Minnkota has a couple of new products out. There is a newer motor rated 
  at 2-1/2 HP coupled with trim tabs and electric actuators. The site I 
  read said the dual motor set-up would run a standard pontoon boat at 5 
  knots.
  I too will be using the regular Weed Wedge 2 props for now but would like 
  to use three or four bladed props as an upgrade later on the two rear 
  thrusters. They have 3/16" thick stainless prop rings on them now, acting as 
  kelp guards and rudders. I think I could fiberglass a Kort nozzle shape onto 
  the SS rings so adding multi blade props could add more "push". My side 
  thrusters will need to keep the "Weed Choppers" as they have no guard 
  rings.
  I was thinking it might be possible to fabricate some props from FRP. 
  Balance would be an issue and longevity too as the FRP is soft making it wear 
  quickly. For sure you couldn't run into anything with them.
  Could it be possible to buy aluminum props without the hole and machine 
  the correct size hole for a Minnkota shaft ?
  Another thought is to fabricate a new replacement end section that 
  fits a Minnkota with a magnetic coupling so no pressure compensation would be 
  needed. Bolt it on in place of the factory end section.
  The overall diameter would need to be larger than the Minnkota housing to 
  accommodate the mag coupling but if the shaft was extended a few inches a 
  taper could be used to clear the area directly in front of the prop.
  I mentioned this to my machinist son-in-law and he said he would be glad 
  to make something if I could draw it up. ( maybe later )
  I know Minnkota spent a lot of expertise designing their props for the 
  motor but I wonder if having it designed for chopping weeds has reduced it's 
  thrust output.
  True, I don't know shit about props, but there may be room for 
  improvement here.
  I finished the drop weight/carriage yesterday, except for some tabs to 
  attach the lead bricks and a little finish polishing. It's freakin' heavy 
  already. It has 6 steel rollers rated at 1500 LBS. each and two smaller 
  rollers so the sub will "teeter" on the main rollers. Should make it easier to 
  move the sub around on the shop floor and will be used when loading/unloading 
  on the trailer. Once installed, the sub will be MOBILE !
  One step closer to Florida !!!
  Frank D.