When you buy a Tarp Tent, a silnylon tarp shelter, or a hammock tarp, it’s best to seal the seams using McNett’s Silnet (also called Gear Aid Silnet) in order to make them waterproof in the rain. Most of these shelters are not seam sealed or seam taped, so you have to do it yourself.
Here is my simple guide to do that.
- A brush that you don’t mind throwing away afterwards
- A tin can or something to mix up in
- A bit of card, or a very steady hand
- Damp cloth
- Mcnett Silnet, which is sticky messy stuff
- Paint thinner
Start with mixing at 3 to 1 paint thinner in a tin with Silnet until it is a workable viscous paste that can be easily applied with the brush to the seams. The whole point is to get it to soak into the stitching where the water could penetrate. If you were to apply the Silnet without thinning, it cures too thick and can flake off leaving a messy look.
Note: You want to seal the seams on the outside or top face of the fabric only. One coat is usually enough. Really.
Pitch the shelter in good weather or the garage: somewhere where it can dry for most of a day. Pitch the tent or shelter tightly, as you would in the field. If it has an unusual shape that makes it impossible to seal all of the seams at once, do them separately on a different day.
Brush in the thinned mix carefully and use the damp cloth to mop up any spills. A little goes a long way. A cut out template (shown above) will help reduce spills. The thinned mixture will soak in and look neat after it dries.
Written 2015. Updated 2017.Editor's note: Help support this site by making your next gear purchase through one of the links above. Click a link, buy what you need, and the seller will contribute a portion of the purchase price to support SectionHiker's unsponsored gear reviews, articles, and hiking guides.