Hi, Bob,
It kind of depends on whether you are racing the boat or just fun-sailing. And it also depends upon the sailing conditions.
The racers use a lot of aft mast rake and a sloppy rig. The boat comes with an eight-hole adjuster plate for the forestay, and they replace it with a 10-hole adjuster so they can rake the mast back farther.
For the sidestays, the rule of thumb (or hand in this case) is that you take hold of the side stay and rotate your hand toward the ground. If you can turn it almost 90 degrees, that is about right.
If it is too loose, you move your shrouds down farther on their adjusters. If you are at the bottom of the adjusters and it is still too loose, you take off the adjusters and attach the side stay directly to the deck chainplate with a shackle.
How much you can rake the mast back is also dependent upon the mainsheet block system you have. You need to be able to sheet the sail tight, so if you are block to block and the sail is not in tight enough, you are raked too far back.
The reason for raking the mast back is basically the same reason as on the Hobie 16 – you want to get the center of effort more over the skegs and rudders so you can point better going to windward. And the reason for having the relatively loose shrouds is so the mast can tilt forward more when going downwind and so the leeward sidestay will be slack enough to allow the mainsail to go out farther.
We have one person in our fleet who rakes his mast radically back (even adds onto the 10-hole forestay adjuster). He is extremely fast in heavy air and very slow in light air. So take that for what it is worth.
Now, if you are just out fun-sailing, and you have light conditions and boat chop, the sloppy rig can be very annoying because everything keeps banging around and the shrouds keep jerking at their fasteners. So in those situations I like my mast raked a little less and my shrouds fairly tight.
Sorry I cannot be more specific, but not all shrouds and forestays are created equal in length, and cable stretches, so you just have to figure out what works for your boat. In my case, my mast has the least rake of any in my fleet, and I only have an 8-hole forestay adjuster. I would not be able to use a 10-hole adjuster, because my shrouds are too long and are already at the bottom of their adjusters. If I were to rake my mast back farther, the rig would be SO sloppy, the mast would probably jump right off its mast base ball. So I obviously need new shrouds that are, hopefully, a little shorter.
By the way, sails are another variable that can make a difference in how far back you can rake your mast. They are not all cut the same – even stock sails from different years. Some give you more room than others at the back. And my stock sail does not have to be sheeted as hard as some of the custom sails in most conditions.
