Hi Don. I plan on diving usually max at 150 ft. but want to be 
      able to settle on the bottom at 5 or 6 hundred without getting crushed. 
      The dive location will be restricted to areas that don't exceed 
      600. This will require some beefy stiffeners. 
      The saucer design was inspired by one of Jaques Cousteau subs. I 
      don't have a set of plans. 
      I have borrowed extensively from other's designs, adapting them as 
      necessary to fit my goals. There are quite a few saucer shaped hulls that 
      have been built. Some worked and some didn't. I used 3/8 inch steel tubs 
      made of AS516-70 steel because it's an accepted material with a long track 
      record. If I was starting from scratch I'd have used 1/2 inch.
      Although the shape is a little different, the systems are basically 
      the same as a K boat, which has a long track record of reliability. The 
      stiffener ribs are the biggest difference over a K boat. The work involved 
      is quite similar as well. I wanted to sit next to my passenger, which is 
      how I settled on the saucer shape. From my testing, it requires a little 
      more power to move with this shape, so I've made the fairings and ballast 
      tanks as sleek as possible to minimize that. I expect top speed to be 
      around 4 knots, but will seldom reach that. These little subs we're 
      building don't go very fast or stay down too long, because of the limited 
      battery power. 
      If you're actually going to build one, ask lots of questions, get the 
      books and stuff from the psubs site. Take the time to learn what's do-able 
      with out spending 3 1/2 million, and then have lots of fun. To me, the 
      design part was the most fun, and took the longest. I built full size 
      mock-ups of different shapes, and once I decided on a saucer, I built 
      scale models in steel to test different aspects. Very time consuming, but 
      well worth it.
      There's an archive section on the psubs site, and although it takes a 
      long time to read, most of your early questions will be answered there. 
      The guys here are all friendly, and very helpful, and we all like thinking 
      about how to solve problems so don't be shy about asking.
      I think one of the first things you need to decide is "what you want 
      your sub to do". Form follows function.
      That more than any thing else will determine what the design will be. 
      There are as many designs as there are guys doing it. 
      There are some basic skills to learn, like welding, electrical, 
      hydraulics, air, machining, etc. but you don't need to be an expert in any 
      of them, just a basic understanding. Most of the stuff we use is "off the 
      shelf" with a little modification. The K boat plans are a little old, and 
      all the guys have modified them to fit their needs, with the availability 
      of new products and tools to make the job of building a little easier. 
      More than any thing else, it's been a learning experience. You can 
      probably expect to spend a minimum of $20K for one, and the sky's the 
      limit if you want extras. That price is with you doing all the work. Add 
      on hiring professionals, and it can get pretty expensive. I know one guy 
      who hired out most of it, and he's near to $70K for just a basic K boat. 
       
      It's an expensive hobby and not much chance at making money on it 
      without being ABS certified. That cert alone can cost $150K. It all 
      depends on what you want to do with it, and how much you're willing to do 
      your self. I'm not trying to talk you out of it, because it's the most fun 
      I've ever had, but many guys get started and don't finish. Let's face it, 
      It's a complicated little machine, and not really very useful. 
      Perseverance is probably at the top of the list of things you'll 
      need. That, and lots of money. But let me repeat, it's a LOT of fun. 
      Anyway, welcome aboard, and do the homework. Frank 
      D.