Driving screws into super-hard woods
The next time you need to drive a screw into super-tough, exotic hardwoods such as ebony, lignum vitae, osage orange or any of the new, dense hardwoods from the world's tropical forests, try this little trick.
Before you get started, you'll first need to drill pilot holes of the appropriate sizes. Then, use a grinder or a metal file to file away half of the threads and shank (from the tip to the underside of the head) of a screw that's exactly the same size as the screws you plan to use.
Next, use this filed screw to "cut" precise threads into your wood by screwing it into the stock, then removing it and replacing it with a "complete" screw.
This approach will keep your screws from breaking off.