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Browsing the classifieds

Posted: Jan 23rd, '10, 17:12
by Major
I was looking through the boat classifieds as ushuall and found some interesting boats and features.

So as yall know by now that leads to questions.

The first thing i noticed was a 30' bertram moppie. I didnt even know it existed and see that its built on a 31 hull from what a couple ads said. I also saw a few that had a transom door Which was cool to see. It looks like the weight distribution is way off from a normal 31 with the long nose but it doesnt have a flybridge. With all that said i saw a 30' flybridge cruiser that said it was built on the 31 hull but it looked like a 28 with a different interior layout and engine hatches. Is there such and animal? Has anyone that yall know of converted a 30 moppie to a flybridge cruiser?

I also saw another boat that had an arrangement of the engin boxes somewhat like a 31 but only half of the engine was exposed. The other half was in the cabin. How do they get the engine to the mounts or off of them when they only have access to the front 1/3? Seems like sound in the cabin would be bad as well.

Another thing i noticed with a 30' blackwatch was they mounted the rudders on the back of the hull vs "inside" like the bertram. What i mean is with it mounted inboard of the transom (bertram) you have strength and the pivot point moves in a little further so why would someone mount them to the transom? I would also add that the shafts and props were moved back as well.

Would having more hull behind the props help thrust? It seems like that would help direct it. Ive thought about making somewhat of a tunnel before to try to focus the thrust from and to the prop. What effect do yall think that would have? I would love to find a scale model of a 31 and 28 bertram to test ideas on or even just to look at for that matter.

What would be the correct way to extend a hull if it was cut at the engine box area? I know its complicated but how would you figure out the balance and more importantly making it stay in one piece .

Posted: Jan 24th, '10, 10:02
by dougl33
The 30 is not built on the same hull as the 31. Its a Napier design that was made to replace the 31.

Posted: Jan 24th, '10, 10:28
by mike ohlstein
There are lots of boats that have the rudders out on the transom. Tearing one off won't sink the boat.......

Having more hull behind the props will help to keep the nose down, sort of like a giant trim tab.