As {HEAD ~ the consumable part} 605 erodes over {TAIL ~ time}, the gap 601 decreases until it disappears entirely, and another gap 602 begins to form between the surface of the consumable part 607 and the go no go gauge 600 
erodes over
As { HEAD ~ the consumable part } 605 erodes over { TAIL ~ time } , the gap 601 decreases until it disappears entirely , and another gap 602 begins to form between the surface of the consumable part 607 and the go no go gauge 600
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH