How to string your bead loom. To string a loom, attach your nymo thread to one of the small nails at the end of the loom. Run the thread over the metal bars (located on both ends of the loom) and wrap it around one of the small nails on the other end of your loom.ize 8 seed beads are normally to heavy to be used on a loom. The end result would be beadwork that sags in the middle. Every other slow on the metal bar was skipped to accomodate size 8 seed beads. You will not need to do this with seed beads sizes 10-15 that are the correct size beads to use on a bead loom.