I recently got a 26 Tiger Cat that is phenomenal heading off shore but is challenging with a stern quartering sea, on the way in.
My limited experience has shown me that trimming the port motor up on a port quartering stern sea on the way home, is less likely to dig the starboard bow and jerk the boat to the point of fear of rolling it over.
What I don’t understand is why. It would seem that I should raise/trim the starboard motor and raise the starboard bow. It appears that by raising/trimming the port motor pushes the starboard sponsion down and the buoyancy effect is increased??? on the starboard side???
I don’t know and I’m asking those out there that have driven a power catamaran and can help me understand the best way to handle this quirk.
every cat I have ever been on had a hard time with anything close to a following sea. It felt like you were an egg on a moving frying pan. sometimes enough speed would control the squishy movements, or sometimes made it worse
I slowly picked up speed after scaring the stool out of me and my boy the last time coming in. He had a grip on the side grab rail(Now I know why it’s there) and his eye on me. I tried lifting the port motor and kept my hand on the throttles to the sound. It will keep you busy.
I respect boats and would rather not be fearful of losing control. Trying to find others experience and thoughts.
Not sure if this is what you’re asking, but think of the motors like trim tabs on a single boat rather than thinking of the boat like two hulls. If you tilt the starboard motor up, it will push down on that corner and lift the corner diagonal (port bow). So, if you want to raise one side of the bow, trim the other motor up slightly.
I think the issue with following seas also has to do with bow steer from the shape of the bow (not quite plumb, but usually closer than most mono hulls). Obviously the best option is to avoid the quartering seas if you can, otherwise it sounds like you’re on the right track by keeping the bow trimmed up some.
Others with more experience may be able to give better advice. I only ran a cat boat for a couple seasons.
BRYSON IS CORRECT, IT WORKS LIKE TRIM TABS.
I HAVE RUN CATS FOR YEARS, AND WHEN I FIND MYSELF IS THOSE SEA CONDITIONS, I SIMPLY CHANGE COURSE, AND TACK LIKE A SAILBOAT CHASING THE WIND.
IT TAKES AN EXTRA 20 MINUTES TO GET HOME, BUT ITS MUCH SAFER.
The sea conditions were no more than 1.5s but only about a foot apart. I would have ate it up going home in a v hull.
If the trimming the motors acts as a trim tab… in a v hull with a port stern quartering sea as above…I would slightly trim tab down on the port side and trim the motor up…on a v hull…to make speed without stuffing the bow.
On the catamaran, which has trim tabs(both up) trimming the port motor up with a port stern quartering sea “RAISES” the starboard bow …that is what I don’t understand. The port bow should lift if the motor is being trimmed up on the port side…this is where I’m having trouble understanding.
Chris…I did run more parallel to the waves and understand your point. Just want to know why it seems that trimming the motors has the opposite effect on a catamaran as far as bow rise. I noticed it in the river when I had more weight on the starboard side and trimming the starboard motor up made the list worse…corrected by port motor trim up. That is what I want to understand how this works.
BRYSON IS CORRECT, IT WORKS LIKE TRIM TABS.
I HAVE RUN CATS FOR YEARS, AND WHEN I FIND MYSELF IS THOSE SEA CONDITIONS, I SIMPLY CHANGE COURSE, AND TACK LIKE A SAILBOAT CHASING THE WIND.
IT TAKES AN EXTRA 20 MINUTES TO GET HOME, BUT ITS MUCH SAFER.
What Bryson and Chris said… and don’t over steer/ steer too much. stay dry from the “sneeze”. With a monohull you steer and throttle … with a cat you judge wave pattern/direction.
I’m impressed Patagonia Man. I’ll post up my reasoning for buying an offshore boat at 65. I always wanted a cat after riding on the first Benchmark Cat at the Miami Boat show …many years ago.
I’m honored by such a benign post. You have a spot on “my new rig” anytime you want. You and your bud…Bonzo( the cat litter bucket mogul)
Maybe he’ll take the hex off if he’s fushn…and show us how to take bait off a Sabiki with a de-hooker. That should be entertaining…
I think your cat might need a new litter box! I always wanted a cat when I was younger. Invite me for a ride sometime!
