I got around to making an actual instructable. That's a big thing, I usually just post pictures of finished projects. Part of the reason I'm making an instructable is because this sword was actually done when I started (thus the name "Frankenstein"). Then it broke, and I decided that when piecing it back together (remaking it), I would take pictures and turn it into an instructable. The original version of this sword is pictured here: https://www.instructables.com/id/Ninjato-20/

As you've probably taken from the "2.0" bit, I have another ninjato that is "1.0", and a 3.0 dagger. I'm working on getting pictures of a new 2.1 into a suggestable (suggestions, not instructions, aka pictures). Every weapon is unique, however, so it's a bit hard to categorize them.

Here's a more in depth explanation of the different "models" of swords: 2.0 swords (this one included) are harder than the 1.0 and 3.0. However, they are much thinner than the 1.0, and the blades look significantly better. In some cases. The long sword 1.0 is pretty regal, but maybe that's just nostalgia. It was Laertes's sword in our production of Hamlet. It all depends how you make it. On the matter of plays, the 2.0s make better stage props: harder, slightly, but more realistic. The 1.0s are better for smacking people. 3.0s, can be carved to look all fancy, and though they're pretty firm, they're lightweight and made of foam, so they're best for LARP.

Suggestions are more than welcome. If you don't understand something, or I missed something, by all means, say so and I'll try my best to help. Comments and pictures of what you've made from this instructable, with explanations of what you improved upon are certainly helpful. Ratings are useful feedback no matter what number of stars you choose. My main goal is to help other people make this - and maybe even help me improve my own swords.

In any case, here's my first try at making a full instructable.

UPDATE: This sword is actually kind of out of date now, so you might want to check out my latest weapon-making methods here.

Step 1: Materials and Tools

Lets see how well I can replicate this... I might miss a few things, since I made the cardboard part of the blade before the rest of it, but nothing essential. In any case:

Essential Materials:
Cardboard (preferably a long piece with the grain parallel to the longer side - this makes it stronger. Also, the thinner and stronger the cardboard, the better. Be aware, though, that the words "thinner" and "stronger" are often rather contradictory when working with cardboard)
A flat wooden rod (the thinner the rod, the weaker, the thicker, the thicker the blade. I used one that was five millimeters thick and a half an inch wide)
Rubber foam weatherseal (which I will call foam tape)
Masking tape
Electrical tape
Foil tape
A foam sheet (It should be around 5mm thick with almost invisible cells. You'll find this at an art store - I got mine at Michael's. I think it's called craft foam)
A different foam sheet (This kind you'll find in shipment packaging - it's thinner and more pliable than the craft foam, and you can see the cells. It's good for grips - so that's what we're using it for)
A spacer to make the handle the right size (I used a cut up wire hangar with around four handle length pieces wrapped together with shrink wrap)

Optional Materials:
Decorative Tape (I used purple duct tape - This is optional)
A wire hangar (for the spacer)
Shrink wrap (also for the spacer)
Double Sided Tape
Lanyard/Scoubidou thread (for the grip)

Tools:
Scissors
Pencil
Box knife
Pocket knife (with a saw)
Ruler (or straight edge, though a ruler can come in handy)

NOTE: If you wonder why my cardboard blade is shiny silver, just stop wondering until I mention foil tape again. That's one of the drawbacks of having this thing be remade instead of new.

Step 2: Making the Blade

This is the most complicated step - and unfortunately, I don't have any pictures of doing it.

Now is the time to figure out the dimensions of your blade. Mine is one and a third inches wide and 25 inches long.

Take a piece of cardboard, and trace a section of the cardboard that is twice the width that you want your blade to be. Trace it so that the long lines are parallel to the grain - this is important, it makes the blade stronger and it'll save a lot of work later when you have to fold this piece in half. Carefully cut this out using an improvisational combination of scissors and the box knife.

Now comes the hard (read: frustrating) part - time to fold that strip of cardboard in half. It helps to mark out the middle with a pencil (make sure you're exact). You might even want to take the box knife and cut slightly into the cardboard (just don't puncture through the covering on the other side), something I did.

