Heres a link to G5's sharpener Ive never used one but I've heard some of the guys in my local pro shop talk about and they say that it works pretty well.

http://www.cabelas.com/cabelas/en/templates/links/link.jsp?id=0026341416413a&type=product&cm Cat=search&returnPage=search-results1.jsp&QueryText=broadhead+sharpener&amp ;N=4887&Ntk=Products&Ntx=mode+matchall&amp ;Nty=1&Ntt=broadhead+sharpener&noImage=0