first sail with strong weather helm

New to catsailing..Father's day first sail went well on Prindle 16 until winds picked up and had very significant weather helm. I expected the rudders or tiller to snap. 10-15 mph expected but gusting to 18+. I reefed before heading out with son#1 200lbs+ my 200 and felt we could have a great time. End of day winds picked up and once I added son #2 220lbs we struggled to maintain course. Not sure about the mast rake and will check it out. Rudders appeared to be locked but not sure of rake and need to take measurement to see where they are in relation to hulls. Traveler is currently useless and replacement has been ordered along with smaller line. I expected there may be some increase in weather helm as winds increased but not sure if the additional weight distribution, reefed sail, or my inexperience led to the struggle to maintain course. As dark skies approached we let the jib fly and maintained a reasonable course to safety. Bottom line we were all smiling as we beached and look forward to the next sail. Looking for suggestions that may help avoid in the future. icon_cool

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J.D.
1981 Prindle 16
1978 Y-Flyer
Akron,OH
USA
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http://www.thebeachcats.com/pictures?g2_itemId=89541

Check out my album on dialing in your rudders, once you have the rudders done, set the alignment with a slight "toe in" setting by measuring the distance between the leading edge, rudder to rudder, then measure the distance on trailing edge, rudder to rudder.

R
Are you absolutely sure that the rudders were in a full lock down position. You can check on land put raising the stern high enough and pull down to lock then see how much resistance there is.
Rudders not being locked down completely is the most common cause. Rudders should be slightly tucked under the hills. Also check rudder alignment. That needs to be parallel. The slight toe in is good too but that is very slight. Next mast rake. then it starts to get tricky.

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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I suspect he starboard side rudder may be the culprit. It kicked up earlier in the day. It was obvious that something was not right. Thanks guys for all the suggestions and link to your album (the-renovator). The pics are excellent and very helpful. The Prindle manual is a bit grainy and tough to make out all of the details. I will test and do some measuring over the weekend. Thx

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J.D.
1981 Prindle 16
1978 Y-Flyer
Akron,OH
USA
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Did you swap out sons or were you 3 up? 620 lbs on a Prindle 16? something is gonna give. Boat design load is probably like 360. You are actually overloaded 2 up but all these boats have a margin of safety, 3 up goes well past that margin. With a reef in the main and that much load it is amazing that you went anywhere besides where the tide was going unless it was a lake. Start looking for a Prindle 18.

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'life is too short to drink cheap beer'
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All three onboard..which will be a rarity. Second son surprised me on Father's day standing on dock so we picked him up. I will usually solo in a lake. I am very impressed with the P16. Appreciate your comments.

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J.D.
1981 Prindle 16
1978 Y-Flyer
Akron,OH
USA
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The P16 is great for solo sailing, glad your happy with the boat.

All catamaran design begins with design load and righting moment, the rest of the rig 'strength', sidestays, forestay, mast wall thickness, chain plates, buoyancy etc is based on the 'design loading.' Just something to keep in mind when you add ballast (crew). Wind pressure + ballast = tremendous rig pressures. Have fun and post some updates on the helm issue.

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'life is too short to drink cheap beer'
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