During our period, cordwainers and cobblers often used “waxed ends” to stitch one piece of leather to another. They consist of a boar’s nose bristle carefully attached to drawn-out linen thread.
Waxed ends have some advantages over metal needles: they easily follow an awl's path made through the thickness of the leather; and they fit through small holes without catching (as often happens with the eye of a metal needle where the thread goes through it, making it relatively large). I also suspect that in period they were much cheaper than metal needles, as is true today.
To make a waxed end, I take 3-ply linen thread and unwind it for about two inches. Then I use a dull knife to scrape each of the three individual plies into fiber at different lengths (bottom, middle, and top of the drawn-out section). I then twist these back together and run them through coad, an especially sticky wax. This results in an extremely finely drawn, sticky length of fiber.
Next, I take a boar’s bristle and split it about half its length; this is not hard because most bristles split naturally and are already started. I run the bristle through a chunk of coad as well.
Now, the tricky part. Insert the thread between the split bristles and snug it against the crotch they form, with about half an inch protruding. Bend that against the lower bristle and then spin it counterclockwise while slowly winding the other thread down over it for its length. Once done, keep the bristle spinning while moving the thread back up over what was already laid down until reaching the split in the bristle.
Finally, twist one side of the split bristle and the main thread overhand for a couple of inches, then clamp the two bristle sides together and counter-twist them backwards. Hold them tightly and apply more coad.
See videos that demonstrate this in practice. Speaking of which, it takes some practice to make these, but it’s worth the time to figure it out and use them for stitching. Large quantities of boar bristles can be purchased on eBay for just a few dollars, so even though you most likely will use each just once, a batch will last a long time.
Last updated May 17, 2021.