40ft cat: what’s the optimum bridle length and setup?

[CaptainRivet]

Hi all,
Is there an optimum length for the bridle on catamarans? Are there Formulas to calculate or best practices?
What’s best practice for the setup of the bridle:
A) two lines each end spliced an eye with stainless insert attached to each bow with a SS shackle and then a SS shackle to get both lines together and to that connect a soft shackle or piece of rope with a chain gripper?
B) one line each ends spliced eye with stainless insert attached to each bow with a shackle. In the mid just Loop knot with a chain gripper
C)that’s how I have it till now: one line and ends attached to the bows via a bowline, in the middle a loop knot. To that loop knot is a 10mm dyneema soft shackle (that connects to the chain) lashed to with a 3mm dyneema line. Because it’s lashed there is no movement between the two ropes, means no chaffe. The end with a bowline chaffe a bit more the splices eye and SS insert but I check the ends often and if worse the cut off the 30-40cm broken line and tie to with a new bowline knot.

Mine is 40ft cat, beam 6,50m and weight is 8.5t with all gear and tanks full. Using 18mm 3 strand rope for the bridle

I am revising my Anker gear and put a new bridle.
prepping the cat for a 10years world circum mainly on the barefoot route.
Thanks

[StuM]

Two lines with an eye splice in one end. Other end attached to cleats so that you can adjust the lengths of individual legs (allows offsets for different wind/wave/current conditions)

Each leg at full extent should easily reach the other hull to allow easy handling.

Forget about SS shackles and chain grippers, just use soft shackles.

[CaptainRivet]

Originally Posted by StuM

Two lines with an eye splice in one end. Other end attached to cleats so that you can adjust the lengths of individual legs (allows offsets for different wind/wave/current conditions)

Each leg at full extent should easily reach the other hull to allow easy handling.

Forget about SS shackles and chain grippers, just use soft shackles.

Bridle need to be attached to a ring under the cross member. Cannot run bridle to the cleats directly. That’s why I have a bowline at the end, if I really need adjustment I just relocate the bowline and shorten this end.

Need to go to the cleats to set up a bridle on a mooring but that goes over the Cross member, needs chaffe protections in several places and is far away from optimum but nothing else possible. Many have the same problem.

[StuM]

Originally Posted by CaptainRivet

Bridle need to be attached to a ring under the cross member.

In which case you can't use the optimum / best practive for bridle setup.

If you include your boat type in your profile, it will appear beside your name and helps people to give more appropriate advice for your particualr situation rather than answering what you asked.
(Your location is frequently also useful since this is an international forum and many questions tend to be location specific.)

[sailingchiro]

Don't know if it is helpful but mine is 50' with each side is 25'. Seems to work pretty good. I like to secure to deck cleat and adjust each leg to current for best angle to wind.
During hurricane anchoring, I have 100' that goes to mid ship deck cleats after wrapping around bow cleats as well with 50' legs. The mid ship bridle takes the pressure of the primary bridle. In case the primary bridle fails.