I'm trying to replace a broken shaft in my sheet metal extrusion machine, but I've run into some machine screws that just will not budge. They're 3/16th, Allen type, steel screws, mounted in an aluminum block. They have a patina of rust on them, and I already broke a new bit trying to bust the first one loose. I sprayed them all with WD-40, and gave it an hour or two to soak in, but still no go. Anyone know of a better lubricating product, or some trick I can use to get these suckers to turn?
