Quote:
Originally Posted by Whimsical
Have been seriously looking at what engines I am going to use in the barge.
The designer originally spec'd 30 HP Nannis when they weighed 165 Kg but they have become more obese and now wiegh 186 Kg. I am going to use 20 HP Lombardinis which weigh 125 Kg each, saving 120 Kg overall. the "Wilderness " can be built with either diesels under the aft berth or retractable outboards further aft of the next bulkhead. I noticed how much smaller the Lombardini is and realised that it will fit where the outboard would normally go. This is appealing as I am still considering a galley down and this would free up enough space to achieve that. I did a quick check and the lighter motor further aft has a 10% lower moment of inertia than the standard setup so that isn't a problem.
So now I am left pondering the pros and cons of motors under the berths or ones that are accessed from the aft steps.
Aft steps a lot easier to do routine checks and operate thru hulls but more dangerous in weather. They get the stink out of the accomodation and should be somewhat quieter. They also better isolate the wet stuff from the inside.
The more forward location of the lighter motors would reduce the moments even further but I can't decide if that is a pro or a con as it would increase the speed of longitudinal motion.
Any thoughts available from the more enlightened here?
Mike
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Hallo Mike
Is there no way in installing the engines midships like was done in the earlyer St Francis 43 and 44 ? they where build in on the inner side of the
hull very close to the centre of gravity. The
saildrive legs pointed straight down while the
engine bed that is provided can be sawn off to fit the angle of the
hull on the inside.
You accomplish many advantages here
1.You bring the weight to where it is best , close to the centre of gravity
2.Noise is away from the sleeping quarters
3.With a box build around it that can be removed it is very easy to
work on them
4. making turn with your engines will give your
boat the ability to turn on a dime.
The Lombardinis are only 500 mm wide , 488 to be exact so you would need 600 mm from the side of your hull to place them there and that includes the box around them.
The only question remains can you than walk around them going forward.
I always loved the solution that Angelo Lavranos made and the hull of the 44 where very slim.
p.s. Illbruck from Switserland has made a special
noise dampening foam exactly for these engines. ,They did that for us and it is called Iltec VB 40
They did a
noise study for our cat see attachement and this foam works wonders and weights almost nothing
Good luck
Gideon