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why does my boat Rooster tail

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Steven Tunnacliffe
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why does my boat Rooster tail

Post by Steven Tunnacliffe »

Hi All

As the subject implies my boat Rooster tails in strong winds resulting in a loss of stearage and control is there a reason and a cure for this as my previous boat did not suffer from this problem?

Previous Boat now owned by Cockey young upstart Ben my Son who made comment on my nice fountain as he overtook me, Not a happy Dad as Im not in front of him much any more :(

HELP
Steve

1959 Forever Young
Brian Phipps
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Re: why does my boat Rooster tail

Post by Brian Phipps »

Hi Steve, Provided the rudder blade is in good order and your technique is sound, it sounds like it is a rudder alignment issue. Alignment can change for a number of reasons including slightly bent tiller arms caused through an incident or by over enthusiastic handling.
Sugget you check:-
1) Rudder blade alignment with the blades down, front edge to back edge . The newly avaliable, class legal, adjustable connecting bar end may help you there see item 20028
2)The rudder bolt area , washers, sleeve etc are all firm with no movement. See rudder blade service kit item 20002
3) Rudder buffer at the bottom of the rudder stock a frame , that supports the bottom of the blade side to side as well as acting as a buffer. item 02047
4) Your rear beam clips are snug against the hull to prevent any rear beam movment when you sheet on and create compression at the bow.

Hope that is good for a starter.
Brian Phipps
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Andymac
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Re: why does my boat Rooster tail

Post by Andymac »

Brian Phipps wrote:The newly avaliable, class legal, adjustable connecting bar end may help you there see item 20028
I take it the proposal posted in NewsSprint has now been adopted then? Sorry if I have missed any subsequent communique on it.
Funnily enough I bought 2 standard con bar ends from Brian in May, he mentioned then that the Dart 18's had adopted them but were yet to be considered by The Sprint 15. So I took the standards...academic to me at the time, because he was out of stock anyway and I don't believe I have the problem on 733.
Sensible piece of kit anyway.
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George Love
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Re: why does my boat Rooster tail

Post by George Love »

The resolution to adopt the adjustable tiller connecting bar was carried at the recent AGM held in Pwllheli at the Nationals.
It is therefore now class legal
George Love : Fly-by-Wire : 2019
Steven Tunnacliffe
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Re: why does my boat Rooster tail

Post by Steven Tunnacliffe »

Cheers Brian

The rudders are in fairly good condition and my technique hasnt changed (Cocky young Son gets rooster tails when he sails my boat 1959, and not when he sails 1343 his boat in same winds on same day) I did take about 5mm off the con bar not long after I bought the boat this seemed to improve the problem, maybe I should have taken off 10mm, or added 5mm :?

I have checked my rudders as they come home with me every time I sail I have tightned my A frame up as both had quite a bit of movement, both rubber buffers are in place and in good order. :)
When you say rudder blade allignment front to back do you mean that the measurement of the front of one rudder to front of other rudder should be the same as the back of one rudder to the back of the other rudder when lined up and secured on the boat :?:

Guess that will have to be done at the weekend when I go up to the Club :D

Thanks for the help
Steve

1959 Forever Young
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Steve Willis
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Re: why does my boat Rooster tail

Post by Steve Willis »

Hi Steve,

Rudders and alignment of hulls, I spent a happy couple of days on 756 a couple of years ago when I got rooster tails and poor beating performance. I even built the 'boat table' that now sits in the SSC field so I could do the alignment with the hulls hanging from the beams that rest across the table.

So have some fun with the following checks.

Do some checks on the hull castings. The bottom pintle pin can get bent either into a bit of an 'S' or over at one angle - try looking down through the top 'eye' and you should be able to see the pintle pin clearly all the way round its circumference. i have had to change a couple on our 15s and 18 that got knocked sideways coming ashore in heavy NE at SSC.

In addition check the distance across the boat between the centres of the two top 'eye' castings and the bottom of the two pintle pins - should be the same. TIP- Get a bit of 2x1 timber and notch it near one end and then use that to measure across to the other rudder or hull in all the following - marking the wood with each measurement.

When I was checking alignment I found that although both of the top eyes were done up tight when I loosened the port one the hole through the hull had elongated and allowed the casting to move 2-3mm sideways (which equates a a lot more at the area of the blade underwater.

If you can get your boat on a trailer with both rudders down and the con bar on you can get someone (Ben !) to align one or other rudder with the skeg line as you look underneath from the bows. With the rudders held in that position check the other one along the other skeg line and see if they are in line.

