I have two bows with antler tip overlays. I cut the tip of an antler off to the length I want, sand one side flat as a pancake, fill that side with CA glue, sand smooth and use CA glue to glue it the bow, two clamps per tip for a few hours. I have never had one break on me. My bows are generally 55# or more. I think the key is using the hard outside of the antler for the outside of the tip, while the porous inside is filled with glue and facing downward. The best part is you can always replace them with other material if they fail you.