2 Shrouds (Side stays) or 1

[Steve]

Did the original design have the shrouds more aft? If so,
I wonder how much more mast compression is placed on the cabin roof by moving the shrouds closer to the mast plate. Maybe the 563 roof problems stem from shroud chainplate placement changes that differ from the original design

Steve

[Yara50]

Did the original design have the shrouds more aft?

No, the original design is the standard with only a slightly aft location, and the backstay.

Most of the compression downward force from the mast comes from the balancing reaction to vertical forces from the windward shroud when the boat is healing under sail pressure. This force does not vary much with shroud fore and aft position. The uplift on the shroud chainplate, however, is greater in the design without backstay, as it has to also provide the forestay tension.

[Steve]

Hey Pete,
After having a bit of a think about your rig and after comparing it to mine, the way I see it an adjustable backstay, one that is tensioned through a block will cause your cap shrouds to loosen because the cap shrouds don't pass through the spreaders. I don't know if that would be a problem but it would annoy the be-Jesus out of me just knowing that when I crank on some backstay tension to spill some air out of the leech, my capshrouds are going to go loose. Maybe that's a good reason you have no adjustment on the backstay, It might be there just for looks or an antenna, or extra support to the mast when tensioned in conjunction with the capshrouds.

Steve

[Yara50]

an adjustable backstay, one that is tensioned through a block, will cause your cap shrouds to loosen

On a standard Investigator 563 there is a set of tensioning pulley blocks on the backstay. It does not have much effect on either mast bend or shroud tension due to:

• The mast is heavy non-tapered section, so resists bending
  The shroud chain plates are only slightly aft of the top, so if the mast was to move back, the difference in tension is minimal
  The shrouds are attached at the same height ("hounds") as the forestay, which also prevents the attachment point from moving much.

The shroud effect is there, but only tiny, and IMHO the benefit of a tight forestay is greater.

[Steve]

Thanks for that post Ian, It has made me realize my rig is the different one, sorry for any confusion Pete
Steve

[cruiserpete]

Thanks for the information, I imagine that the only way I'll know how my rig work is to get out sailing on it .... every piece of info is always helpful and it helps to balance out opinions and views