You can also check the vertical alignment with the rudders on - with the rudders straight from looking along the skeg lines keep the con bar in position and then measure between the blade tips and then at the front and back of the blade where it enters the casting and make sure they are the same.

If you get any discrepancies, before you start adjusting rudders check the hull alignment by measuring between the hulls at the front waterline, at the skeg under the front beam and between the skegs at their lowest point - all should be near enough the same. If not check the beam brackets and the wear on the hull where the brackets touch. I found my hulls toed in by nearly 15mm at the front and it was due to a couple of mm hull wear at the front brackets - packed them out with neoprene to stop the wear and cushion the hulls (3mm each side got rid of the 15mm at the bows) - then I adjusted the rudders properly.

Lastly make sure your blade buffers (in the bottom of the A frame) are not worn away. i do rudder repairs for a number of our Darts and Sprints and often find the soft rudder broken, worn away or missing. Again I use harder neoprene to stop the rudder movement in the down position.

How tight your hulls are on the beams and tramp tension also play a part. Any slack in the beam sockets means the hulls can twist in our out vertically as you apply pressure during sailing - changing the hull and rudder angle. Do you get any 'klonks' as you go about - indications of wear. Last of all check the stainless steel brackets on the outside of the rear beam sockets are adjusted up to be touching the hull. On most boats they can be adjusted by slackening the 10mm nuts visible in the beam and sliding the bracket in or out (slotted holes) and then make sure they are tight.

It has been suggested to me that if these come loose more than once then you can remove the nuts and washers and pour some fibreglass resin into the the slotted hole and then quickly replace the nuts and set the brackets in position - the theory being that the resin fills up the unused bit of the slot but that is a bit too drastic for me.

Hope you get it sorted, have fun !

Best wishes

Steve
Steven Tunnacliffe
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Re: why does my boat Rooster tail

Post by Steven Tunnacliffe »

Hi Steve

Good to hear from you, Ben and I havnt forgotten our friends at Seasalters and with a little luck we should be back to see you down there soon I hope. :D

That is a very comprehensive list and will take quite some time to check them all out so I shall have to arrange a nice fine sunlit day at the club with little wind, that is asking a lot of the rather chalenging moorland above Halifax :!: But I will look on the bright side the so called summer is now over and the weather should improve :o :lol:

I will go up midweek not on a race day as I dont want to be in a rush to get out there (racing), wont do it tonight as its our last wednesday night sail for the season. :(
Steve

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Steve Willis
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Re: why does my boat Rooster tail

Post by Steve Willis »

Cheers Steve,

Glad to hear you are in action and back into tweaking for performance. We do hope you and Ben can get back to SSC sometime, it was a great TT this year but pretty heavy duty. Hope the Wed night sail was good, Joan and I got out Sunday late afternoon for a thrash in F5+ just before the gales arrived.

Steve
Steven Tunnacliffe
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Re: why does my boat Rooster tail

Post by Steven Tunnacliffe »

Steve

Sunday up here in the North was sunny and virtualy wind free even on the moors at the sailing club, the only reason I went up was to do my OOD duty :( :?

I tried to abandon the racing through lack of a wind in any direction and refused to set a course but 13 monohull sailors wouldnt let me leave , so I made them drift around for about and hour each for the first 2 races :twisted: but only wore them down to 5 for the last race, but there are worse places to spend a sunday afternoon :)

As for me back in to racing mode, its coming along well I can sail in any wind I used to sail in and be competetive, we had a Trophy day two weeks ago and I beat ben in one of the races the race officials tried to give me trophy for said beating of Ben but they didnt have one spare :)

I have now got to build myself up to doing two days of racing and then I should be back on the circuit I hope :D

Other obsticle in the way of being back to full form is that I havnt capsized yet and dont know if I can right the boat :roll: I have said I will do it on purpose before the end of the season as its a hurdle I must overcome :wink:

As for Wednesday Night Ben was late home from work and we need an hour to get to the club and set up the boats so we missed the last midweek sail but went up to the local Pub (local to the sailing club) and had a pint with our friends :D
Steve

1959 Forever Young
Steven Tunnacliffe
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Re: why does my boat Rooster tail

Post by Steven Tunnacliffe »

It was blowing up a bit on Sunday and I am happy to say that all the advice from Brian and Steve W have cured the rooster tail effect and I scored 3 3rd places in the mixed fleet racing in the force 4 gusting 5 winds what a cracking day :D

Thanks Guys, see you out there on the circuit again soon :D :D
Steve

1959 Forever Young
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Steve Willis
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Re: why does my boat Rooster tail

Post by Steve Willis »

Great result Steve :D

Steve
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