Or do they?
Enter bolts. Free of grease and dirt, unused in their direct purpose.
Yet quite handy for yours truly, to be used as weights for mended warp threads (cause: a knot or a broken thread). And also to even out a tension in an individual thread, if yours truly was not careful winding the warp to the back beam.
Way handier than plastic film cans with change, where a cap holds the thread. I find them chewing on a thread, plus, I abhor a thought to use money as dead weight.
THE SILKY WEAVE 