To Make a Scabbard for an SCA Rapier
Good scabbards for SCA rapiers are also pretty rare. This is how I make mine. Basically it's a leather cylinder (because SCA rapier blades aren't flat, like their historical counterparts.)
Start by measuring the circumference of the tip of the weapon you're working with.
Cut a strip of leather that's 1/2 to 1 inch wider than that circumference, and a couple of inches longer than your blade.
As a rule, you'll want something fairly stiff, at least 8 or 10 ounce leather. Alternatively, you can use a piece of PVC pipe inside the leather (I had to start doing this when I began using a Del Tin blade, because otherwise the balance was off and it wouldn't hang right.) If you're using the pipe, make sure it's longer than the blade, and that the leather cover is longer than both of them--the leather tends to shrink during while being worked, and it's much easier to trim a bit off the end than to have to re-do the entire scabbard because you underestimated.
Punch or drill holes along both long edges, spaced 1/4 inch apart.
If you want to dye the leather, do so at this point. You could probably tool it too, if your fancy runs that way. If you prefer the natural leather look, proceed to the next step.
Once the dye has thoroughly dried, soak the strip of leather in water so it's soft and pliable.
Start at one end and roll it into a tube so the long edges meet. Sew the edges together. The inside stitches should run lengthways, so they won't be cut by the blade sliding in and out of the scabbard.
The outside stitches go across the seam. I'm using red thread here for greater visibility; the actual stitching will be done with black thread.
While the wet leather is fairly pliable, once it dries, it will maintain its new shape.
6. To finish off the end, squeeze the tube together and cut it off into a curve or fairly blunt point. Punch a few more holes and sew the end together.
There are a couple of options for making the hanger. Historically, scabbards were hung from some sort of hook off of a ring on the belt. There are several nice pictures here: http://www.karlrobinson.co.uk/Gallery_hangers.html
The "quick and dirty" method is to cut a triangular or elongated "D" shape--at least six inches by twelve. Wrap the end around the top of the scabbard and sew it to itself. Mount some kind of hook at the apex of the curve. This is one of my older scabbards, showing that method. (When it wears out, I'll replace it with a nicer one.)
A more elaborate and historically accurate method is to make the "D" from a long piece of leather, folded over on the sword side. Typically these hangers were split into two or even three sections, as can be seen in the website linked above.
The folded edge is cut into a series of strips, to make loops which slide over the scabbard.
Cut carefully, to make sure the loops are the right size to fit onto the buckles, without being too wide or too loose. It's better to end up with a lot of scraps from cautious trimming than to ruin the whole piece by over-eager cutting.
The "buckles" are actually sliders that are used to give a friction-fit on the scabbard. To make the sliders, get several small buckles from Tandy (or wherever) and remove the tongues.
Slide them up the loops before inserting the scabbard.
Then slide them down the loops toward the scabbard to hold it in place.
Repeat this process with the other straps. (Note that the straps are slightly narrower at the buckle end, to make them fit better without losing too much overall width.)
All the buckles mounted.
Sew the two flaps of the hanger together. In this case, I decided to use red thread to make it more decorative. Functionally speaking, a single set of stitches is sufficient. I double-stitched this one to make it look better.
Before stitching the top point closed, you'll need to add the hanging hook. This can be a fairly simple hook sewn between the two sides of the hanger.
Or it can be a more elaborate mounting.