In 1755, having risen to be a mate, Cook joined the Royal Navy, and after four years' service was, on the recommendation of Sir Hugh Palliser, his commander, appointed master successively of the sloop Grampus, of the Garland and of the Solebay, in the last of which he served in the St. Lawrence.
Tap Bolt vs Cap Screw. What is the difference between a tap bolt and a cap screw? A tap bolt is (typically) a fully threaded hex bolt, while a cap screw is (typically) a hex head bolt that will be installed by turning the head of the bolt (screw) instead of tightening it with a nut.
Step 1: Determine if the thread is. T tapered or S straight (parallel). Use a caliper to measure the nominal male or female. thread crest-to-crest diameter on the first, fourth, and last full threads (Fig . 1) . T If the diameters increase for a male end or. decrease for a female end, the thread is tapered . S If all the diameters are the same, the thread is. straight (parallel) .