Once you've got that folded, cut off the edge that's going to be the "tip edge". This part is easy: just make sure you figure out what you want the tip to look like first.

HELP WANTED: If you take pictures while doing this step, you can post them in the comments and I'll put them up on this step so that people can see what to do.

Step 3: Preparing the Blade for the Tang

Line the crease line on the inside of the blade ("inside the sharp edge") with foam tape.

Cut out enough strips of packaging foam to cover the foam tape.

Tape those foam strips to the inside of the blade as seen in the pictures.

Step 4: Attaching the Tang to the Blade

I know, I know; on a real sword, the blade and the tang are one piece of material, and this is a little weird. But it works.

Get out your wooden rod and place it inside of the blade as seen in the pictures, with the thin side facing out and the rod resting on top of the foam.

Even up the wood with the open side of the blade and tape (with masking tape) the two sides together. Leave a little space for the tip where there's no wood (I didn't leave enough). Make sure to press the wood into the tape so that it stays in place, and make sure to tape the sides together tight (secure). Start by taping at intervals, and then eventually cover the whole side with tape.

Step 5: Finishing Up the Blade and Tip

The tip:
Press the edges of the tip together to form one edge and tape these together.
Cover the tip edge with foam tape for padding.
Finishing the blade:
Now - finally - cover the blade with foil tape. This gives the blade a metallic feel and look. This step is tricky, because the tape tends to crinkle up. Foil tape has a non stick piece of paper covering the sticky side like they have on double sided tape, and you want to be very careful while peeling this off to mitigate wrinkles. What seems to work best for me is cutting out lots of six inch pieces instead of using only a few pieces the length of the blade. No matter what you do, though, there will be some wrinkles.

Step 6: Making the Guard

Take a piece of craft foam, the kind you get in an art store, and cut out a piece that's just a little bigger than you want your guard to be. Trim off the rough edges.

Cut out the middle of the guard and carve out a hole in the middle that is the width and thickness of the blade. Slide the guard over the tip and down to the bottom of the blade, just above the tang.

Tape the underside of the guard to the tang, as seen in the pictures.

Step 7: Cutting the Tang to the Right Size

Figure out how long (approximately) you want your handle to be. Mine is nine inches. Mark the spot on the tang that is nine inches (or however many inches you want your handle to be) away from the bottom of the blade. If it seems to long, adjust it.

Find a way to cut the tang off at the marking. I started out with a box knife, since the option of using a saw was, at the time, unavailable. I quickly figured out that unless I wanted to spend the rest of my life sawing through a piece of wood, I would have to find a different method. I decided I would try a pocket knife saw. Yes, a pocket knife saw; supposedly one of the most useless tools you could have - the dullest sharp thing in the history of sharp (Or at least that's how it works on my pocket knife). But it does work: dull as it is, the serrated edge helps tremendously. Eventually the excess tang just breaks off on its own. BUT WAIT: Keep the extra bit of tang, you'll need it in just a moment.

Step 8: Preparing the Tang for the Handle

This step is harder to document because it takes a good deal of improvisation. You're going to tape the sawed off piece of tang back on as seen in the pictures, with a "spacer" between it and the blade's tang. You can really use anything that's the right size as the spacer (see the pictures for ideas on the size), but I used a cut up wire hangar from a failed part for a past project and some saran wrap. The hangar was cut up into pieces around the right length and wrapping four of them together in saran wrap made a spacer that was the right size and quite strong. I taped the spacer to the tang, and then taped the sawed off piece to both of those, as seen. This mad the "core of the handle" the same width as the blade. Saw off the excess bit of the "core".

Step 9: Making the Handle

Cut out two strips of craft foam that are roughly a quarter of an inch wider than the handle's core and the same length as the handle. Tape them to the handle core as seen in the first few pictures, and then cover the entire handle with tape.

Cut out a fairly large piece of packaging foam (you can see the approximate size in the pictures). Straighten out the edges by cutting off the rough parts.

Tape one edge of the packaging foam to the handle right next to the piece of craft foam. You can do this next part in any order: Cut off the excess packaging foam so that it's the same length (but much wider) as the handle. Tightly wrap the piece of foam around the handle going one time around. Cut off the excess foam and smooth out the edge of the remainder.

