top mast laced vs sail luff pocket. Advantages and disadvantages.

[david]

Hi all, I am looking for your experience's with the top mast being laced. Most of the photos I see are luff pockets. They are coming into the States with lacing. Does anyone know what the advantages are for one over the other? For me it is cosmetic as you have a nice wooden mast topped by a black carbon top mast.
 All comments are appreciated.

Regards,
D.

[Craic]

David,
the luff pocket was an innovation brought in to improve the aerodynamics of the mainsail and mizzen. Prior to that, all such yawls had laced gunters and mizzens. The idea came from watching windsurfers performing. It worked perfect, still would. You can still see the effect on the mizzen sail today.

However, Matt changed the gunter yard back to lacing in 2008 because one of his then sailmakers never got the hang how to avoid a crease forming under strain near the halyard window in the luff pocket, and because the system Matt then used to connect gunter yard and halyard (you had to insert the yard through a spliced eye in the end of the halyard and hook that eye then over a clamp on the yard which was covered inside the luff pocket) was less then ingenious and drew -understandably- flak from beginners.

Anyway, the luff pocket still offers the better aerodynamics, I have two boats with, and one without, and have the two systems in direct comparison so.

Maybe some people are happy with the laced gunter main, I am decidedly not, the only reason I still have the laced mainsail on one boat is that it costs a lot of money to have the original luff pocket retrofitted to it.

IMHO the lacing should never have been brought in again. It is a step back.

[Craic]

David,
I had forgotten the other disadvantage of the laced vs. the luff pocketed mainsail.:

To disassemble - assemble mainsail and yard takes a minute and little skill if you have the luff pocket, and it comes out perfect every time.
But without the pocket it is cumbersome and time consuming to unlace - relace the mainsail to the yard. And, unlike if you have the luff pocket, the lacing needs to be redone after a while and from time to time to get the recurring sagging out. And the laced mainsail tends to give creases where the laces go through.

One should take the mainsail off from the yard every time before doing larger distance trailering, because if you leave the sail attached, the rubbing and chafing from wind and vibration on the cockpit floor is pretty destructive for the sail.

[Graham W]

With a luff pocket, how do the various halyard positions for reefing the mainsail on a laced yard get translated?

[Craic]

With a luff pocket, how do the various halyard positions for reefing the mainsail on a laced yard get translated?

The sails have two additional windows in the leading edge of the luff pocket to tie the halyard to the yard at the corresponding reefing positions.
The other way is to have no windows but just through-holes through the pocket at the reefing positions, just aft of the yard.

[Craic]

There is one photo of a reefed luff pocket mainsail at the end of http://www.swallowboats.co.uk/images/stories/swallowboats/searaider/Craic_mods_791.pdf .

[Graham W]

That is clear, thanks Claus.

[Craic]

Graham,
it all hinges around how you connect halyard to yard. You know the trick?

[david]

Thank you Craic for your explanations. I found them interesting and informative. The photo is great. Really helped to see how to.
  One question for you on the comment in your last post.
*it all hinges around how you connect halyard to yard. You know the trick?*
  Can you let me know what the "trick" is please?

Thanks again for your help.

David.

[Graham W]

You know the trick?

Claus,

I too would like to know the trick. 

If I do not pay attention to how centrally my halyard is connected, my (laced) yard goes up squint to the mast, which is less than ideal aerodynamically.  I also suspect that my halyard is a little bit stretchy and am in the process of replacing it with a Dyneema version.

Graham

[Craic]

David, Graham,
the trick is simplicity. Drill a hole through the yard, put the halayard through it and secure from slipping with an eight knot. Nothing works better. All these other hooks and splices and fiddly assembling, ending in twisted yard and gap between yard and mast, forget it.
But there are details.:
- The through hole must be central through the yard, and no bigger in diameter than 8.5 mm.   
- If you wish to reinforce the yard in the area of the hole, sikaflex on a strip of thin hardwood (or one of these multi-holed stainless steel dinghy shroud adapters) ON THE SIDE OF THE YARD THAT FACES THE MAST. That is the stress side.
- No need for any reinforcement if your yard material is long enough so you can drill through the overlap section where upper and lower part connect.
- To reseal the yard for buoyancy, put in a blob of PU can foam into the hole. While the foam is still sticky and expanding, push an oil covered pencil through the hole to keep that open. The oil lets you retract the pencil after the foam has set. And after retracting you have a clean canal to put the floppy halyard end through the yard in one go.
- To finish, use an old length of rope through the hole and do some see-sawing to chamfer and polish the edges of the hole.
- And yes, best use Dyneema (Spectra) for halyard material.

I drill and use holes through carbon yards since my Drascombe days. And no, I never broke any of them in sailing, however hard I tried.

[Graham W]

Excellent! Another task to add to my to do list.

[Graham W]

Drill a hole through the yard, put the halayard through it and secure from slipping with an eight knot.

I think figure 8 knots may have a tendency to slip or undo in Dyneema, which would be, er, unhelpful. This link seems to suggest that a simple modification to the knot would solve that particular problem http://www.colligomarine.com/docs/misc/CMRStopperKnot.pdf Has anyone any experience of it in Dyneema/Spectra?

[david]

Hi All,
          I want to thank all who have replied to my posts about this topic and on the trailor I posted. I have taken the plunge and ordered myself a bayraider. It should be out here in San Diego sometime in June. Just in time for some great summer sailing.
  I was not able to get the luff pocket on the sail. So it will be laced. The sail makers were concerned there would be an issue and exchanging sails from the U.S. would be an issue.
  So, Thanks again to Craic, Graham W, Julian, Colin and Tony for helping answer my questions pror to purchase.

Regards,

David.

[Colin Morley]

Hi David,

I am sure the information you have been given is correct but I think we must not lose the perspective.
The purpose of having a BayRaider is to have a good boat which sails well. The effect of a lace or luff pocket are theoretical and I doubt whether they affect the performance in any measurable way.

I have a BayRaider 20 with a laced sail and she sails beautifully. I would not worry and enjoy what you have got.