ISIS mk2 Tuning

[Tony Berni]

hello, can anyone supply a basic tuning guide for the ISIS mk2, thanks

[Trevor]

I had a good look for some when I got mine and came up with nothing. The advice from the designer was non specific. The best I found was on sites like Sails Etc with generic setup/tuning instructions. Set the mast rake so the centre line of the fin intersects the masthead. Set the jib boom to just clear the mast. Then follow the generic instructions. Good luck. 

[P Cropper]

Barry never gave out any specific rigging guides however having sailed with him and had a few of his boats the following seemed to work.

set up boat and with rig tight, place on stand and measure from bottom to stern and bottom of bow, move boat forward/ backward so measurements are the same. With A rig the mast should be 0/1 degrees aft. with a straight mast. if you have an iphone then there is an app you can use to find out rake if you hold the phone to the mast, anotherway is to sight the mast against a known upright (room corner/ window frame ) and give the mast a slight aft rake.

tighten jib and back stay and check rake again and adust if required.

check the main leech on each side and adjust shroud length to give the same twist on each gybe.

jib boom should point at the shroud and main 5mm off centre going to windward.

That should only leave the mast ram to set main twist and that is non design specific and depends more on wind/water conditions.

The MK11 had a higher bow and that certainly improved performance downwind in a blow.

Rigs B and C more rake and ease sheets a bit.

Enjoy.

 

 

 

[Tony Berni]

Thanks for all your help 

[Tony Berni]

Sorry, can explain this a bit more “place on stand and measure from bottom to stern and bottom of bow, move boat forward/ backward so measurements are the same. 

[Eric Finley]

I'm sure Peter will be back to clarify! 

I believe that what you are doing is setting the boat up in the stand as if it was floating on water, The bow and stern both just kiss (touch) the water if it were floating in a tank with no outside influences (wind / waves). With the boat now horizontal along it's waterline you can determine the rake of the mast. Which if it is the same as my Psycho (The follow on design from Barry C} will be approximately 1 degree towards the stern. The closer you get the boat to level the easier it is to check the rake. Spirit level or laser level if available assist. If your club have an indoor measuring tank you could possible use that,

As Peter said, Barry did not provide set up guides. I purchased Barry's own Psycho when he updated to sailing his last design an Asbo. I asked if he had any guide for this boat and he just said he was a seat of the pants sailor and just set the boat up to the conditions and his preferred balance. So it was up to me!

Take a look at  https://www.nigelbarrow.co.uk/ where there is a lot of information regarding IOM yacht setup, There is also a page which will point you to sailing sites around the world which are of use, I have found the Plan B guide from down under provides a very good guide with lots of photo's of what your sails should look like.

Regards Eric

[Tony Berni]

Thanks for all your help 

[Eric Finley]

I should have highlighted this site as well:- https://dawsong8.wixsite.com/jgsails/tuning-tips

[Stephen B]

This is also very good and easy to see with pictures

 

https://rcyacht.au/set-up-and-tuning

[Tony Berni]

big thanks