What are the different fabrics and what's so great about them?

Silnylon

A view of the cutting board...


Silnylon

Ball burst impact testing in order to better understand the material properties of SpinnUL


I currently stock two different types of fabric - Silnylon and SpinnUL. Both fabrics are extremely lightweight, weighing in at 1.4 oz/yd^2 and .95 oz/yd^2, respectively.


Silnylon, short for Silicone Impregnated Nylon. Instead of a coating on both sides of the fabric (usually with urethane), silicone is applied before the fabric is woven, making an impregnation on both sides of the fabric. In this way, no water is absorbed by the fabric, so stretching and weight gain are kept to a minimum.

My Spinnaker Ultra-Light (SpinnUL) fabric is even lighter than silnylon while keeping all of the water resistant properties of the heavier fabric. Being a lighter fabric, it has a very slight decrease in tear resistance - as such, it would not make a terrific grouncloth. For tarps, however, I and many others consider it to be a perfect blend of weight, toughness and watershedding ability. SpinnUL tarps shed ~20-25% of the weight of an identical silnylon tarp!


Both fabrics share some fantastic properties. They are both self healing, so unlike urethane coated fabrics, they will not wick water through any small holes in the fabric. They are also more UV resistant than urethane coated nylons, although not meant to be used for extended use (many weeks at a time) in direct sunlight.


In regards to the SpinnUL, in addition to the weight, the major advantage of the SpinnUL is a lack of stretching when wet - silnylon has a slight tendency to loose a bit of its taughtness when exposed to rain overnight. The SpinnUL fabric does not have this issue. For silnylon, it 'looks' like a slight sag/few ripples in the fabric in the morning, but the catenary cut of the MacCat tarps and thoughtful pitching help eliminate most of the issues associated with this.


SpinnUL initially is a bit noisier than sil, but after a night or two of use, both tarps are identically nearly silent in all kinds of winds and weather. I also include a larger stuff sack as it does not stuff quite as small in the stuff sack(maybe 5% larger than silnylon). Once it's stuffed, it compresses down in your pack to nearly nothing, just like the sil version.


Both fabrics make for a fantastic outdoor product, and both have been working flawlessly in many tarps out on the trail. I have personally handled some of my tarps with 100+ nights on them, and they're still going strong!