After reading everyone's comments, I was not convinced that an all cuben dome or tunnel tent could not be made; thus eliminating the need for nylon panels. The GG One is mostly spinaker, which has very little stretch, but many satisfied users. But for a dome or tunnel, any pattern available would probably be intended for a nylon tent, as the bias stretch on the nylon should affect how one shapes the panels. I believe that working with no-stretch fabrics on geodesic or tunnel shapes will require a new technology or at least a very new approach, that, to borrow from T. Edison, will involve 1% inspiration and 99% perspiration. Go for it. But it won't be I, because the designs I'm working on depend on the diagonal stretch in nylon fabrics, on decent quality silnylon being quite sturdy for its weight, and on its affordability. I also worry about puncture resistance in the mylar that holds the cuben fibers together. So, will use cuben for door covers under an awning for a start. If they don't work out, they can be fairly easily replaced.
Jack Stephenson once told me that coated inner and outer walls on a double wall tent will be just as, if not more effective than a breathable inner to prevent condensation, and then provided his aerospace engineer's scientific explanation. He also mentioned that if the inner cannot get saturated with condensation, you don't have to carry the weight of the water in your pack. If this is all or mostly true, then the extremely light weight and vapor impermeability of cuben might be a workable double wall approach, especially for a tunnel, where you don't have to fool with crossing poles. That Early Winters tunnel tent I mentioned before was called the "Omnipotent," and although I never met one in person, and although it was a double wall, the photos nevertheless do suggest that there was a seam parallel to the pole hoops and halfway between them that created the catenary cut for a taut pitch. If this could be done with Cuben, maybe that's an answer.
Miguel; Thank you for the link to the Suolo pitch. It appeared that the whole tent went up without exposing the inner tent or floor to the elements. Although, at the risk of using the term, "Walmart," it was not clear to me how protected the very top of the roof was before the small Walmart type patch fly was affixed to the top. These little flies have been used on cheap domes for ages, but in a trekking tent, should have zip up panels with protective netting underneath, with the zips protected by flaps, to keep rain out during the pitch. The effect also allows top vents to be opened and closed from within the tent once the little fly is securely affixed over the top.
Roger, I don't want to get into politics here, and feel that each tent should be evaluated on its own individual merits, but agree that the Nippen tent is inferior, in the sense that the bathtub floor of a wedge dome of this type is going to fill up as soon as the door is opened for entry, if not during the pitch also. Will never forget my one nightmare experience with this when it was "raining buckets." It's a good thing that Shelties cannot file for divorce from their owners. The Suolo dome appears far superior in this department, and also has lots of vestibule storage space integral to the tent design, not some kind of add-on. But it's way too heavy for my target of 2#. In any event, the makers often advise to stake the corners of wedge domes first, before installing and clipping the fabric up to the poles. But no question, Roger; that is still not going to be anywhere near as effective in helping one get the tent up in a blow as with your double wall design with exterior pole sleeves.
Still think that rain blowing at an angle into the gutters along those exterior pole sleeves is more likely to find its way in than if the poles were inside a clean canopy. Noted that your "When things go wrong" tent is a double wall (beautifully crafted BTW). If there is an inner tent with a DWR coating, minor leaks in the outer due to extreme conditions may well run off the inner to the ground. But if single wall design is the only way to get to really light weight, then the inegrity of the one wall becomes more critical. A pin hole in a deluge could spell disaster, which may explain some of the accounts along these lines on this web site in discussions of single walls.
Happy Holidays, everyone. Am finishing up some tests on carbon and carbon/FG shafts, as well as flammability and porosity of some different silnylons, will post some results on the MYOG forum and then begin another marathon tent project.
Sam Farrington
