I've made several knife sheaths and I have my own design for keeping the knife blade from cutting the stitching or lacing. I stiffen a half inch wide piece of 8 to 10 oz leather and then wet form it to the curvature of the knife sheath. It then gets stitched between the front and back sides of the knife sheath and burnished smooth. This protects the stitches from being cut and it works like a charm.
A new customer ordered this knife sheath for his boning knife. He did not like the sheath that came with the knife when he bought it. So I pulled out my materials and went to work. He requested black and I'm glad he did because it looks pretty sweet. When he stopped by to pick it up, he raved at how awesome it looked.
There are many, many styles of knives for which customers would like a knife sheath custom handmade. The difficulty here is that it helps to HAVE the knife so that a template can be created. Once the template is created then it is just a matter of determining the color and any design that the customer would like carved, stamped or sculpted on the sheath.
Knife sheaths are leather items that I enjoy making for customers and, soon, I will be including them in our website so that customers can view and order them.
Until next time, All the best.
Frank, the KC Leather Guy