Thread and uv

[pcatterall]

Just about to resew the cockpit cover and Genny strip
I know I will have to get the right thread (any advice ?)
I just wonder why the sewing thread always goes but the material threads (the warp and weft) remain sound??

 

[RichardS]

I spoke to a sailmaker about this and he said that the threads normally used are indeed all more susceptible to UV degradation than the sailcloth. There is some kind of UV-resistant sail thread but it is more expensive and more difficult to work with and sailmakers are not keen on using it.

Richard

 

[vyv_cox]

The UV resistant stuff is PTFE. Expensive to buy and difficult to work with. My stackpack is sewn with it, which cost me an additional £75. I reckoned it was worth it, having restitched almost all our much simpler canvas over the last couple of years.

 

[Ruffles]

Dabond is suposed to be very UV resistant. But the flap over the zip on my sail cover came off in my hand the other day at around 6 years old. Not great. It's Dabond V69. Perhaps thicker thread would last longer? It's available in various sizes. Not cheap though! I think I'll just restitch over the top!

V69 breaks at over 10lbs. So it's quite strong. I have some V92 which is 1.5 times as strong but I suspect near the limit for a domestic machine.

The fabric is acrylic. The thread polyester I guess.

 

[KellysEye]

Dabond UV resistant thread. An example is here: http://www.sailrite.com/Thread-V-92-White-Polyester-UV-1oz-250-Yds

 

[Plum]

Dabond UV resistant thread. An example is here: http://www.sailrite.com/Thread-V-92-White-Polyester-UV-1oz-250-Yds

I have used this too, although from a different supplier, and I find it lasts for 8 years when exposed all year (inth UK sun!)

Colin. Www.solocoastalsailing.co.uk

 

[wilkinsonsails]

V92 bonded thread is really the minimum needed for covers and sails exposed to the Uk weather.
Med less than 4 yrs is a common timescale.Tenara thread can solve that, but will cause problems with a domestic machine .Needle size and tension adjustment being one .
Cindy

 

[ip485]

Yes Tenera is the stuff. Will outlast the fabric. Its a deal more expensive and not quite as straightforward to machine sew, but once you have set up the correct tension and needle, its fine - well at least on my Sailrite. It would seem it really is amazing stuff, perfect for any covering although I gather the sailmakers seem to have some reservations, but I am not entirely certain why.

 

[wilkinsonsails]

Tenara thread ,It's quite hard and inflexible ,a bit like sewing with fishing line ,and does not bed in on softer fabrics such as acrylic canvas.
.This can make it prone to snag,It also needs the machine set up to sew with it which requires a bit of patience and fiddling .Tenara fabric does exist but it's pretty expensive so we rarely mention it .

 

[pcatterall]

Thanks all, that's good info concerning UV resistant thread.
BUT can someone help me understand why my canvas and sail cloth far outlasts the thread it is sewn with. If I could unpick the warp threads from ( say ) Sunbrella fabric and use this to sew seams how long would that last?

 

[lw395]

Thanks all, that's good info concerning UV resistant thread.
BUT can someone help me understand why my canvas and sail cloth far outlasts the thread it is sewn with. If I could unpick the warp threads from ( say ) Sunbrella fabric and use this to sew seams how long would that last?

Not sure if Sunbrella has a coating applied to ward off UV?
Or whether acrylic is just too stretchy to use in a sewing machine thread?
Here in the UK, I've just had to make some repairs to my dinghy cover, it's about 5 years old. The fabric (Weathermax) is great, the thread is fine, the problem was bits of webbing which were completely shot.
Stitched new webbing on with ordinary domestic Bernina.

Nikwax do a UV resistance and waterproofing product. Maybe that would protect the thread a bit? Are there any other good anti-UV products for fabrics?