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I am frequently sailing my Weekender and have recently added a reef point to my "Tarp" sails.  First time that I tried to use the reefed down sails, I noticed that there is an increased amount of stress on the sails at the reef grommets along the boom because of less Sail Area holding up the same amount of boom weight.  Even though these grommets are reinforced...they are not as strong as the edge of the sail seam that has some rope to help distribute some of the stress, plus there are more grommets to hold up the boom weight.  I don't know if this is clear or not....but my question is has anyone tied a line from the edge of the Gaff at the peak to the end of the boom to help take some of the stress off of the sails when they are reefed down?

Let me know if anyone has experienced the same thing or not.  My Sails seem to be getting really stretched and stresssed at the reef points from the boom weight on fewer grommets.  It seems like just running a free line from the Gaff to the Boom end would work to hold some of that weight....??

Tracy 

A line from the outboard end of the gaff to the outboard end of the boom will not work.

Poly tarp sails are quite stretchy. If not overly stretched, they will return to about the shape they belong, once the pressure is eased. This said, they have limitations, depending on several conditions.

Fabric weight, thread count, denier, sail construction, sufficient reinforcement, sail shape, sail set and a number of other items can affect how the poly sail will tolerate heavier wind strengths. As a rule, they don't very well or at least for very long.

This is primarily because of the material's tendency to stretch. As wind strengths pick up, in an ideal sail, you want to be able to flatten the shape. This gives you more control, eases pressure on the attachment points (relatively) and keeps the foil from stalling and shaking itself to death. If the material stretches, it forms a baggy shape which increases pressures (just what you don't want) and the shape becomes less efficient (so it starts shaking and stalling). This is a dog chasing it's tail situation, the more wind, the worse it's going to get.

Poly tarp sails, as you've found don't like to be reefed much. Along the foot you may have a bolt rope, hem and other reinforcements. Along the reef line, you might have an extra patch of material and a flimsy grommet. This isn't as strong, as you've plainly seen first hand.

You could increase the reef nettle count, which is a good idea. Additionally, put some extra material under the grommets, say at least as many layers of fabric as the corners of the sail, plus one or two more. Make the grommet reinforcement patches progressive. In other words, place down the biggest reinforcement patch over the grommet hole area, then the next patch on top, but it's slightly smaller (say an 1" all around), then another also slightly smaller, then the grommet. This is how real sails are made and all the techniques used in real sails, work on poly tarp.

In the end, poly trap is a great low buck way to make a sail, but don't ask it to be a real sail, because it's not. It can't handle heavier wind strengths for long, it's not very durable and makes a terrible racket when it flogs.

If it's all you can afford, take care of them and consider using sailing tactics rather then a reef if you find you have to run for shore in building winds. Sailing with the sails partly stalled will ease the pressure on the attachments, reduce heel and you don't have to worry about a reef. Of course, this requires a diligent helm, but most don't go far from shore. If you do get into big winds and are way over powered, consider dousing the main and continuing under jib. Your boat will be back under control again, the heel angle will be manageable and your mainsail can't blow out.

I used clear duct tape to strengthen the sail at the grommets. The tape was hammered with a dead blow rubber mallet to more effectively bond the tape to the tarp



There are 3 partially overlapped strips along each side of the sail,  and 3 crossed strips, for a total of 7-8 layers to take the strain of the boom. There is a bit of stretch, the sails have held up well for the past 3 seasons. 



Hope this helps you sort things out.

Greg

Tracy I am missing the question.  When I reef I use the reef point at the frount and back of the reef point to reef the sail (the larger grommits) to hold in the reef, the smaller gormmits with a line are tied around the sail and not the boom. Like a loose footed sail there are only two points holding the sail to the boom. Both these gormmits are in the heavy part of the sail and next to a line in the sail. This will keep you from having any pressure on the smaller gormmits and stretching your sail out of shape. This is the way all the jiffy reefing I have ever seen is rigged. Bud

Bud has it right, those centre points don't really hold any weight, just the end two.  Paul's suggestion is good except dead downwind, if you are over powered and can't reef, don't head dead downwind where you can't "dump" wind from the main, just drop it and use the jib.

Thanks for the help guys! Being a fairly new sailor I knew that there was something that I was missing...now it makes sense that the middle grommets are to just tie around the sail and not hold up the weight of the boom.  The outside grommets with line running next to them are to hold the weight! An AhA moment.

Don't feel bad... I have been sailing my boat for years, and just last summer Ryerson's wife Annie pointed out to me that I should reef to the sail and not to the boom. Makes a difference to sail shape for sure.

Wow..I'm glad this question came up. I usually lash my reef point to the boom too. Heck I have a loose footed main, for crying out loud...makes perfect sense to keep it that way...Duh!