Nautical Research Journal
I suspect that cowl ventilators must be the bane of their existence for both paper model designers and builders. T e overwhelming majority of cowl ventilators have bowl shaped cowls. T ere are a very few that function by taking advantage of the venturi eff ect and have conical cowls with small holes at the rear, but these are very exceptional. T e design and construction challenge is to produce a bowl shape using paper, which inherently is fl at. Designers have tried several diff erent approaches: a series of wedge- shaped rings that stack to make the bowl; petal shapes that curve into a bowl; or a shaſt extended at the upper rear to form the lower part of the bowl and a second element that curves into a modifi ed cone (oſt en simply settling for a cone and trying to fi nesse the issue).
20. T e two ship’s boats completed.
Mörck’s parts, modifi ed as necessary. First came the skylights. T ese needed to be white, so I made them from the parts supplied but assembled inside out and used dark blue-grey paper that matched the deck lights I made previously to replicate the glazing. My spare parts collection was the source for the two canvas-covered ‘heads’ which, despite their name, are right aſt .
T e anchor bitts, two sizes of bollards, and the fairleads all were Mörck’s parts. T e bitts and bollards were not diffi cult to make but this was quite a monotonous project—rolling a dozen or so tiny paper tubes and capping them with punched discs of the appropriate size. T e fairleads, however, were very small and with rather thin sections, so I added a tiny amount of cyanoacrylate glue to each one as I completed it for strength. T is stiff ened them and allowed me to use a small fi le for fi nal shaping. T ey were painted very dark gray before installation. Even using this technique, my wastage rate was quite high—I had to attempt eleven fairleads in order to end up with the six I needed for the model. (Figure 15)
Mörck supplies this last type of cowl ventilator, so I decided I needed to do what I could to end up with a respectable approximation to a bowl-shaped cowl. I started by rolling the shaſt itself in the conventional way. Aſt er cutting out the cowl part, I used a simple domed hard wood tool to simultaneously roll the cowl part into a conical shape and dish the paper as I rolled it by pressing it onto a semi-resilient pad (a folded paper towel works well, as does the palm of my hand). I found that if I persisted with this process the paper formed itself into quite a reasonable approximation to a bowl. (Figure 16)
Aſt er butt joining the small ends of the piece, I let it dry thoroughly and then glued it to the shaſt . Again, the assembly was allowed to dry thoroughly, aſt er which I carefully used the dome tool to press the assembly onto the semi-resilient pad. T e end result was quite satisfactory. T e inside of the cowl I painted red with watercolor paint. I set pins in their position on the deck to increase their stability. (Figure 17)
I next fi nished working on the details on the turret top. I fi rst carefully removed the ‘rifl e proof ’ palisade around the turret top because I had learned these were not fi tted until later. I next made up and fi tted the distinctive awning stanchions. I marked out the
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