Line the wide edge of the foam with a piece or two of masking tape, covering the entire edge and sticking off of it about halfway. Wrap the foam around the handle once, so that the edges of the foam meet each other. Seal the foam on with the masking tape sticking off the edge.

Step 10: Finishing the Handle

Finishing the handle:

To protect the foam from ripping, cover the handle entirely in tape. Unless the scoubidou thread you are using is not clear (and one of my colors was), be aware that the tape you cover the handle with is going to be seen when the sword is done, so you want it to look good. If you aren't using scoubidou at all, I like electrical tape because it has a nice feel. If any of your scoubidou is clear, colorful tapes, like colored or patterned duct tape or (I need to try this) reflective tape look great. If you do by any chance try reflective tape on your sword, post pictures. I want to see how it looks.

Cut out a piece of packaging foam that's a little smaller than the bottom of the handle. Put a piece of double sided tape on one side of it and tape it to the middle of the bottom of the handle. Take another piece of whatever kind of tape you're using and wrap it around the bottom of the handle, sticking out just a little bit. Fold the bits that are sticking out over the bottom of the handle.

Cut out a chunk of craft foam that's roughly the same size (it can be bigger, but not smaller) as the bottom of the handle. Using the bottom of the handle as a guide, carve the chunk of foam into the same shape as the bottom of the handle. Using double sided tape, tape it onto the bottom of the handle.

Step 11: Decorating the Handle

The first thing you want to do is figure out what colors and design you want your handle to be, and make sure you like it. You'll be wrapping your handle in various colors of scoubidou thread, and depending on how much you like cutting, you'll be making a pattern of some sort of stripes. I wrapped mine in ten stripes, alternating between clear and black scoubidou. The more often you switch colors, the more cutting you have to do. To get a better idea of what kind of design you'll end up with, you can look at the pictures.

The first thing you do is wrap a single piece of clear double sided tape around the handle up right underneath the guard. Peel off the covering, and begin wrapping your first color of scoubidou around the handle as seen in the pictures. When you've completely covered up the first piece of double sided tape, add another right where your about to wrap, and keep wrapping until you run out of that. To switch colors, simply cut the scoubidou piece free and stick a new piece of a different color right next to the first color and continue wrapping. This is easy (though tedious) to do and hard to explain, so I suggest you look at the pictures for a better idea of what to do.

TIP: To get stripes of equal size, wrap each string around the handle an equal number of times. The last stripe might look a little different, but I think it's worth it. I was lucky on that point though: My last string was only wrapped around one less time.

WARNING: If you're indecisive about what pattern you want to have, try to visualize different ones. DON'T try it out and then take it off. That takes a long time, and when you peel the scoubidou off, one side will be all sticky, and it wont look as good when you put it back on. Believe me, I tried it.

Step 12: Finishing the Guard and Cleaning Everything Up

This step is simple, and you don't have to do half of it unless you (like me) ended up with a bit of sticker on the guard.

If you do have sticker to deal with, peel off as much as you can by hand. When you can't get off any more, take a box knife (or something like that: sharp but not too sharp) and carefully shave the sticker off. You can do this before or after the rest of this step. I did it after. I suggest before.

Cut out a piece of electrical tape that's one of it's own width longer than the handle's diameter from front to back (the two wider sides). Carefully cut it in half so that you have two skinny strips. Put them on either side of the handle, on the guard. Repeat this process using the diameter from side to side and place the pieces of tape on the uncovered sides of the guard next to the handle, creating a rectangle of electrical tape around the handle. To cover up the inside corners of the rectangle (since the handle is an oval, there's a little bit of space between the corners and the handle), cut out triangles of electrical tape that are a little larger than the inside of the corners. Put them on top of the corners. You can see an example of the finished rectangle in the photos.

Repeat the process for the blade, creating a rectangle of electrical tape on the guard around the blade. Take another piece of electrical tape and wrap it around the bottom of the blade right above the guard. Once again, there's pictures that show what this looks like.