Good Morning Guys!
I finally got to the torpedo doors and shutters today. Using the information Scott sent, I learned that Batfish had “Balao” type doors on the bow and “Valley” type on the stern. The AMP site includes a picture of a Gato bow from “Warship Pictorial 28 – Gato Type Flee Submarines” by Steve Wiper, which I have included below.
I started by drawing a polyline on the lower surface of the number 4 tube…
…Followed by another polyline on the upper surface.
I then lofted between the two polylines to create a solid.
It occurred to me at this point that if I did it this way there would be holes left in the middle from the existing limber holes, so I undid everything and mirrored the polylines to the other side.
I then diced and sliced the polylines and joined the 4 polylines to make 2, which I then lofted.
I did the numbers 5 and 6 tubes in the same manner.
I decided to make the numbers 1 and 2 shuttersand doors in the open position, so they were done differently. The design was based on another picture I found in the links Scott posted.
I started by extruding a circle 0.01” from the aft face (on the outside) of the tube.
I then copied the disk just created adjacent to it…
…And rotated the new disk 90 degrees to make the open door.
Next I put a hinge on the door by extruding a circle vertically where the two circles meet.
I then extruded a smaller circle through the first circle, to create an opening for a torpedo. (Note, this circle will be used again later to cut through the hull itself.)
After that I added a face on the inside of the open door by first extruding a circle…
…Then cutting notches in it. It’s not exactly like the picture but it gives the surface some texture.
At this point, I had to add the torpedoes, and rather than wing it, I decided to make a complete torpedo to scale, so I downloaded some plans of an Mark 14 torpedo, copied it into AutoCad and scaled it. I then used the plans to make a 1/144 scale torpedo, starting with the body. In the image below you can see the circles I drew to make the body…
…Which was made by lofting between the circles.
Next I added the fins (and control surfaces) by tracing the outline on one side with a polyline, extruding it 0.02”, and centering it on the body. A pivot for the control surface was created using an extruded circle. The whole thing was then mirrored to the other side…
…And rotate/copied 90 degrees. Note I also rounded the edges.
To do the propellers properly would take considerable time, so, at least for the time being, I decided to do a crude approximation. I modified a circle and an ellipse to create a polyline that I extruded 0.01” and centered on the hub.
Since there are two props, I copied the shape over for the second prop.
After a series of rotates and rotate/copies I had what is a decent propeller. Remember they are only 0.12” diameter. If I decide later to display a torpedo or two on my model, I can always change it, and perhaps even make them out of PE.
For the current purpose, I copied the torpedo to my Part 01 drawing. I then extruded the circle that I mentioned earlier, through the hull leaving the nose of the torpedo clearly visible through the door opening.
Of course, I copied it to the other side too.
Last, I sliced off the aft ends of the torpedoes and joined everything together.
The stern is next, but it will be more difficult because of the nature of the “Valley” design.