Spinnaker questions

**Wentworth** · 10-05-2009, 19:38

Hi All,
Hitchhiking and I are just about to order some 3/4oz spinnaker fabric for winter tarps, but I read a slightly worrying passage from a DIY site:

"A lighter 'silicone' spinnaker fabric at 34 gsm can be obtained from several sources (typically yachting suppliers) but the samples I have tested and used are not as waterproof (~30kPa) and even this rating is not guaranteed. It was designed as an unwettable but light spinnaker fabric, not as a tent fabric.

It is rather stiff and crinkly and makes a lot of noise in the wind. I suspect that the proofing is actually a combination of a silicone polymer and polycarbonate (PC). The PC gives the fabric considerable dimensional stability: just what you want in a spinnaker. Creasing of the polycarbonate can present a long-term problem of worse leaks. This fabric is available from several sources here in Australia and overseas, but you should hesitate if you want something for the long term."

Is this right? I understood that the waterproofness (if it's a word) of Spin was better than silny?

**Cannibal** · 10-05-2009, 20:00

Probably depends on the source. My Spinn tarp from OES is flawless and I haven't noticed any issues with the Spinn I ordered from ThruHiker.

I love the stuff!

**warbonnetguy** · 10-06-2009, 12:19

spintex is a particular kind of spinnaker fabric, just because it's spinnaker fabric, it doesn't mean it's going to be waterproof, just like not all parachute fabric is silicone coated and waterproof.

the "spinn" being used as tarp fabric is pu-coated, which is why it's "more" waterproof than silnylon. alot of spinaker isn't coated at all except for the stabalizers they use, which make it feel like it may be coated but it isn't.

i believe the quote above may be wrong. from my understanding, sailcloth will "never" be treated with silicone because seam stick isn't compatible with it and sailmakers wouldn't buy sailcloth they couldn't seamstick. i have had several sailcloth manufactuers tell me this.

**HitchHiking** · 10-06-2009, 16:51

yeah its a pu coated spinn from a kite store. I was also talking to a guy about half ounce ripstop as well. Said a bit more strech but could work. may have to proof it yourself but.

**warbonnetguy** · 10-06-2009, 18:43

alot of those sail fabrics are listed by the sailmakers yard 28.5"x36" and also before the coating. don't get your hopes up on 1/2oz waterproof fabric because you'll probably be dissapointed.