you might want to try African Blackwood instead of ebony - it's also jet black usually, and doesn't split nearly as bad - they use it for clarinets. If you do use ebony, work it a little at a time, never let it get hot, and be sure the scales and tang are DEAD FLAT - if you have to squeeze the ebony to the tang with clamps, you WILL have a problem - ask me how I know!
Bill