One of the friends I've come to know through blogging is Marc. He first emailed me way back in September 2009 because we both happen to collect Action Man although he's a true vintage Action Man collector - hats off to him :). The friendship just grew from there although in truth, I never met him until yesterday. Marc and family paid a visit to my Toy Haven (some say "Toy Heaven") and we had a fantastic time sharing stories and I learnt quite a lot from this great yet humble man. Not only that, Marc packed lots of makan for us (yes! he cooks some mean peranakan dishes too) and also brought me a gift - this Bronze (metal) U.S. Navy Mark V Diving Helmet which is a beauty! I say, he should come by more often haha
Diving helmets are worn mainly by professional divers engaged in surface supplied diving, though many models can be adapted for use with scuba equipment. The helmet seals the whole of the diver's head from the water, allows the diver to see clearly underwater, provides the diver with breathing gas, protects the diver's head when doing heavy or dangerous work, and usually provides voice communications with the surface (and possibly other divers). (source: wiki)
If a helmeted diver becomes unconscious but is still breathing, the helmet will remain in place and continue to deliver breathing gas until the diver can be rescued. In contrast, the scuba regulator typically used by recreational divers must be held in the mouth, otherwise it can fall out of an unconscious diver's mouth and result in drowning (this does not apply to a full face mask which also continues to serve air if the diver is unconscious).
Historically, deep sea diving helmets (copper hats) ranged from the no bolt to two bolt to four bolt helmets; helmets with six, eight, or 12 bolts; and Two-Three, Twelve-Four, and Twelve-Six bolt helmets. Bolts being the method of securing the helmet to the diving suit.
A standard diving dress consists of a metallic (copper and brass or bronze) diving helmet, an airline or hose from a surface supplied diving air pump, a canvas diving suit, diving knife and weighted boots. An important part of the equipment is the lead weights, generally on the chest, back and shoes, to counteract the buoyancy of the helmet and diving suit. Weighted boots may use brass, iron or lead for soles. The uppers are often made of oiled leather or canvas.
The type of diving equipment is also known as hard-hat equipment or a "John Brown" rig, so-called after the British company that built many of the helmets. In the United States, it is sometimes known as a "Diver Dan" outfit, from the television show of the same name. It was commonly used for underwater civil engineering, commercial diving and naval diving.
One of the best known diving helmets in the world is the U.S. Navy Mark V. The helmet had a top view port to provide the diver with an upward view. The front view port, called the faceplate, was hinged. Like this, no tender could incidently drop a faceplate overboard ! On the commercial helmets they tested, the exhaust was at the rear of the helmet. This was a good spot: air bubbles would not block the divers' view.
The Mark V was used by the U.S. Navy from 1916 till 1984, when the fiber glass Mark XII that was introduced in 1979, finally took over permanently. The only visible difference between the MkV helmets made prior to 1918 and those made after is the exhaust handle. The eight point exhaust handle is found on hats produced during or prior to 1918. It was changed to a four point handle on divers' requests. It allowed the diver to more easily adjust the valve and determine its setting. (source: divingheritage.com/markvkern.htm)
The front viewport is called faceplate. It is the only one that can be opened. This way the diver can speak to the tender without removing the bonnet. The faceplate on the Mark V is hinged, which is quite unique for diving helmets. Practically all other helmets have a "screw in" faceplate. A wingnut on a pivoting stud extending from the bonnet is rounded and tapered on the "seating" end and fits precisely into the receiving cup of the two pronged fork on the faceplate. To prevent the wingnut from unscrewing completely a small circular "keeper" is swaged onto the end of the stud.
The inscription reads "U.S. Navy Diving Helmet Mark V Boston Mass No. Date"
And here's the bronze copper brass diving helmet taking pride of place in my display :)
It belongs right there with all my other collection in my "Under the Sea" theme. You can check out my earlier toy blog post HERE to see the entire display. Also gives you an idea of the size and scale
 |
| Click on the picture for a bigger and better view :) |
0 comments:
Post a Comment