A bit of HDR trickery

[artemis]

And a number of noted small craft designers - the Atkins, Bill & John, to name a couple - occasionally had the propeller shaft at an angle, in the horizontal plane, to the keel. This was to compensate for "crabbing" or "walking" when going astern. But they mounted the engine in line with the prop shaft.

[steamboatjack]

Daniel,
No offence taken! The drive is by tooth belt, it was originally in line but above the prop shaft, I off set it to make a bit more room in a rather narrow boat.
Regards
Jack

[dhic001]

Thanks for that Jack. Interesting method of drive, I wonder how long the belt will survive with the loading. We did have one boat here with that arrangment, but the vessel was soon modified for other reasons which allowed the drive arrangement to be changed to be standard shaft drive. How long the drive belt would have lasted was always up for debate.
Daniel

[steamboatjack]

If you follow the design criteria of the belt manufacturer you will have no problem, I have used two in twelve years but only because I needed a longer one for the offset. As they come in various widths they can cover a range of powers, The only point against is that to keep the belt size sensible the pulleys need to be as big a diameter as you can get away with, which in my case means the prop shaft pulley is near the bilge and will flick up water if you are tardy with the de watering.
The engine and propshafts are parallel of course. By the way I would never use universals or any automotive derived parts on a steam boat (although many do successfully), The first Elliott Bay triple is going to use an industrial double coupling "Sentaflex-A" The shafts will be properly aligned, the coupling is to allow for hull flex etc.
Regards
Jack

[artemis]

Is this off topic ?

[87gn@tahoe]

I thought steamboats ARE the topic?