Main sheet location

[Bigjake]

From observing a few boats I have noticed that the location of the main sheet varied from 41 3/8 to 45 3/4 in. from the bow between boats. Any opinion as to the "better" location?

[Columbia]

That topic was a recent conversation with another member. I'm not an engineer but my instinct tells me forward. And is there a rule on that dimension? I'm very interested on others take.

Joe

[geeks2you]

To my knowledge there is no rule determining the placement of the main sheet exit placement. The real determining factor that needs to be considered is the sheeting angles that are changed by moving both the exit points on the deck and/or the attachment points on the booms. Since the sails are linked to basically the same amount of sheet travel (may be argued otherwise on a swing arm with some fancy routing) the distances from the pivot points of the booms to the attachment point on the boom for each of the booms determines the total available distance that the boom can move when fully sheeted out. By moving the exit point of only say the main, you can chance the total sheet out distance of just the main in relation to the jib. All my rigs are built so that at full sheet out, the jib is at a 90deg angle to the center line and the main is at ~85deg to the center line

(typed fast so tell me if this is not clear)

Eric Olson
Atlanta Model Yacht Club
AtlMYC.org

[Rick West]

Jake,
Try the search function of this site for a specific subject. It works well for subjects that have been brought up before.

Eric has covered it nicely. The other aspects of where you would like the fairlead depends on the amount of resolution to the movement you would like have vs maximum sheet out. The further back you are and still have full sheet out ability the smaller increments to the sheetline in movement.

It depends on the model RMG winch you have and the number of max turms available, and to some extent the design of the drum, what your max winch line travel will be to start. In the old days we fought for 15-3/4". Now we can get well over that with the 280DL and EL to the point we have to set the max sheet out point short of its ability with the TX.

Any of the numbers you mentions during your observations will work if you have a 280 series. There is not a "better" location but that which will work for you. If we did have one, all would be on it

I favor the 45" and the boom attach point directly over the fairlead because I am still within the max sheetline range. I take all I can get and with the DL model and lost the battle and had to shorten up the TX.


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