How to Make a Homemade Kydex Knife Sheath

Even professional bladesmiths avoid making sheaths. Designing a sheath is tricky. It must have a snug enough fit that the knife will not simply fall out, yet be loose enough for you to draw the knife with a smooth, quick motion when needed. Kydex, a low-temperature, heat-forming plastic, is one solution if you need to produce a durable, good-looking, fitted sheath.

Things You'll Need

• * 2-inch by 4-inch by 12-inch block of closed-cell foam
• * 2-by-4 lumber
• * Hide glue
• * Sheet metal shears or band saw
• * 1/8-inch Kydex(R) 6 by 24 inches
• * Heat gun or propane torch with fan tip
• * Heavy leather work gloves
• * Wraparound eye protection
• * Power drill or drill press, 3/16-inch bit
• * Quick rivets
• * 80 and 120-grit sandpaper

Instructions

1. Measure your knife blade. If you do not already have one, assemble a pressing block by using hide glue to attach closed-cell foam to a 2-by-4 block of wood as long as your blade. The pressing block will allow you to form the Kydex without leaving tool impressions in it. Allow the block to dry overnight before using it.

2. Use sharp sheet metal shears or a band saw to cut a rough outline of your knife sheath from Kydex. Sample knife sheath outlines are available at KnifeForums.com after you click on "Designing, Making, Maintaining and Showing Off Our Knives » Sheath Making and Leather Craft 101." The belt loop section needs to be at least 4.5 inches long. The blade-covering portion should be one inch longer than the blade and twice its width, plus an extra inch. The extra space is for rivet placement.

   Your first piece of Kydex will look like a long rectangle with a shorter rectangle attached below it, with the left sides flush and the right side of the top rectangle extended several inches past the right side of the bottom rectangle, as seen by the viewer. Refer to the Kydex Sheath tutorial in the Resources section for diagrams.

3. Don heavy leather work gloves and wraparound eye protection. Turn on the torch with the fan tip, according to manufacturer's instructions. Adjust the flame. Heat blade portion of the Kydex just enough to allow it to fold, without scorching. Use the pressing block you made in step one to fold and form the Kydex around your blade. Once the blade portion cools, heat the belt loop portion of the Kydex and fold it over to form your loop.

4. Use your shears or band saw again to cut your sheath to shape, leaving at least 1/2-inch around the blade for rivet placement. Use a 3/16-inch drill bit in your power drill or drill press to make your rivet holes, as shown in the tutorial diagrams.

5. Attach quick rivets according to manufacturers' instructions. Quick rivets are available at leather-working supply houses. Sand the edges of your Kydex sheath with 80 and 120-grit sandpaper to remove any burrs.

Tips & Warnings

• See the Meg Smith tutorial in the Resources section of this article for diagrams.

• Knife aficionado Kyley Harris uses Kydex due to it retention power. Sheaths protect the user from injury as much as they protect the knife from damage or loss. Harris says, "Any knife on the belt can be hazardous. When you fall, if it's flopping around, then the tip gets pushed into body parts. Bladesmith Gypsy Wilburn warns, "Kydex is malleable at low heat, making it a drawback in desert regions such as the American southwest. Substitute with ABS plastic if you are making sheaths for use in Arizona, New Mexico or Nevada, or if you intend to send your sheath to a soldier serving in the Middle East."

References

• Photos: Kydex knife sheath examples
• Kyley Harris: Kydex knife sheath retention
• Gypsy Wilburn, artisan and industrial blacksmith, Carrollton, Ohio

Resources

• Meg Smith: Tutorial: Make a Kydex Knife Sheath