Suitable sacrificial materials include polymers such as {HEAD ~ wax} and epoxies, metals such as {TAIL ~ aluminum}, and glass 
Suitable sacrificial materials include polymers such as { HEAD ~ wax } and epoxies , metals such as { TAIL ~ aluminum } , and glass
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH