Can You Re-Treat/Refresh Sil-Nylon?

ID was the first company to offer silnylon in our vicinity a couple decades back or so. Still have several of their tarps. A friend had the exact shelter you show and in hard rain he was complaining at the getgo of water misting through the fabric as he watched from his bag. Some users bought a tube of silicone caulk and diluted it with paint thinner then brushed it on. That adds weight and kind of sticks together so not a great option. And if I’m looking for shade ID silnylon is the last fabric I’d choose. The sun burns right through the two colors I own.

Interesting. Mine never leaked.

if you’re using it for shelter for day hikes maybe just use it as is.  It doesn’t have to be super waterproof.

If you use it and it leaks annoyingly, then treat it.

Erect tent inside out.  Coat with a solution of 10:1 mineral spirits:100% silicone caulk.  You don’t want the eco friendly/non flammable version of mineral spirits.  You have to stir it a lot to get it to mix into a thin syrupy solution.  Then coat tent and let it dry for 24 hours.  Or there are other versions of silicone caulk.

if you’re using it for shelter for day hikes maybe just use it as is.  It doesn’t have to be super waterproof.

If you use it and it leaks annoyingly, then treat it.

Erect tent inside out.  Coat with a solution of 10:1 mineral spirits:100% silicone caulk.  You don’t want the eco friendly/non flammable version of mineral spirits.  You have to stir it a lot to get it to mix into a thin syrupy solution.  Then coat tent and let it dry for 24 hours.  Or there are other versions of silicone caulk.

Thanks!

Was thinking along the lines of what you recommended, to just leave it as it and use it as a sun/shade shelter if I decide to not go through the hassle/effort of treating it.

That’s right it was mineral spirits with the silicone caulk. It’s been a long time since using it to seal the seam running the middle of the ID tarp and our Tarptents.

Here in the UK we have Fabsil Gold, which is exactly what you’re looking for, a silicone based retreating liquid. You can spray or paint on with a brush. Works amazingly well. Not sure how available it is in the States.

If you are going to retreat the tarp, per Jerry’s instructions, I would suggest a couple changes.
1) Use 15:1 by volume, mineral spirits/100%silicone caulk.
2) Do BOTH sides of the tarp.
It does a great job, but will wear out in 10-15 years.
Sometimes, the fabric seems good but starts to get weak after exposure to sunlight. Stretching can also be a culprit after 10 -20 years with it. Individual fibers in the weave can open up sections (usually near poles.) While not usually as bad as a real leak, the silicone can be compromised. (They often “knife” it on at the factory leading to very thin coats.) It can drip, seemingly from condensation. In either case, the silicone treatment will repair the waterproof layer. It usually adds between 1/2oz to a couple ounces for larger tarps.
Doing inside and outside will allow the silicone layer to stick to itself making a more waterproof coating and a longer lasting one.

I use a can of ordinary silicone spray on my blue tent (which is old), maybe once every few years. Seems to work fine.

Just for people who do not know this: NEVER try to mix silicone and fluoropolymers. They DO NOT MIX! If you do mix them, nothing will work thereafter.

Cheers