I just found a neat old Yew longbow in an antique shop. It's in great shape except that one of the horn bow tips is missing. I have a nice cow horn that will match, but need a little guidance as to how to proceed. Your assistance is much appreciated! Richard
Richard, the process and tools used depends on how they're shaped and installed. Pictures would help. Is the yew's gluing surface flattened, or conical shaped?
To drill the cone shaped hole, you can grind a spade bit to the shape you need. I made this one from a 5/8" bit for a big beefy heavy draw weight bow I made, but you can either stop short with it, or use a smaller bit for smaller bow tips. I made one from a 1/2" bit as well.
Grind the cutting edge at a slight angle so that only the leading edge contacts the horn while drilling. You can see this in the picture in my last post. See the shadow on the edge on the right side, but not on the left? No need to sharpen it any more than that. It'll go through horn like butter.
You can shape the bit closer to your bow's existing angle and/or trace the shape of the bit onto the bow tip to help with shaping so they pair up well.