This is my generic guide for making a simple sword scabbard. I will be using my Sword Art Online sword scabbard pictures as references. I normally always make the scabbard after I have made the sword. This helps to ensure that I can fit the scabbard exactly the sword.
The main materials I use are 1/4″ Birch Plywood, wood glue, and black felt fabric.
The first step is to lay your sword down on to the plywood and then draw out a patter about 1/2″ to 1″ around it. You will need 2 copies. Next, cut out some walls, which should be about 1/4″ to 1/2″ thicker than your sword. You should end up with something similar as pictured below.
Test fit your swords before you start gluing the parts all together.
Now apply wood glue onto the edges of the walls and clamp it together to the base. A side will be joined fairly well after about 30 minutes of clamping, so you can move on to the other walls in quick order. It should be left to fully dry for a few hours after you have glued the walls. Do not glue the top part yet.
Next, I line the insides with black felt fabric to help protect the sword. Use whatever color of fabric that best suits your sword. I used E-6000 to glue the fabric down to the wood. When you glue the fabric to the top part that hasn’t been attached yet, be sure you leave room for the walls to be glued to. Once the fabric has all been glued, you can then use wood glue to attach the top piece off wood to the rest of the scabbard. Take note of the gaps at the intersections, this is alright. I will fix these up with bondo after I use my router to round the edges.
Next, I round the edges with my router.
I did not remember to take pictures for the next step. But you will want to fill in gaps with bondo and then sand it smooth. At this point, you have a very basic and generic scabbard. It is now up to you to add details and paint it the correct colors. Here is an example of some pieces I added to the tops and tips, courtesy of my 3D printer. You can attain similar results with styrene and a heatgun.
Once it has been painted and most of the details added, you still need a way to hook the scabbard to your costume. I use picture frame hooks with 1/4″ wood screws and washers. The 1/4″ wood screws are usually too long, so I use about 2 washers as a buffer. I then wrap it with either real leather or pleather to hide the hooks. This is then glued down with E-6000.
And the final result should be something like this: