MYOG Tunnel Tent (The Frankenstein Tent: Old Materials Come Alive Again)
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Thanks Jerry. Oddly my mum couldn’t sew, but my dad could, hence why he showed me the ropes with the treadle.
And yes, Scott, treadles were amazing machines, sewing webbing and thick vinyl that would cause many a modern domestic sewing machine to cough and complain. Good at sewing fingers too, I discovered! The North Face Morning Glory had great aesthetic appeal, almost nautical in its swooping lines. As you say, a lot of fabric to content with, tho’ the individual panels themselves probably no bigger that the ‘mids that are popular today.
Thanks for your thoughts, Roger. Long been impressed with your own designs. Congratulations on those. Regarding the single windward anchor, yes, it does required this to be very secure, but I have never found that to be an issue. It does help with this design that the end of tent facing into the wind starts quite low. Less internal space, true, but also much less ‘sail area’ to be buffered. Because the tent rises gradually from ground level to a peak, wind has very little in the way of flat surfaces to push against. You enquired about deadman anchors. I have a pair of aluminium sheet snow flukes I had my dad make for me, back in 1981. They are still going strong, though I have lightened them by swapping out the original 25mm (1 inch) webbing with Lawson Glowire cord. 19cm (7.5 inches) tall x 17.5cm (7 inches) wide with a strengthing fold in the middle. 90g (3 ounces) each with clip. This year I tried some DutchWare Titanium UL Sand/Snow Anchors for side guy lines, but not yet convinced they are any improvement over long snow pegs, except maybe lighter at 30g (1 ounce). Pitching on grass I have always relied on my 8 inch (20 cm) Chouinard T-Stakes that I bought in 1985. Best tent pegs every made, in my opinion. Except I lost mine earlier this year. Until I can find some more, I have been using DAC J-stake in the longest 20cm (8 inch) length. All that being said, as redundancy, I did also add peg-out loops at the two back corners of the tent, in case I felt the need of extra security in big blow.
Thanks everyone for your supportive thoughts. It is very encouraging.
Tim, I have also used ski, poles and/or snow shovels, when windy conditions warranted some extra purchase in the snow. Congrats on having a 40 year old tent. That stills works.
And Chris, just start with smaller projects working up to more complex ones, as confidence increases.
Stephen, I tracked down a copy of the article you mentioned https://apps.dtic.mil/sti/citations/ADA279939 for a future read. Of course, your zero degrees and mine may differ. Australian alpine temperatures can drop to −23 °C (−9.4 °F) but more typically are not colder than −15 °C (5 °F).
My non-scientific experience, following a cold, still zero degree night is that the inner surface of the soft, fuzzy, non-woven Nexus lining of the Gore-Tex canopy can sometimes feel moist. But rarely to the point where it drips back on you. As the day (or tent) heats up, the moisture held in the lining layer diffuses through the Gore-Tex and the inside becomes dry again. I think it’s worth remembering that – condensation occurs when water forms into liquid from vapour. A Gore-Tex tent inner can be damp from vapour, but it is very unusual to see beaded liquid water in the canopy. Nothing like you’d experience in a typical single-skin coated nylon shelter. And not those heavy beads that fall when your condensation-laden single-skin is shaken by rain, strong winds or both. (For the record, when not extolling the virtues of tunnel tents, I am also a fan of single-skin pyramids, having used them for traverses of the French Alps, Swiss Alps, Corsican Haute Route, Pyrenees’ coast-to-coast, UK’s Pennine Way and Isle of Skye, Norway’s Rondane, Joutenheimen, Filefjell, and of course, the Aussie alps.)
From my research, it appears that Early Winters sold over 18,500 Gore-Tex tents, (models for 1 to 4 persons) over about nine years, which would suggest they performed pretty well for most users.
Todd Bibler, of Bibler Tents, made the first Gore-Tex dome tents in 1977, and later in the mid/late 80’s (when Gore exited the tent market after many US states required tents to be flame retardant) his propriety ToddTex – also a ePTFE laminate with Nexus lining. He wrote in his catalogues, “your ToddTex tent has minimal or no condensation, certainly less than any double wall tent.” Elsewhere he says, “A human body gives off 1/4 cup of water in one hour! This water must be able to dissipate through the tent walls or escape through vents to avoid condensation.” Noting, “ToddTex is breathable enough to prevent condensation.” He published test results on moisture vapour transmission rates indicating ToddTex achieved 1,210 grams/square metre/24 hours, whereas three competitor’s fabrics gave rates of 262, 643, and 876 grams/square metre/24 hours.
Marmot Mountain Works didn’t claim their tents were condensation free, rather that they condensed less. They advised, “When some inevitable dew or frost forms the highly textured Nexus liner traps it — acting as a built-in frost liner.” They advocated for the reduction of condensation via flow-through ventilation.
Wintergear, who pioneered Gore-Tex tents in the UK, and would later morph into Wild Country/Terra Nova, wrote “it isn’t a miracle fabric giving 100% condensation free performance in all condition, but to date nothing better is available.” In a later brochure they advised: ” ‘Frosting’ on the inside of the tent due to the freezing of condensation and breath in very cold conditions can also be a problem although it must be stressed that is also occurs in any tent to varying degrees no matter what its design or materials.”
The now sadly defunct Phoenix Mountaineering, of the UK, made award-winning Gore-Tex tents. They wrote “we cannot claim Gore-Tex tents to be totally condensation free they are however far and away the best form of single skin tent.” They also observed that the Nexus layer prevented drips.
In short, the Gore-Tex works most of the time, the fluffy Nexus liner greatly extends this performance and comfort range, as does low-to-high ventilation. But sometimes condensation still happens. No solution is perfect – all the time.
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