03-12-2022, 03:53 AM
Left hand threaded fasteners have a notch cut in each corner of the hex shape so you can tell if the thread is "backward". Some industrial equipment has "backward" threads that are marked as such. If you want to save that fastener, dose it with WD and let it sit overnight, then tap it lightly to set up a vibration to get the fluid to seep into the threads.
