Tell, I would not use TB3 or the other wood glues like it, they can shrink as they dry and may take a couple applications to get what you want. I use either super glue and sawdust or epoxy and sawdust. Sears used to sell a filled epoxy that was great in these applications, but it was dark gray and looked bad on a bow. If the spot on the bow is going to bend, I use epoxy and sawdust. If it isn't going to bend I normally use super glue and sawdust. However, the color is not going to match perfectly, even if you use sawdust for the bow you're fixing. Not sure why that is.
Good luck,
George