Quote Originally Posted by turpin View Post
What they all said. I always draw my thread (poly embroidery floss) through a lump of beeswax when sewing my sporrans. In the old days the cordwainers made special concoctions of beeswax, pitch,and god knows what else to bit and hold the leather and make the seams watertight.
Two comments on this...from a harness tinker's daughter:

1. Sewing by hand, which means drawing a length of thread thru any material, produces HEAT. When applied to leather, this will dry the leather around the hole. The closer the holes are, the transfer of dryness can be devastating to a seam-think breakaway factor. On the same note, waxed thread isn't infallable-if you must do a long seam, do it in short spurts-or your thread will become de-waxed very quickly.
2. Waterproofing is valid-but not necesarily to the seam, more the cord. IF the cord gets wet, and stretches, it will get weaker, and potentially cut the surrounding material. Impregnating the cord with wax will prevent this.