1/600 Scale HMS Neptune 1909 12"/50 (30.5cm) MKXI Guns x5. These are highly detailed parts modelled from original plans from The National Maritime Museum, also using a wide range of reference photographs. These have been created for anyone wishing to build a 1/600 Scale HMS Neptune as launched. See My Shop for other sets covering different scales and time periods. (Note: The HMS Colossus set is subtly different)
- Accurate armour thickness and dimensions from original plans
- Each Turret (except for P & Q) are different, Turrets are placed A, PQ, PQ, X and finally Y on Sprue (from left to right).
- Hex Nuts, Rivets, Sighting Ports and Hatches
- Barrels are printed separately and can be angled as desired to a maximum of 15º
Developed to arm the "next generation" of dreadnoughts, this was a long-barrel 12" (30.5 cm) gun that used a larger propellant charge in order to achieve a higher muzzle velocity. Unfortunately, these new weapons proved inaccurate, as the heavier charge did not always fully combust before the shell left the muzzle. This resulted in unpredictable muzzle velocities and thus a varying range for the same elevation. Following one set of exercises, Lord Fisher recorded that the salvo shell patterns were spread over two or three acres (1 to 1.5 hectacres). The higher muzzle velocities achieved also resulted in these guns having a relatively short service life. There are some notes about barrel droop being an additional problem, but I have my reservations about the accuracy of those descriptions.
As a result of the failure of these guns, the British implemented two significant changes. First, older ships with 12"/45 (30.5 cm) Mark X guns
were modified so as to increase their maximum gun elevations. This allowed them to achieve longer ranges without increasing their muzzle velocities. Second, larger calibers were rushed into production for new ship construction, as their heavier projectiles would travel a longer distance at any given elevation for the same muzzle velocity. This meant that not only would they fire a heavier, more damaging projectile, but that they also would enjoy a longer liner life.
Some publications claim that these weapons were used on the Indefatigable class battlecruisers, but all British 12" (30.5 cm) battlecruisers actually used the older - and shorter - 12"/45 (30.5 cm) Mark X guns
The Marks XI, XI* and XII were interchangeable and had similar ballistic performance. The Mark XI was a Vickers design and resembled the Mark X except that the screwed collar was replaced by a breech ring screwed to the rear jacket. One of these guns used on HMS Vanguard had a Holmstrom breech mechanism while the others used the same "pure-couple" breech mechanism as the Mark X
. Mark XI* had a short B hoop overlapped by the jacket and the C hoop shrunk over the B tube and screwed onto the jacket. To counterbalance this, a D hoop was added over the jacket in front of the breech ring. As a result of these modifications, the XI* weighed a ton more than the Mark XI. The Mark XII was a similar design and the same weight as the Mark XI but differed from it by having more wire along the chase. The Mark XI gun breech mechanism was powered by a 3-cylinder hydraulic motor in place of the customary piston-rack assembly. Single guns with minor differences were also made to Elswick, Beardmore and Coventry Ordnance designs. Mark XI**, XI*** and XII* were proposed variations that were to have had alterations to the chamber slope for use at high elevations, but none of these were ordered. A total of 85 guns of all types were made.
Some experimental work for these guns was carried out with pre-rifled 12" (30.5 cm) projectiles fired at muzzle velocities exceeding 3,000 fps (914 mps) and work was begun on converting one gun to a super velocity 8.071 inch (20.5 mm) gun, known as the 8-inch (20.3 cm) subcaliber Mark II
. This was a continuation of the experimental work started with the 8-inch subcaliber Mark I
. The work was cancelled at the end of the war.
Some part cleanup will be necessary. The 3D printing process uses a waxy substance to support certain part features during the printing process. Although the parts are cleaned by Shapeways, some waxy residue may remain. It can be safely removed with water and a mild aqueous detergent like "Simple Green" using an old, soft toothbrush, Q-tips or pipe cleaners. During the printing process, liquid resin is cured by ultraviolet light. Microscopic bits of resin may remain uncured.
Let your parts sit in direct sunlight for a few hours to fully cure the resin.
Water-based acrylic paints meant for plastics is strongly recommended.
Other paints, especially enamels, may not cure on Frosted Detail 3D-printed plastics.
Use dedicated model sprue cutters to remove parts to minimise the risk of damage to parts.
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