Melges 24 - Rig Setup

[ghoti]

Hi,

I know rig tuning on Melges 24 has been discussed to death but any good tips on getting finding base setting on the lowers. I know the North guide called for 3/4 inch sag on base settings (16 on the loos on caps) but getting out with the right wind conditions to find base is proving difficult.

Any good tips?

Alex,

 

[f-bomb]

A good way to find base tune for lowers is the Ullman method.

Ullman wants you to tune your uppers to base tension on the Loos gauge, then turn the lower shrouds to #18 on a Loos B tension gauge evenly, then loosen 15 turns (half turns if using open turnbuckles) for correct lower sag at base tune.

You can then sight up the mast under sail and adjust from there, for example we use North Sails jib and main, and only loosen the lowers 8 turns (half turns because we use open turnbuckles) from #18 on the Loos B gauge for proper shape/mid mast sag. We still use the North Sails tuning guide for working through the wind ranges, only using the Ullman method to find base tune though im sure it would work if we used Ullman sails.

The Ullman guide also has numbers for the Loos PT-2. The tuning guide and a pretty good tuning video are attached below.

Cheers

https://ullmansails.com/wp-content/uploads/2016/03/Ullman-Sails-Melges-24-Tuning-Guide-2014.pdf

 

[ghoti]

A good way to find base tune for lowers is the Ullman method.

Ullman wants you to tune your uppers to base tension on the Loos gauge, then turn the lower shrouds to #18 on a Loos B tension gauge evenly, then loosen 15 turns (half turns if using open turnbuckles) for correct lower sag at base tune.

You can then sight up the mast under sail and adjust from there, for example we use North Sails jib and main, and only loosen the lowers 8 turns from #18 on the Loos B gauge for proper shape/mid mast sag. We still use the North Sails tuning guide for working through the wind ranges, only using the Ullman method to find base tune though im sure it would work if we used Ullman sails.

The Ullman guide also has numbers for the Loos PT-2

Cheers

https://ullmansails.com/wp-content/uploads/2016/03/Ullman-Sails-Melges-24-Tuning-Guide-2014.pdf

Thanks for that guidance and the link. Ill give it a go!

 

[BrightAyes]

Ullman? Good lord I've NEVER seen a set on a Melges 24. Maybe a rare bird on the Left coast. The only two names in Melges 24 class are North and Quantum. Look at any startline photo and pick out a single Ullman. The simple answer is 16 on the uppers and loose on the lowers.

 

[ghoti]

Ullman? Good lord I've NEVER seen a set on a Melges 24. Maybe a rare bird on the Left coast. The only two names in Melges 24 class are North and Quantum. Look at any startline photo and pick out a single Ullman. The simple answer is 16 on the uppers and loose on the lowers.
View attachment 551726

Thanks BrightAyes,

no issues getting the caps right, problem is needing to wait for Base Setting weather conditions required to sight to the 3/4inch sag on the mast, to get the base for the inners before going out in other conditions.

At least the method above gets us in the ballpark, but open to other clever ideas.

 

[BrightAyes]

As long as the lowers can dance around inside a circle the size of US Silver dollar, you're good. Depending on your thread/toggle thread count: we use 3:2 ratio for each step up in wind condition. From a base of 16, we tighten the uppers/lowers 3:2 full turns, or increments of such: 3:2, 6:4. 12:8, etc.

 

[f-bomb]

@BrightAyes

As mentioned the OP was looking to find base tune on the lowers, and the North and Quantum tuning guides are a little vague on how to achieve base tune on the lowers. Ullman's guide is pretty good at explaining how to find base tune, even on lowers. All three brands base tune numbers are very similar/ the same.

I completely agree that its been a while since I've seen Ullman sails on the starting line, but Dave Ullmans tuning guide and racing guide/ tickler still contain valid information. I use North Sails upwind and downwind inventory on my M24 and could not be happier with them.

Cheers

 

[YabbaDabba]

We still use the tuning guide described in the article below as a base. It helped, in a big way, to get our confidence up in modifying the tune to different conditions. When we feel we have lost our performance or our memory of where we are (on the chart as shown in the article) we simply go back to our basic tune. Our rig tuner (most forward member on the rail) is really good at recording every change throughout the day, and you really can't be shy to change gears.

Talking Tuning with North's Nigel Young | International Melges 24 Class Association

Questions you wanted to ask about tuning your Melges 24 but never dared to ask…..Nigel Young heads up the North Sails business in Ireland and has been racing Melges 24’s since the earliest days of the class.

www.melges24.com

 

[Fourplay_004]

We set base at 16 on caps, and 13 on lowers minus 6.5 full turns (open turnbuckle).

 

[Pinner]

With the Loos PT1 and dyform / double threaded turnbuckle: 16 on the caps and lowers are 16 minus 12 half turns