Notre Blog


Almost ready to plank your model ship? Not quite. Let’s finish off the discussion on framing. Before the wales and the planks can be attached, all of the frames need to be beveled correctly. This means that the outside edges of all the frames are angled to a greater or lesser extent to follow the run of the hull so as to provide a solid support for the strakes. In English you say! Alright -the bulkheads at mid ship will be square but beveled toward either the bow or stern in the direction of the bow or the stern and the amount of bevel will increase as you get closer to either end. This is done so that the planks will have as much bonding area with the bulkheads as possible. The angle of the bevel is usually found on the waterline drawing. It’s better to do a rough beveling job prior to attaching the bulkheads to the false keel so that you don’t loosen the entire hull framework during this process. Use a rasp or long piece of sand paper attached to a piece of wood. Once the bulkheads are attached to the keel frame, use some sandpaper to refine the angle.

Speaking about the waterline, make sue that you have drawn the load water line on both the false keel and the bulkhead. The waterline at which the loaded ship floats is usually not the same as the design waterline because ships tend to be trimmed astern and thus the waterline is not parallel to the keel.

Start with the wales prior to any planking. The wales are a series of heavy planks the width of which may be the same as the hull planking but with greater thickness so that they protrude beyond the planking. The tops and bottoms are usually slightly rounded off and you can find more that one on a ship. The wales are used to provide extra support to the frame. When fitting the wales work alternatively from starboard to port side and make sure that they follow the markings on the frame edge and have a regular and smooth run without flat spots and sudden bends. Now we get into some fine details when building 16th and 17th Century ships versus 18th and 19th Century ships. The former had wales extending 3 to 4″ beyond the planking and the later 2 to 3 inches.

For the rest of this series of articles, I’ll talk in terms of an 18th Century ship that measured 155 feet in length. The scale will be 1:48. So the actual length of the model is 38.6″. In the example above concerning the wale protrusion, you would want the wale to extend 1.5mm beyond the planking.

Now that we are talking about scale let’s look at the length and width of the boards used in an18th Century ship. The width was between 11inches and 14 inches which extrapolates to 7mm as the ideal scale width. The length of the boards were between 20 ft and 24 feet or in scale about 5 ½ » or 140mm.

The most common type of planking is carvel where the individual boards or strakes are butt-joined to each other. For modeling purposes, the most practical method of planking is to attach it in two layers. The first base layer will be a thicker piece of wood that will provide structure and shape to the hull (you can consider this your practice planking layer). The second layer is a veneer that is your finishing layer. For the base layer you do not need to worry about the scale length. To provide extra rigidity, you can glue pieces of wood in between the bulkheads on the inside of the hull. There are strong curves at both the bow and stern ends. You want to pre-form the planks the best you can. There are a number of methods you can use but they all involve water and a jig. Soak your plank in warm water for ten to fifteen minutes. This is just enough time to make the cells of the wood pliable without breaking down the structure of the cell. Place the wet wood in a jig that simulates the shape you need and let dry. For very severe bends or extremely thick pieces of wood, you may want to step through this process a few times changing the angles of the jig as you go along.

And now for a few words on plank bending tools. The simplest jig is one that you make out of scrap plywood and nails. Form the nails into a crescent shape and wrap with tape to prevent rust spots on your plank. There are commercially available tools that do the same thing but are adjustable so you can change your angles. Another method is to use an electric plank bender. This is an excellent tool for thick pieces of wood. You will only require to process the plank once and it will hold it’s shape. Some builders wet their wood and hold it over a candle flame as they bend the wood. Others make a steam tube out of plumbing PVC pipe that is capped on both ends (one end being removable). No matter what method you use, remember that if you use wood glue to adhere the plank to the frame, you need to let the wood thoroughly dry because wood glue is water soluble (the key to success when gluing two pieces of wood together). At alternative is to use contact cement. The advantage of this glue is that the wood can be applied while damp and in its’ most pliable state.

The next useful step is to measure the actual run of the planks on the hull. To do this, divide up the hull at the mid-ship frame into divisions the same size as the width of the planks. You now count the number of planks, and divide each bulkhead in turn into the same number of divisions. If the points thus marked are joined with a thin bevel batton, you will obtain the exact run of the strakes. At the ends, the planks should never be narrower than 3.5mm or wider than 10.5mm for a 7mm wide plank.

Start applying the planks one by one, first the starboard side and then the port side. There are a few methods you can use to clamp the boards to the frames while the glue dries. There are clamps with lips that either screw into or attach to the frame and hold the board in place. Because you are applying the inner layer, you can also use brass nails to fasten the board to the frames. The nail heads will sand off so you can leave them in place once the glue has cured. But the best technique is to apply a spot of CA glue (fast dry) to one end of the board for positioning, then apply wood glue to the rest of the board, turn the TV onto your favourite game and while enjoying yourself, hold the board in place with your fingers for about 20 minutes. At the next commercial break, start another plank on the opposite side of the hull. I estimate in a 3 hour game, you should be able to apply 8 boards.

With the first layer now planked wood filler is applied over the entire hull, and subsequently sanded off. This is repeated until every crack, groove, dent and bulge has entirely disappeared. Make sue that the hull is symmetrical on both the starboard and port side and check the run from bow to stern.

It’s now time for applying the finishing veneer layer. For our sample hull we will be applying the veneer in about 5 section runs. The usual pattern of the shift of butts are either three plank shifts or four plank shifts. Just remember that the butts always coincide with the frames. You may want to apply or simulate nails or spikes and you also may want to simulate tar lines in between the strakes. Apply the veneer using the same methods you used to apply the first layer of planking.

Once the hull is planked it is the ideal time to apply a finish. For unpainted hulls, you should use a semi gloss varnish that has been diluted 30% for the first two coats then full strength for the final coat. Lightly sand in between applications.

If you are going to paint the hull and before the model ship’s hull can be fitted to a display stand, the underwater hull has to be completed. First mark the waterline on the hull. Once again there are commercially available tools but a block of wood with a pencil attached at the correct height for the ship’s waterline works great. Just carefully walk the piece of wood around the stationary hull. Below the waterline the hull was usually painted with wood coal tar which coloured it a dark brown or almost black. Sulphur was often added to the tar to offer protection against worm attack. This resulted in a yellowish grey colour. The alternative was to paint the underwater hull with a white lead paint, which produced a dirty white finish.

From the middle of the 18th Century, it became common to sheath the underwater hull in copper sheeting. For our purpose, we’ll assume that our ship was built after 1850 and was British so it would have had copper sheathing. The size of the sheet would have been 48″ x 15″ scaled to 25.4mm x 8 mm with a thickness of.004″ In order to simulate the nail fasteners, you can either purchase preformed pieces or use copper strips cut to size and a 7/16″ pounce wheel to simulate the nail heads The copper sheets usually overlapped from bow to stern and from top to bottom of the hull. So start at the bottom of the stern and work forward and upward. Contact cement is good for adhering the plates to the hull. After installation is complete, clean them and apply a coat of clear protective lacquer

Our next topic will be on planking the deck.

Source by Wray Hodgson

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