The Mexican loop style knife sheath was very popular in the Southwest US during the late frontier era post 1875 or so. One reason is the large loop allowed it to be carried on the cartridge belts of the period. The inspiration for my pattern came from the original carried by Texas Ranger, Bill McDonald (1852-1918), which is pictured below.

I adapted the style to hang lower on the belt and to eliminate the center front seam. The McDonald original was made of one piece of leather just like Mexican Loop Holsters of the period.

For the slotted loop style my construction uses four pieces: The face, the welt, the back, and the loop/skirt. When making the arched face there is a fifth piece - the welt wedge, and if making the riveted loop, a sixth piece - the loop itself is needed.

I recommend using 7/8oz veg-tan. Heavier leather makes it difficult to form the loop around the body. If you have a very large knife (10" or larger blade) I would recommend making the riveted loop style out of 9/10oz for the body and skirt and 6/7oz for the loop itself.

This style sheath is actually quite easy to make and I will try to explain my procedures so even a newbie should be able to figure out how to to do it. If you have any questions contact me at chuck@wrtcleather.com
PLEASE READ THE ENTIRE TUTORIAL BEFORE MAKING THIS SHEATH
The main part of this tutorial will refer to making the simplest style, straight throat, slotted and smooth edge skirt.
I will add notes to explain the procedures for making the variant styles.

The face, back, and welt are based on the same pattern (except as noted for the arched throat in the Cales image) so there really are only two pattern pieces needed as pictured here.

To make a pattern for your knife adapt the above. I use manila file folders to make patterns with. First I lay the blade on a piece with the crossguard presses against one edge. Take a compass and spread the legs apart 3/8". Draw an outline with the compass all the way around your blade, making sure you maintain the 3/8" - i.e don't cant the compass as you move it.. As an alternative, draw around the blade with a pencil and then using a ruler mark an outline 3/8" around the blades actual outline. I often reshape the tip of the sheath a bit as sometimes the 3/8" outline ends too abruptly and just isn't graceful to my eye. Check again and again to make sure everything is fitting right and then use a knife and carefully cut your face pattern.

HINT #1: When transferring your pattern to leather, use a red roller tip pen if you are going to dye the item brown. If the item is to be dyed black then use a black roller tip. If you are putting a natural finish on your sheath use a soft lead pencil. After drawing the pattern onto the face side lightly dampen the area with a sponge and allow the color to return to almost normal. Use a sharp utility knife and cut your item out. When possible use a straight edge.

SECTION 1:
Cut your face piece first before laying out anything else. Smooth and even the two sides (I use a small 4" x 36" belt sander). Use your stitch groover and mark around all three edges. Around the top edge the groove appears as a border. If you're going to tool it, now is the time, although a simple impressed single or double straight border just inside your stitch line can be very nice. Simple yet elegant. To make it, dampen the face and use a pair of dividers to impress the lines.

VARIATION 1: Arched face at mouth. This entails more work, including an extra part than the straight cut mouth. If you want to give this a go make your pattern as shown. If the guard is more than 1/4" wide on each side of the blade I recommend not to use this style as proper fitting can be a nightmare.

SECTION 2:
Next I cut out my back piece using the face as a pattern. Make sure you lay the two pieces smooth side to smooth side and then draw the outline of the face piece onto your leather for the back. Again dampen your leather and when it's ready cut out the back piece. I carefully cut about 1/16" to 1/8" outside of the line. This leaves me a little room to work with when lining it up to the front.
SECTION 3:
Next I cut my welt out. I like to fit my sheaths to the blades and the welt is the most important part of that procedure. Normally I use a piece of leather that is approximately 3/4 the thickness of the blades spine, a dimension that works 99% of the time. I have several weights of leather on hand, but if you only have one weight on hand you can thin a thicker piece by sanding on the belt sander or by skiving with a knife. I skive and then smooth out any ripples with the sander. This can be done after the welt is glued to the back piece. Of course if it needs to be thicker (unusual) you can glue two pieces together and then skive/sand to fit.

To make the welt I lay my back piece on the leather for the welt and draw around it. Now lay your blade onto the uncut welt and draw an outline of it on the leather, making sure you maintain the 3/8"+ all the way around between the edge and the face outline.

IMPORTANT: If the blade has a belly, such as on some of the big Bowies, you will have to make the mouth of the welt as wide as the widest part of the blade. Trying to fit a 2" wide section of blade through a 1 1/2" gap just doesn't work!

Again dampen your leather and when it's ready to work as described above, cut the section out to the INSIDE of the blade's outline. This is where your blade will fit.

Now lay the blade on the flesh side of the back piece and draw an outline of the blade onto the back. Next contact cement the welt to the back making sure that the inside edge of the welt is up against the blades outline.

HINT #2: To make sure the welt follows the blades outline as closely as possible (with the same caveat as above regarding blade shape) I glue the spine side down and then fit the welt snug up against the edge and glue it down.

Before proceeding trim away the excess welt material.

SECTION 4:
My idea of a good fit is when you can turn a sheath upside down and the knife won't slide out, yet at the same time it should not hang up in the sheath when being drawn. This can be a painstaking process of trying and fitting until gotten right. To get a good fit of blade to sheath I do the following:

I skive/sand the side of the welt along the sharp edge of the blade and the false edge if there is one
until the welt is between 3/32" to 1/16'" thick depending on your blade.

(For those who folks who are at this point thinking I'm crazy, proof is in the pudding - I have done it this way for at least 25 years and have NEVER once had a blade cut through the welt. If you're not comfortable with this method then skip this step and go on to the next section.)

Work SLOWLY! To test the fit, RUBBER CEMENT the front and back together and use a couple of small clamps close to the mouth to keep it snug there. If the blade is too loose pull the front and back apart apart (the reason for rubber cement and not contact cement) and skive/sand some more. If the blade has a false edge or is double edged (the hardest to get a good fit) I also trim the welt along that edge. The object is to have the leather along the face and back contact as much of the blade as possible. This gives it the proper tension for gripping the blade properly. If the blade has a ricasso you of course have to leave the welt the correct thickness and the welt will then be tapered along it's length from tapered grip to point, in other words a distal taper. Once I get a good blade fit I trim the back and welt to match the front. You don't need to final trim the sides at this point as that will be done after sewing the front and back together. But you do need to trim not only the sides, but the mouth as well and this is easily done on the belt sander - just GO SLOW! If you take too much off, the blade won't fit all the way into the sheath. It can be fixed by pulling apart the front and back and carefully carving the welt away, but it's better not to. After sanding the mouth edges even, I take an edge tool and trim the fuzz off the inside edge of the mouth.

To continue this tutorial click here.
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