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.
Bolts grip and distribute differently, depending on variables such as thread pitch, head size and, of course, whether the bolt is fully or partially threaded. To ensure proper grip and resistance to breakage, itâs important to use a bolt that meets the original engineering specs. Full vs. Partial Threads. To understand how these bolts grip differently, itâs important to understand the basic differences in their designs. Fully Threaded Metric Bolts: These bolts have threads running the full length of the bolt, from the underside of the head to the tip.
The picture below has both threads. Itâs hard to see the difference, but there is a difference. The taper of the threads is what actually distinguishes pipe from compression fittings. On bottom of the fitting in the picture is a male pipe thread; on top is a male compression thread with nut. Pipe threads connect the fitting to another solid component, like a filter housing or a rigid metal pipe.