Don't know if this is what it is called. I need to tighten a couple of stag fixed blades. Never done it before. i assume that you tighten the brass nut in the pommel on the end of the tang. Is there a special tool for this? Can I substitute or make something to do it with without damage? Also, should I be preserving the leather washers on my vintage knives to keep them from shrinking? If so, with what? thanks for any advice. Mark