I have drilled out a hole in a piece of antler for one knife, and on others, with wood, or antler, I have marked the tang on the half slabs, and then used carving tools to cut the slot deep enough to seat the tang and close up the two halves. If I had a router bit, I would not hesitate to use it to remove wood for a tang today.
When epoxies cam on the scene, I didn't hesitate to glue the handles to the tang. The softer, larger celled, cores of antler are the weak part, and using the epoxy actually strengthens Antler handles. Wood( except very hard exotics from Africa I can't afford) slabs always can stand re-enforcing.
I, Now, always solder the hilt/guards, when used, to the blade. On my first knife, I left the brass hilt free- with walnut slabs for grips. Even tho the wood had been drying for years, a year later, the hilt was loose and rattled. If I am going to use wood for a grip, I prefer to use a leather or other wood spacer behind the hilt to protect the front end of the wood slabs. :thumbsup: