Click on any of the thumbnails
below for a more detailed photo
KYDEX is one of
the new wonder plastics that is impervious to water, ultraviolet,
solvents, the elements and almost all alien death rays. It's a thermoform
or heat moldable sheet which makes it ideal for home made knife sheaths.
And since it's pretty tough to carry a bowie knife in your back pocket,
you are, in all likelihood, going to need a good sheath.
Here's a quick overview of a
pretty basic knife sheath. Modify as needed to fit your knife and design
considerations. Plan ahead and lay it out before you start to cut or form.
I'll cover the basics here, but every knife design is going to have it's
own requirements. Lay it out on paper first if you want to try out
different ideas.
You'll need to start off by
making two jigs to mold the front and back from some scrap wood that you
more than likely already have laying around. The jig to mold the
back simply has a step to form the lip and shoulder on the back of the
sheath. This step should be about 1/32" more than the thickness of
the bolster.
The most convenient source of
heat to soften the KYDEX comes from a heat gun. This will give you a lot
more control than trying to soften the sheet in an oven. I like the
smaller nozzle and the higher heat that the Ungar provides, but the
paint stripping heat gun from Black and Decker works fine. Check Ebay ;
you should be able to pick one up for 20 bucks.
I use cheat lines drawn with
a silver pencil to keep me oriented, and tape to keep the sheet from
moving on the form while molding. Move the heat gun back and forth
slowly until the KYDEX starts to soften and get rubbery. ( And, yes,
I did melt a spot on the carpet. Yike! Learn from this! )
When the KYDEX is soft, I use
a scrap piece of wood to force it into place to get a good square
lip on the back of the belt loop. Hold it for a minute of so until the
KYDEX cools and hardens
Use the same technique to
mold the shoulder that will sit against the bolster of the knife
Use the heat gun to soften
the top of the belt loop . The silver pencil lines tell me where the bend
should occur and where to concentrate the heat for softening. The scrap
piece of 1/4" plywood will provide a good sharp corner to bend the
belt loop around.
When the KYDEX is softened,
flip it over, using a scrap piece of wood inside the loop to help
hold it in shape until it cools.
To make the jig to mold the
front of the sheath, you'll need to make a wooden copy of the blade just a
hair larger than the blade itself. The KYDEX will be molded over this.
You'll also need to cut out a profile of the knife about 1/8" larger
than the blade, cut out of 1/4" scrap of plywood.
Tape again is used to keep
the sheet from shifting. The silver pencil lines will help align the
plywood cutout and show you where to concentrate the heat.
When the KYDEX is softened,
use the plywood cutout to force the sheet over the wooden copy of the
knife blade. Hold it here for a minute until the sheet hardens.
I use a few drops of super
glue to hold the front and back of the molded KYDEX sheet together
temporarily until I can get some rivets in . Notice the fancy clamping
system. Hey, it works.
Drill a few 1/8" holes
for the rivets.
Use the rivet set tool and
anvil ( both usually available with rivet sets at any leatherworking or
craft shop) to attach the rivets.
I use my bandsaw to cut off
all of the excess sheet and get the sheath into the final shape. A simple
rubber eraser will get rid of all of those silver pencil lines. Touch up
any rough edges with 180 grit sandpaper.
With the knife in the sheath,
I soften a small spot on the front and push the KYDEX tight against the
blade for a good, tight, custom fit. The knife will now feel like it just
"Clicks" into place.
Hope you like black. Yes,
KYDEX does come in other colors but the composition seems to be different
enough that it's not as freindly to work with.
Here's a drawing for a
slightly more advanced custom KYDEX sheath using the same techniques that
we just ran through. This design covers more of the knife and part
of the handle for a very secure carry. Since these are custom sheaths, every one you make
will be different depending on the knife.