DCF stuff does seem to be the answer! Just looking forward to it being mass produced and therefore possibly dropping down in price a little 🙂
DCF’s been around since about 1990 (it’s called cuben because it was developed for the Americas Cup boat America3). It’s expensive because it’s expensive to make not necessarily the quantities. Even dyneema as a rope is expensive, the price is never likely to drop.
It’s strong and light, but not all that tough, even compared to similar weights of ripstop polyester. I.e. you can comfortably make a sail out of it that will take the weight of a car, but keep it away from sharp corners.
Cordura is a form of nylon which is tough, but also stretches when wet, which makes it great for a tarp you want to wrap around yourself as a basic tent and groundsheet, but will get flappy over night if it’s wet and windy (why else would you have a tarp though). A bit of stretch is no bad thing though if you want to form your tarp into a shape rather than a simple sheet/ridge.
Polyester is what spinnakers tend to be made from as it won’t stretch when wet (why pay £1000’s for a sail designed in 3D modeling software that looses it’s shape as soon as it’s launched).
Summary:
Nylon – tough, sight stretch, good if you want to make a ‘tent’ from your tarp.
Polyester – tough, no stretch, good if you just want a ridge tarp.
DCF – good if you want a 90g tarp rather than a 100g tarp and potentially prepared to replace it more frequently.
So it’s not a clear cut “alpkit aren’t as good because it’s heavier an Nylon”. The flipside is DCF wouldn’t be as good if you want a tarp you can fold in 3 and make a basic triangle tent when the grounds wet. Or conversely a ridge of DCF + bivi bag is heavier than a heavy weight nylon tarp and no bag. Really any company could make a lighter, cheaper tarp, you’d just be picking a different or bigger set of compromises.
