dirtdoc1
Senior Member
- Joined
- Apr 12, 2016
- Messages
- 472
- Location
- United States
- Vessel Name
- Ann-Elyse II
- Vessel Make
- North Pacific 45
Hey Jim,
I was on my way to become your neighbor but got side tracked around Oregon. Went up the Columbia river for a couple of days and ended up staying in Portland. Both my daughters live there.
Anyways - roll reduction. I estimate better than 90% at worst case, up to 100% best case. You can set the sensitivity to an infinite amount of settings. Well actually, to 100 settings from 0-100% in 1% increments. I found 80% to be the most comfortable. You would think that 100% would be the most comfortable but once above 80% the fins start to work pretty hard and I could feel a slight shutter on a big wave when the fins would slam all the way over trying to maintain no roll. It was a very slight shutter and it took me a while to notice it.
I think the reason for the fins to work as hard as they do (occasionally) is due to the speed of the boat. The faster the boat goes, the better they work. Also my boat is starting to get on the small side for this type of system. Since I'm always travelling below 10 knots we had to go to a larger fin. We also had to strengthen the hull. Dave Rassmusen (I always like to drop his name because he's great) built these massive maybe 2.5 to 3' square by about 6" thick wood backing plates made out of multiple blocks of wood that he glued together and glassed in to the hull where the fins go through.
In an effort to better explain what I was noticing. When a big wave would sneak up on us the fins would sometimes - not always, slam all the way over to try to keep the boat at zero roll. When this happened I could feel a very slight shutter. If I reduced the sensitivity of the fins this would go away with no apparent increase in roll. So now I keep them at about 80% sensitivity seems to be the sweet spot for my boat. The interesting thing is at 80% I don't notice any roll. Keep in mind that I have about 6 days of experience with the system.
