Dyneema for a partial ground cloth??

I don’t know how rough you would be on the material, Eric, but here’s something I have done. I got tired of having to sit on a wet log when taking a rest break or snagging some lunch. I made a 18″ x 15″ cuben piece that I could unfold and lay on a rock or log to keep my butt dry (I carry one of these when snowshoeing for the same use). I used 1.43 g/sq. meter cuben (or Dyneema, if you like). I’ve also used one of these to set next to my pack to keep stuff from sitting in the dirt when unpacking things. I routinely place one outside the tent’s door to set my boots on at night. These uses aren’t really causing significant wear from abrasion, which is of course cuben’s main weakness. I’m rather sure that a less burly cuben weight would not hold up as well as the 1.43.

Gary,

I am not worried if the Dyneema gets some small punctures over time as I mainly want it to prevent wear and for a relatively dry space the vestibules to keep mud and other debris out of the tent. Maybe the weight savings with something that small may not be worth the price v.s. silnylon “heelprint”.

I’d say DCF is the wrong material for this job.

The positive properties of the material are extremely high tensile strength for the weight, and high HH.  The negatives are poor puncture and abrasion resistance and price.

This application has no need for tensile strength, and is primarily subject to puncture and abrasion.

Have you considered any of the Membrane fabrics at RSBTR?

Why not polycryo or painters tarp material?

Or give the 2x thick polycro sold as window sealing kits a look.  I’ve used a 2 oz DIY groundsheet made from this for over 4 years with no discernible wear.

I’m using kite tyvek. Nice because I can throw it in the wash.

Those SOL emergency blankets work well and do not stick to snow.

Why post this in the SUL forum?

what Rene said – properties of dyneema good for packs or guylines, not for a ground cloth, lightest weight nylon good to protect bottom of tent from punctures

People keep talking about polycro so I tried it.  I just happened to have a window kit in the garage, not being used.  That works pretty good although it’s slippery.  I wonder what would happen if it got frozen to ground

I’ve tried Tyvek but it’s not waterproof and a bit heavy.  Good for protecting bottom.  I wonder if it would freeze to ground.  I put silicone:mineral spirits on a piece for car camping.  That works really good, but probably too heavy for backpacking.  Again, I just happened to have some leftover from a house project.

Yeah, DCF/Dyneema is likely the wrong stuff. It has little abrasion resistance though high strength. A somewhat heavier grade of nylon, say 1.9oz cloth, might work well. It has good abrasion resistance, good strength, good coating and good weight. Likely the best all around fabric with good durability, but a 2-2.5yd piece will weigh between 4-6 ounces. If you are looking for a good balance between weight and durability, the very light nylons (7D,) heavily coated will drop the weights to around 3oz. Super light weights are best found with a plastic film and weigh 2ounces or less.  This assumes a 3’x6′ piece or 2yd.

Plastic painters films work well but are prone to punctures and should be considered disposable after a couple uses to a couple weeks depending (thickness & terrain.) Polycro will last about 4-6 weeks. Sil fabrics (0.9oz/1.1oz) work well but the factory coatings are often too thin, but they can be re-coated. Caveat: the weight starts looking like a heavier fabric. DCF is like plastic films, except it has some spectra reinforcing threads for strength, it can not be re-coated easily. Laminated DCF is just very heavy. Poly has less strength and less abrasion resistance than nylon, but is cheaper and some types can be re-coated. Tyvec works and weighs about the same as nylon, but doesn’t pack as small and picks up dirt/small twigs/needles/etc easily.    …A quick overview from my experiences with these.

People keep talking about polycro so I tried it.  I just happened to have a window kit in the garage, not being used.  That works pretty good although it’s slippery.  I wonder what would happen if it got frozen to ground

Yes, polycro is rather slippery.  I taped a small nylon washer into each corner of my DIY 1.5 MIL polycro groundsheet, and run a very light guy line out to the 4 tent corner stakes.  Obviously this doesn’t diminish the slipperiness, but it does keep everything in place.

I can’t comment on whether/how it freezes to the ground as I’ve never camped on snow.

Tyvek, young man :)

I would recommend Tyvek.  But I also must echo Ken’s sentiments and ask what this has to do with SUL.  Groundcloth?  What the hell is a groundcloth?!?  When I’m going out SUL I expel all the energy saved from carrying less gear into my mind and harness that to levitate off the ground while sleeping.

Levitation, of course, why didn’tI think of that? Haraldson you clever old Viking!

Tried Tyvek. Hate why way it collects crap. Painter’s plastic works so far for a vestibule floor and is cheap. I only take it when I’m sure there will be multiple days of rain. I have been known to cut a few evergreen boughs for a vestibule “floor”, mainly in winter. LNT? Well, I did scatter the boughs on breaking camp – so there.