Good luck with that. Unless you have access to a cnc machine, you'll end up with something that isn't concentric and / or loose and won't stay tight. Furthermore, the bolts will only contact a half circle and might bend or split the chainring. Anyways, you can get NOS 151 bcd Campy track chainrings for about the same money as modern Campy, Shimano, Sugino from places like Velomine >>> http://cgi.ebay.com/ws/eBayISAPI.dll...=263602_263622