I was asked how do I make my leather canteens. I start with 12 to 14 ounce leather ( usually a 1/2 side of cow leather), then cut out two exact pieces that match and have been designed to hold about 500 to 750 ML of water when done. I then use rubber cement on the edges to glue the two pieces together then make sewing holes a little less than 1/4 inch a part. Using artifical sinew, I sew by hand with a running stitch. When sewed, soak it in water for 4 to 6 hours, some of the vegetable tanning will leach out. Then I pack it as hard as I can with sand, whick forms the canteen. Let it completely dry, then dump the sand out and I use marbles to loosen any that sticks inside. I use bees wax that I have melted in a crock pot and soak the whole canteen in it till saturated. Then leave about a cup in and let it cool a little, swish it around to get a good covering inside and you have a waterproof leather canteen.