I needed a new pair of shorts after digging that bow. You’ll be impressed by the ride into a bow sea…any direction. The whip roll will catch you and it is impressive. I fished the banks by myself and tied a rope on my azz…only do that when sleeping on the boat by myself due to sleepwalking. It will throw you out if you not paying attention. After the smooth ride out…you can kick me in the nuts after years of getting my teeth knocked out on a v-hull. I can put up with bad character for drifting(side to) for the ride out…
The run in is another thing. I make phenominal speed going out…the ride in is the problem that others have commented on. We be old but not to old to learn a new trick. I’ll figure this out.
You have a spot as well if you can handle a dude in Patagonia atire and a guy that has a cat litter bucket fettish. It will be something different for sure.
The boat weighs 5000# and has 2 150 Suzuki 150 4 stokes and made a mile to the gallon with 2 100 gal tanks. Same as with 2 strokes that are on old posts( 1998 hull) so I looks for foam being saturated…can’t find any unless it is cored somewhere(open to anyone who is alive that knows).
Checked the depth of the anti-ventilation plate and it was buried. At that time, the motors were on the lowest hole setting…upper and lower bolts( no open channel on the bottom like Yamahas{stronger design but a PIA???} The last good tree limb I have left on my yard after the last herd a cane, required a 4x4 as backup and motors were raised 2 holes…probably should have gone 3… we’ll see.
The hardest part was removing the inspection plate covers in the stern pods…some kind of sealent that required some prying…idiot that did it. Presently about an inch above the bottom of the transoms…we’ll see.
THe reason for the lengthy post is, by raising the motors, will I lose any noticeable abilty to trim the motors that is obviously required to control the boat??? We’ll see.
As always, I wouldn’t axe on a public forum if I was talking to myself.
And Skinny, glad to see you posting and I know you gots a cat…and you never been short on opinion.
Also swapped the drives to have the counter rotator on the starboard side so the props turn toward each othe and give more combined thrust.
Stern lift is mentioned as a positive ie. changing to 4 blade props. Presently running 3x15 1/2x 17 with rpm of 6k at full load so it is propped correctly…FOR THE LOWEST motor setting. I would imagine the rpms will increase after raising the motors 2 notches…we’ll see.
I need this boat to make at least 1.5 mpgs or better to make the amazing ride worthwile. We’ll see.
The boat weighs 5000# and has 2 150 Suzuki 150 4 stokes and made a mile to the gallon with 2 100 gal tanks. Same as with 2 strokes that are on old posts( 1998 hull) so I looks for foam being saturated…can’t find any unless it is cored somewhere(open to anyone who is alive that knows).
Checked the depth of the anti-ventilation plate and it was buried. At that time, the motors were on the lowest hole setting…upper and lower bolts( no open channel on the bottom like Yamahas{stronger design but a PIA???} The last good tree limb I have left on my yard after the last herd a cane, required a 4x4 as backup and motors were raised 2 holes…probably should have gone 3… we’ll see.
The hardest part was removing the inspection plate covers in the stern pods…some kind of sealent that required some prying…idiot that did it. Presently about an inch above the bottom of the transoms…we’ll see.
THe reason for the lengthy post is, by raising the motors, will I lose any noticeable abilty to trim the motors that is obviously required to control the boat??? We’ll see.
As always, I wouldn’t axe on a public forum if I was talking to myself.
And Skinny, glad to see you posting and I know you gots a cat…and you never been short on opinion.
Also swapped the drives to have the counter rotator on the starboard side so the props turn toward each othe and give more combined thrust.
Stern lift is mentioned as a positive ie. changing to 4 blade props. Presently running 3x15 1/2x 17 with rpm of 6k at full load so it is propped correctly…FOR THE LOWEST motor setting. I would imagine the rpms will increase after raising the motors 2 notches…we’ll see.
I need this boat to make at least 1.5 mpgs or better to make the amazing ride worthwile. We’ll see.
With a monohull you steer and throttle … with a cat you judge wave pattern/direction.
