thanks, Mark. Thank you for saying that, that was what I was going to try next, however I didn't think about the center line on the lip, thats so obvious, yet genius. My concern (probably unnecessary) was chipping the edges of the slot in the shaping process, do you see that as an issue? if you don't mind, another question; on a 1.5-2" flat sided square bill, how deep do you cut the lip slot? thanks.