first time cutting curves with the jigsaw, and it went very nicely, which I attribute to the good quality blade.

Step 4: Cut Inside

I used a 1.5" paddle bit to drill circular holes at the two ends of each of the areas, flush to the tracing, making sure that the bat'leth was clamped to a piece of sacrificial wood (to prevent a jagged edge on the bottom side), and then just joined up the holes with the jigsaw. If you are more skillful with a jigsaw, you could just drill a smaller hole and do the whole cut with the jigsaw.

(Unfortunately, the sacrificial lumber I used had a hole in it, which made the drill jump and one of the circles be really crooked. Luckily no one got hurt, and I ended up filling the defect in with JB Weld.)

Step 5: Sand, Prime and Sand

Sand carefully. I went to 320 grit.

Then I "primed". I'm cheap, so I just painted the whole thing with wood glue (Titebond II) diluted 1:1 with water. Then after that dried, I sanded it again. It was easy to make it very smooth at this point. I filled in some dents and small voids around the edge with undiluted wood glue.

Unfortunately my "priming" method didn't work that well with the acrylic paint I used later, which didn't adhere as well as I'd like. If I used spray paint, it might have adhered better, but I tend not to do well with spray paint.

Step 6: Paint, Paint, and Paint

I then painted several thin coats of DecoArt metallic silver. On the two sides, I used very long strokes with a foam brush, and I did the edges sometimes with a cheap small brush and sometimes a foam brush.

I didn't sand between coats except where the paint made drippy marks, because sanding would tend to remove the paint all the way down. (Not so great adhesion, I guess. Spray paint might have been better, but I don't have spray paint skills.)

Surprisingly, I used less than one of the 2 oz bottles.

I really like the DecoArt acrylic craft paints, and have been using them for about 10 years.

Step 7: Handles

I wrapped the handles in flat (about 1/8" wide) leather cord. Some rough calculations suggested I'd need about 35 feet of it so we bought a 50 foot spool.

More careful measurements suggest that a 5" wrapped handle requires 134 inches of leather cord. More for a larger bat'leth as the handles will be wider.

For each handle, mark off the 5" handle area, and put a generous serving of wood glue on the area (including the two edges).

Then do a tight spiral wrap, tucking the two ends of the cord under the spiral wrap. Work quickly so the glue doesn't set before you're finished so you can clean it.

Tucking in at the start is easy. At the end is a little harder. Make the last three loops loose, and pull the end through. Tighten the loops, and then cut the end. Shove some more glue in.

Wipe excess glue and clean the glue off the cord. (If you worked quickly, the glue wouldn't have set.)

Then clamp. I wrapped the handle with aluminum foil (so it wouldn't stick or get dirty) and put it in a woodworking vise for a couple of hours. Repeat.

Finally, I touched up a few areas of the paint which got scratched in the process or got some glue on them.