Self-Adhesive UV Dacron for Sacrificial Cover

[thinwater]

I have a laminate jib that needs a new cover.

1. Sewing one on is probably a non-starter; the needle holes will start a tear-here line.
2. Yes, I could get a new sail, but this one still had nice shape, so I would like to get a few more years out of it.
3. Yes, I know polyester lasts longer. The replacement will likely be polyester or Hydranet.
4. No, Sunbrella is not a possibility. I like it on polyester sails and have had several, but on laminate sails it is a mistake (makes a stiff spot, which flexes the Mylar, leading to tears). It is a bad mistake on older laminate sails.

My question is, will the SA cover stay on if I skip the stitching? I've never had insignia cloth or tape repairs come loose, so I am wondering if it could simply be pressed on. I'm not looking for perfection.


So, has anyone actually done this or have personal knowledge?

[s/v Jedi]

I have used Insignia tape and it never came loose, but not for the UV cover of my jib, which is Sunbrella. I think it would work, but I don't know how it would go across seams and not so sure it's available wide enough for the cover?

Edit: for sewing you need a machine with the 3-step zig-zag

[thinwater]

Originally Posted by s/v Jedi

I have used Insignia tape and it never came loose, but not for the UV cover of my jib, which is Sunbrella. I think it would work, but I don't know how it would go across seams and not so sure it's available wide enough for the cover?

Edit: for sewing you need a machine with the 3-step zig-zag

SA UV Dacron is available in a variety of widths up to 18 inches.

My last laminate sail had a cover professionally sewn on with a zig-zag stitch. It developed several tears, up to 4 feet long, right along the stitch line. No fibers failed, only the Mylar. In fact, the tear was easily repaired with tape, which holds to this day (back-up sail). In fact, the only failures in the sail were on the UV cover stitch line. Isn't that something? I discussed this with several sailmakers, and they all blamed the cover and the stitching.


Laminates are new to me, so I'm all ears.

[MartinR]

I remember somewhere on this forum there was a thread about painting the suncover instead. It has been done successfully it seems. Just a thought.

[s/v Jedi]

Originally Posted by thinwater

SA UV Dacron is available in a variety of widths up to 18 inches.

My last laminate sail had a cover professionally sewn on with a zig-zag stitch. It developed several tears, up to 4 feet long, right along the stitch line. No fibers failed, only the Mylar. In fact, the tear was easily repaired with tape, which holds to this day (back-up sail). In fact, the only failures in the sail were on the UV cover stitch line. Isn't that something? I discussed this with several sailmakers, and they all blamed the cover and the stitching.


Laminates are new to me, so I'm all ears.

There is a big difference between a zig zag stitch and a 3-step zig zag stitch. It exists to prevent this problem.

[thinwater]

Originally Posted by s/v Jedi

There is a big difference between a zig zag stitch and a 3-step zig zag stitch. It exists to prevent this problem.

Good point.
The problem that is even harder to avoid, is that the weakening seems to concentrate at the stitching, but also extend ~ 1 inch forward of that. The problems seems to be that the sail flexes excessively due to the stiffness of the covered area. In this case, the solution I intend is to use a slightly wider cover so that the flex area moves ~ 4 inches forward to fresh cloth.

This is also the reason I am considering UV Dacron instead of paint (I've been testing some paints, and while house paint is a failure, there are others that would work) is that the sailcloth could do with some reinforcement. Two birds with one stone.

[Bill O]

How about a jib sock instead of adding additional material to your sail? Could make it out of Sunbrella for outstanding UV w/o adding anything to your sail.


Bill O.

[mikereed100]

Years ago I used adhesive polyester for a sun cover on an older jib. I sewed it as well, so maybe not so pertinent to your question, but, as I recall, there was no loss of adhesion between the sail and the cover over the few years that I used it before replacing. This was on a Dacron sail. I wonder if adhesion might be even better on Mylar, assuming there is no taffeta?

[Calif.Ted]

I use a sleeve on laminate headsails.
Genoa Sleeve | ATN Sailing Equipment

[hellosailor]

And here I've never found a self-adhesive "sail repair" tape that stayed on for even one season. Thinwater, I'd suggest you find a specific brand name, ask them about proper surface prep, and try a test piece. It just might stick better to the smooth laminate and do the trick.

[JPA Cate]

Have had sticky-back dacron stick to repairs without stitching, but on dacron sails, so may not apply for laminates. Stuck for the life of the sail, as a matter of fact, many seasons. We prepared the fabric for the patch by washing the area with acetone on a paper towel. I do not know whether it is safe to use acetone on the laminate, but perhaps methylated spirits (alcohol) would be good enough to make sure the surface is really clean.

I think the painting idea sounds easier to achieve, and probably a good washing beforehand, of course: the surface should be very clean and also, dry.

Ann

[s/v Jedi]

I use Bainbridge Insignia tape and that sticks for life. On high abrasion areas, after it has become very thin, it still has 100% adhesion. In storage this stuff stinks... I'm happy to have it in an air tight Pelican case

[Kestrahl]

If you don't sew it, it will creep and bunch up.
Sewing with three step zigzag creates more weakness as it creates more holes. The purpose of using three step is to create a seam which is less prone to creeping ( i.e. 2 rows of three step is equivalent to 3 rows of regular zigzag )
Generally UV covers should be sewn with regular zigzag as they are a lot faster to remove and replace.
In this case with the adhesive dacron UV cover you can sew it 2cm in from the edge and it won't create any weakness ( and outside the existing stitch holes ).