In the past weeks I worked on the turrets, barbettes, funnels and the foreward bridge.
The barbettes were turned from perspex. I just saw a circular hole with a compass saw to clamp it in the lathe and turned it round and in form.
The funnels, the coning tower and the masters of the turrets were made largely in the same way. I cut out two pieces of 1 mm sheet styrene in the outline of the funnel, turret etc. minus 0,3 mm all around. Then two spacers were cut alo from 1 mm sheet styrene and glued between the two outlines. This frame was then enveloped with 0,3 mm sheet styrene.
The ceiling of the turrets were made in a sandwich-type construction from three sheets of 1 mm sheet styrene
From the master of the turret a form was cast in silicone rubber in which the differnt turrets were cast in resin.
For the funnels I needed two of the enveloped frames each. Because the upper tube should stay open the 0,3 mm sheet styrene cover reaches app. 1 cm over the upper frame. When the inside of the funnel is painted black this frame can’t be seen. The cover of the junction between the thin upper and wider lower part of the funnel is made from perspex which was cut out, sanded to shape and the holes for the pipes were drilled in.
For the upper part of the coning tower the frames were cut as rings and get a 0,3 mm cover on the out and the inside, the inside cover reaching app. 5 mm higher than that on the outside. The space between these two „walls“ was than filled with putty so it gets a sloping upper edge.
The platforms for the forward bridge were cut from 0,8 mm aluminium and arranged round an 18 mm PVC tube as the main shaft. The compass-, the cardhouse and the anteroom of the shaft were photo-etched parts.
Some words about photo-etchingPhoto-etching is one of the easiest way to get high-quality components. Compared to other usful tools like a lathe or an electronic milling machine the necessary equipment is quite cheap.
First you need an ink-jet printer (I use a HP Deskjet D 1560) and a good graphics software (I use Paint Shop Pro but freeware programs like GIMP or (if one is used to vector-based programs) Incscape will do also.
The other thing you need is an exposure unit to get the graphic on the sheets. I use a Isel UV-Belichtungsgerät Typ 1 which I got for roudabout 100,00 € on ebay, but there are several DIY guides on the net and a facial tannier or even a simple florescent shop light with UV tubes will work also (but are less comfortable)
The last thing you need is the etching tank. You can purchase one, f.e. here:
http://www.saemann.de or build one yourself (one DIY instruction is here:
http://www.youritronics.com/diy-etching ... nd-heater/). The tank is simply a perspex or glass cell with an aqarium heater, an aquarium pump and a surgical tube with holes to produce bubbles.
And of corse you need transparency film for inkjet printers, photo resist coated metal sheets (brass or nickel silver) and chemicals for developing and etching.
First you have to design the things you want to be etched with your graphics software. Always bear in mind that the acid will etch the metal from both sides, so you need two layouts for it (one for the front and one for the back). The most simple way is to just mirror the design, which will result in a straight piece that will look the same from both sides. That may be helpful for small or difficult to saw out pieces (f.e. rails) but means giving away the real potential of photo etching. With a little work you can create complete explosion drawings of pieces which you can simply fold to shape.
Your front and back designs should than be arranged to a plate (don’t create plates of more than 10 X 10 cm as the etching process can be quite different in differnt parts of the plate resulting in parts vanishing while other parts are not completely etched through), the back side being the mirror of the front side. These plates (front and back side) are now printed on transperancy film. The prints have to be placed on another and adjusted exactly, than glued together with a stripe of sheet styrene between them (the thickness depending on the thickness of the needed metal sheets, f.e. if you want to etch 0,2 mm sheets you use 0,3 mm sheet styrene) to a sort of envelope.
In this envelope you place the metal sheet, than put the whole thing in the exposure unit and expose it (the exposure-time have to be testet the first time by a bracketed series). Don’t forget to expose both sides.
The exposed sheets are then put in the devoloper (for better results and a faster process the developer has to be heated to app 40 degrees Celsius) and when completly developed under clear water to stop the process. The sheet should now show on each side the intended layout.
Then the sheet is put in the acid (I use Na2S2O8 but FeCl3 will work also but slower). The way to good results is to etch as fast as possible to minimize the time the acid has to etch on the rim of the pieces that should stand off (the so called undercut). Neatly observe the process to get the plate out when the pieces are completly etched and before the whole thing vanishes in the acid. Then again the Plate has to be put under clear water to stop the process and your self-etched pieces are ready to use.
As you see photo etching is no dark art and with a little practise on your graphics software you will get far better and more accurate (esp. when you have pieces you need a lot of) results than with fretsaw or cutter-knive.
To be continued ....
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I love mid-to-late 19th century French Naval Architecture what with the extreme tumblehome and pronounced ram bows... They simply looked powerful and menacing. 
