So my last I-400 was only partly successful and had too many design flaws and after it burst on a dive test due to a massive air leak, I scrapped the boat and started over incorporating everything I learned and parts from the last boat. If you are building a sub with a ballast system, choose a boat with a wide deck and go through the top, if you do a dynamic diver and a boat with a thin deck, I recommend access through the bottom. Here is the new boats vacuformed ballast tank. I used the hull for the mold to make the maximum tank to fit in the hull. I also used two solenoids for liquids to vent the tank on top and she dives in 10 seconds. the last boat took about a minute. The major design flaw in the last boat was not having the ballast tank divided in four sections to prevent slosh. The slosh caused uncontrollable porposing and this tank has four chambers and the boat flies very smooth with no slosh.  The next new thing I did was a Plexiglas deck that is in 3 parts, so I only have to remove the center section for access to the batt. I used 1/8" rubber for the gasket and Vaseline to seal the center and silicone for the two sections that don't need regular access. I would recommend not painting the deck because you can see the leaks. On its first pool test dive it was sitting in 4' of water and I could see the water pouring in from the bad seal job for the ballast vents, even with a 1/4+ inch of water in the stern 1/3 it still rose to the surface.  A view of the two valves for venting and I used a Clippard solenoid to push the water back out. I also upgraded the push rods, so they have less flex and more throw. I did not take a pic, but this boat has a pressure relief valve in case of massive air leak. This boat has done about 12 tests dive and the last one I let it sit on the bottom for 45 minutes and when I flipped the switch for it to surface it did and no leaks. This is probably the best sub I have built with the fewest problems, and I can't wait to shoot Joe and yes, the guns shoot great. I will put more pics up as I take them.
I have added a little more detail, but I think this will be all that I add until I know it works in combat.
Which is more accurate? Or has better range? I'd imagine those bullets do more damage, I'm all-in with that.
They are about the same because of the close range that they are fired. You would need fins to keep them from tumbling and we are only aloud 3/4" long. Deryk made some torps for our 1/72 subs that would travel up to 18' in a straight line and could put a hole in you about 10' away.
They are illegal because they are too long. Big Gun is 3/4" long. Deryk has a post on these maybe on the 1/72 page. I pulled this from my Capitani. max.
IIRC the problem was the damage. They could penetrate balsa, but would plug their own hole. So you'd have a 3" long torpedo sticking 2.5" out of your hull, and no water coming in. Then another ship would come up alongside and bump the torpedo, tearing it out and opening a huge rip in the sides and instant sink. Not very fun.
