The following is taken from ‘A Handbook of Practical Shipbuilding: With a Glossary of Terms’ – Pub .. page 132
The Engine Hatch consists of an opening in each of the decks directly over the engine. This is enclosed by a light bulkhead carried around all four sides from the lower to the highest deck which may be the bridge deck. Here the opening is covered by means of an Engine Room Skylight which is made portable so that it can be lifted off by means of a crane if there is any repair work to be done to the engine. On the top of the skylight, small shutters (or covers) are fitted so that they will hinge up on end and give plenty of ventilation to the engine room. For additional lighting, when the covers are closed, they are fitted with glass ports, or windows.
In order to obtain access to the engine room, a door is cut in this enclosure and a ladder is carried from there down to the engine room floor. This door is usually on the upper deck in the bridge enclosure where it is customary for the engineering force to be located.
The Engine Room often has four cowl ventilators fitted, one in each corner of the Engine Hatch, standing above the skylight enough to have an unobstructed draft.1
Note: From this I think it should be clear over the engine. The addition of a skylight fitted with shutters and glass ports/windows will add greatly to the model. A ladder/stair from the hatch to the bridge. This needs to be carried over in the ship design.
The Boiler Hatch is another opening similar to the one over the engine in that it goes up to the weather deck and is enclosed on all four sides below that deck. Opening through the enclosure gives access to the boiler room by means of a ladder. The top of this hatch is covered with what is termed the “Fidley Hatch.” This is a square box-like arrangement standing a little above the deck, which allows the funnel to pass up through and is covered with a grating to give sufficient outlet for air from the Boiler Room.
The Fidley Hatch – An iron casing enclosing the foot of a funnel, above the smokehole, sometimes also the boiler hatchway. It is fitted with bar gratings, “fidley gratings,” and lids, which may be opened or closed according to the weather.2
The Boiler Room is fitted with two cowl ventilators, of larger diameter than those in the Engine Room. They are fitted in the two forward corners of the boiler hatch and stand above the Fidley Hatch to have a good draft. The cowl hood of all these ventilators is built separate from the ventilation trunk pipe (which is round in section) and rests on top of the trunk as a guide, so the cowl can revolve. On the outside of the cowl, below the throat and just above the trunk a gear rack is fitted to engage with a pinion gear wheel. (operated from Engine or Boiler Room). The ventilators in the Boiler Room are made larger in diameter as they are also used as elevator shafts. The Boiler Room has ash buckets which are used to raise and dump ashes over the side into the dump scows while in harbor, if the steamer is a coal burner.3
The Cargo Hatches are sufficiently large to allow ample room for handling the cargo in and out by means of the Cargo Booms.
This coaming is braced strongly with pocket plates to the deck and carries a small angle around the inside, set down from the top a few inches, as a landing for the Hatch Cover.
Cargo Hatch Covers for the design just described are generally of wood plank about 3 inches thick arranged in lengths and widths to completely cover the hatch opening. Over the Hatch Cover, on the weather deck, canvas tarpaulins are laid and secured tightly by carrying over the edge of the coaming and held against the coaming by means of Battens.
|This diagram shows how a ship is birthed. On the stern it is basically reversed.|
|At some point during this I realized that I would need Cowl Ventilators for the ship. These were used on all ships prior to forced ventilation. I looked around and wasn’t happy with what I found. Even if a website shows some there is little information on them .. or a photo large enough to see how they are made. That made me decide to design my own in Sketchup .. so I made a separate thread for that. – Cowl Ventilator|