MERLIN ROCKET FORUM

Topic : Tuning tips needed.

Could anyone send us link re.rig tuning/measurements for a superspars carbon mast with P&B main. P&B have a guide for most classes except this.

I came across a fact sheet (No.6-lowers and struts.) in the archive, how do you access the rest?

Went to Rutland at weekend left feeling like we need more power.

Thanks.


Posted: 25/05/2005 11:51:51
By: Paul
What weight were you carrying? We sailed Sunday, and we definately felt like we needed less power, especially in the midlle of the day we were at maximum de-power settings, admittedly we are a little light all up.

As a modern Merlin rig has a large variablity, as well as different hull design, there isn't a one size fits all measurment, like you can do with a GP14 for instance set it up by tape measure and its as fast as the next.

All the rig adjustments have to be made effectively 'on the water' and marked up when you find good ones.

The training fact sheet helps out with what string you might want to pull.

http://www.merlinrocket.co.uk/training/Fact%20Sheet%205%20-%20The%20Modern%20Rig.doc

Posted: 25/05/2005 13:42:08
By: Alan
Alan,

Thanks for that.

We're on the heavier side around 25st all up, sailing a CT...and the boats good.

What we noticed at the weekend was-while we didn't make many mistakes, even when it blew up and suited us boats with lighter crews were faster upwind sometimes even passing us out from leeward!

One thing for sure is that we need to adjust the spreaders...is there an optimum spec for these with the combo we have?


Posted: 25/05/2005 14:20:40
By: Paul
It is very easy to blame spreader settings and the like, often the more basic settings of rig rake are overlooked, even if you are slightly on the heavy side of light raking the rig when it gets windy makes the boat go faster, as soon as the top batten starts to back wind,or its hard work to keep the boat flat start to rake the rig.


Posted: 25/05/2005 15:08:57
By: Max Headroom
This will also depend on the luff curve that is cut into the mainsail but I seem to remember that the starting point for spreader deflection was from a line drawn between the tips of the spreaders to the back of the mast 14.5 cm. Then variances there on depending on other factors.


Posted: 25/05/2005 15:32:25
By: Spreader man
Lol,  were they lighter crews like Alsop/King, Stewart/Mee Calvert/Calvert?


Posted: 25/05/2005 15:37:49
By: Devils Advocate
Devils Advocate,

No certainly not...Calvert et al were far too far away for us to notice them.

Our dilemma is that we have a modern merlin that seemed to struggle against similar boats at the back of the fleet.


Posted: 25/05/2005 15:51:19
By: Paul
There are so many factors that could be not quite right!  I'm not exactly sure of the spreader setting, but a quick call to Tom at P&B would give you the answer.

It's not all about the spreaders though. Rake is important - even if you think you're heavier than the boats around you, it is important to rake sooner rather than later.

Lowers are critical. They can alter the amount of power available radically. Too loose and you won't go anywhere, too tight and you won't go anywhere either. I trust that your rig is fully calibrated - if it is then the thing to do is set it up with the mast vertical and not at all inverted with the main up. See how much control the lowers have and then set so they're not inverting it etc. This should be a good starting position. Then go out sailing and for a ball park you can play with the lowers a bit and see when the 2nd telltale down (on the main) starts to fly. It mightn't fly properly, but if it's making an effort then you're somewhere close. It's important to remember though that the kicker acts (through the gooseneck) at pretty much the same height as the lowers, so as you grind on more kicker, pull on some more lowers. I seem to remember that you need a bit more lowers on a superspars mast because the bottom is a bit softer than a Chipstow.

Shrouds should be just taught on the leeward side.

Don't stuff! With a Winder boat and P&B jib, the jib cars should be approximately halfway down the track. If you can't sail on the wind (i.e. too much power) then rake. Stuffing doesn't generally pay in a Merlin.

Hope some of this helps but most important is to practise and compete against other merlins - you'll soon work out what makes them tick, and the satisfaction when you get it right is amazing!


Posted: 25/05/2005 16:47:51
By: Chris D
Did you just have too much rake on?


Posted: 25/05/2005 16:48:39
By: Leaning forward
Thanks for the replies...we're working on it.


Posted: 25/05/2005 23:41:15
By: Paul

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