Sizing spinnaker sheets ?

[Sven]

I know they should be twice the LOA (or more) but I don't know how to determine the diameter. I assume that handling comfort would preclude very thin ones even if they are strong enough, but since I'll be buying 160' of it I want to go on more than assumptions.

Our recut asymmetric spinnaker is probably still close to 47' x 47' x 27' of .75 oz. cloth.

I haven't yet figured out how to route the sheets to the winches. The coaming cut-out for the jib/genoa sheets in the E39B with the aft helm makes those winches less than optimal for a spinnaker. I'm thinking we'll use the smaller cockpit coaming mounted winches with the sheets going aft to some new track mounted spinnaker sheet blocks. Maybe someone here has already tackled this problem on the E39B ?

I'm planing on getting/using an ATN spinnaker sock for setting and dousing.

I think the tack will be attached to a 4' pendant outside the pulpit, attached to the base of the forestay or some part of the anchor roller but I haven't yet dismissed having a tack line running through a 2-1 purchase block, back to the cockpit as an alternative.

Wisdom and insights welcome, as always.

Thanks,


-Sven

 

[Rocinante33]

Sven,

We have a stout padeye on top of the coaming at the aft corner. We attach a block to that padeye. That serves as a turning block for the sheet and we bring it back to the main winch. I think with spin sheets you want them to be led as far aft as is possible. I have to route the sheet over the lifeline and it usualliy just clears it. This is a simple attachment technique & it may work for you despite your larger boat.

 

[Sven]

Sven,

We have a stout padeye on top of the coaming at the aft corner. We attach a block to that padeye. That serves as a turning block for the sheet and we bring it back to the main winch. I think with spin sheets you want them to be led as far aft as is possible. I have to route the sheet over the lifeline and it usualliy just clears it. This is a simple attachment technique & it may work for you despite your larger boat.

Thanks Keith. If we place the block in the aft corner instead of all the way back on the track I think we would indeed be able to bring the sheet to the main winches. I'll check in a few hours when we get down there.

Thanks again,



-Sven

 

[ted_reshetiloff]

Cant speak to routing of sheets or tack set up for the 39 but for diameter I use 3/8 Yale Vizzion. It is fine on the hands and yet light enough for most light air. If you plan on carrying the sail in more breeze you may want to consider going to 7/16. Not for strength but for comfort. 7/16 would likely fit any self-tailing primary winches better too but would be a big drag in light air. If you want to go all out use something nice like Endurabraid and strip the cover. Dyneema core will hold up well to UV and be light but be thick enough where it needs to be. Proabably want to fly the sail a few times to see how much cover you want to strip. I also reccomend for an assym splicing the two sheets together then having an 18"-24" tail that connects to the sail. This makes gybes smoother.