Sagging Boom

[Default User]

When hoisting the main, I often forget to loosen the main sheet, which does not allow the main to go all the way up.

It results in an effect similar to what is described here.

Be sure to have lots of slack in the main sheet and be pointed into the wind when hoisting the main up.

If it can be figured out at all, this crowd will do it.

Good luck!

Dave

[Tomfoolery]

I would think that if the gooseneck was mounted higher than it's supposed to be, the whole sail would simply ride higher on the mast.

[BOAT]

I would think that if the gooseneck was mounted higher than it's supposed to be, the whole sail would simply ride higher on the mast.

Yeah, but not if the sail is already up as high as it can go - he said he pulled it up and it would not go any higher so he said it topped off. I figured if the top is all the way up, I guess the next logical place to look at is the bottom?

[Tomfoolery]

I would think that if the gooseneck was mounted higher than it's supposed to be, the whole sail would simply ride higher on the mast.

Yeah, but not if the sail is already up as high as it can go - he said he pulled it up and it would not go any higher so he said it topped off. I figured if the top is all the way up, I guess the next logical place to look at is the bottom?

That's true, of course, but from the pic, it looked like there was a lot of room to go up still. Though the head board could be stopped by one of several things, of course, like a giant knot on the halyard, an obstruction in the groove, even just binding slides (assuming it has slides), which mine does some times, at least until I replaced them with the correct size.

[BOAT]

Yes, I agree tom - don't get me wrong - I'm just fishing for clues - this thing is still a big mystery to me - it makes no sense.

I have blown up his picture beyond recognition trying to find a problem at the top of the mast but I am just too un-familiar with the D boat to make any recommendations.



I don't even know if Sumner would know ? he might know about the D boat better than us because he has an S boat.

I just dunno.

[Curwen]

Hello all,

I will raise the mast this weekend and get a better shot of the top of the mast with the sail raised. I've been on the water and never really took a ton of time in seeing if I could get it to go higher. Part of learning about your boat.

This is starting to feel like a popcorn kernel stuck in my teeth.

Curwen

[Tomfoolery]

Curwen

While you're at it, shoot a pic or two from below the boom, aimed up the mast (without the bright sky washing it out or making the sail too dark to see anything).

Also, check to see if the sail is tight against the tack fitting at the gooseneck when the halyard is tight. I'm betting it is, and the boltrope is shrunk and holding the headboard back, but if it isn't, the problem is at the top of the mast where the top slide or bolt rope is binding or otherwise being stopped. Or further down, where a single slide is binding - I've noticed mine do that sometimes as the sail is being raised, but since I replaced them with properly sized slides, it doesn't seem to happen.

And in the mean time, take a look at this thread. I had a shrunken bolt rope, along with an improperly terminated tack fitting, and the braintrust here got me right.

http://www.macgregorsailors.com/forum/v ... =8&t=23552

[Wind Chime]

Curwen,

Save yourself alot of head scratching and cut the bolt rope loose.

It's a two minute job, take a box cutter knife and cut the two or three threads down at the tack corner of the sail. Can't miss which threads to cut as these are the only ones that go through the rope all the other stitching is on the reinforcements pads etc. then just haul up on your main sail and should just go up the top. Having a free boat rope does not lose the integrity of the luff.

MacGregor started making D's in 1986 I believe, looks like you have the original sale on your classic. That's a long time with one sail so it doesn't owe you anything.


Judy B, Judy B, where art thou Judy B?
Love to hear your thoughts on this.

Darry

[Mike C.]

I have a 26D, and it came with the original main. I had the exact same issue. I tried some workarounds, but none worked.
call it shrunken bolt rope or stretched sail, end result was I bought a new main and the issue was resolved. Glad I did.

[Judy B]

Curwen,

Save yourself alot of head scratching and cut the bolt rope loose.

It's a two minute job, take a box cutter knife and cut the two or three threads down at the tack corner of the sail. Can't miss which threads to cut as these are the only ones that go through the rope all the other stitching is on the reinforcements pads etc. then just haul up on your main sail and should just go up the top. Having a free boat rope does not lose the integrity of the luff.

MacGregor started making D's in 1986 I believe, looks like you have the original sale on your classic. That's a long time with one sail so it doesn't owe you anything.


Judy B, Judy B, where art thou Judy B?
Love to hear your thoughts on this.

Darry

Here's a picture of a mainsail with a shrunken bolt rope:

The leech of the sail didn't shrink; it's about the right length.
The luff is too short. The old mainsail had a shrunken bolt rope in the luff. The luff looks very weird: The sailcloth is all "gathered" and wrinkled because the rope has shrunken

If you could hoist the head of the sail all the way, the end of the boom would be in the right place. But you couldn't raise the head of the sail all the way up to the top, because then the gooseneck would end up in the feeder slot of the mast, or maybe even above it.

The red lines are the old sail. The Green lines are what a new one will look like.


Also note that there are puckers all along the luff, from the shrunken bolt rope. That makes the sail look really baggy. Freeing the bolt rope so it can slide inside the luff will remove some of the bagginess. However, that leaves the dacron sailcloth to carry all the strain imposed by halyard tension. So a short piece of bolt rope should be butt-spliced onto the old sail, and then the bolt rope reseized to the luff pocket.


However, considering that the cloth is as ancient as the bolt rope, you really shouldn't expect it to hold a shape well after fixing the bolt rope. The shape will look better, but, like the bolt rope has lost it's structural integrity, so has the aged polyester dacron sailcloth. It too has lost it's ability to "return. " Threads have gotten brittle and are breaking. The flying shape of the sail will not be anywhere close to "optimal"

Releasing a bolt rope is a "stop-gap" measure most of the time. You can keep using it, but the boat will sail much flatter and point higher and steer more easily with a new sail.

The pictures I have shown here are of a really old sail, with really old bolt rope.

I'm sure some of you have heard about "pretensioning" bolt ropes. Traditionally on dinghies, we pretension the luff and use a "stretchy" bolt rope so that the shape becomes very full for downwind sailing. For a long time, all sailmakers pretensioned the bolt rope on yacht sails too. But since newer low-stretch, "hard" ropes have become available, most production lofts quit doing that (during the 1990's.) for yacht mainsails. For yacht mainsails, we use a pre-shrunken rope that has very little stretch to it. Newer, preshrunken synthetic "hard" boltropes don't shrink this badly.

[Plebian]

If it's a new sail, it's cut wrong or you aren't tightening the clew enough. If it's an older sail, make sure your leech line hasn't broken loose. Either way, if you don't have your battens in, it may sag a bit.