MYOG - cuben shelter

Discussion in 'DIY & MYOG' started by cathyjc, Feb 16, 2015.

  1. WilliamC

    WilliamC Thru Hiker

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  2. cathyjc

    cathyjc Thru Hiker

    Just seen his photo.
    The damage on mine is much smaller - pinpricks (sometimes lines of pinpricks) - compared to that on @maddogs . I might not have noticed those on mine if I hadn't been looking up and seeing pin pricks of light shining down.
    But there is a similarity in that the Dyneema fibers are still there whilst the Mylar holding them together has "gone"
    maddogs likes this.
  3. maddogs

    maddogs Trail Blazer

    Interesting! Did you come up with a repair?
  4. WilliamC

    WilliamC Thru Hiker

    Cuben/DCF can suffer from creep when under tension. I wonder if in both your cases the mylar/PET film reached the limits of its elasticity?
    The 0.8oz DCF is supposed to have a "better" PET film than the 0.51 and 0.74oz stuff but I don't know in which way it's better.
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  5. cathyjc

    cathyjc Thru Hiker

    I've put some 'patches' over the most obvious areas at the top of the tent. There is plenty of life left in it ATM and some moisture ingress isn't going to matter as the amount of likely condensation will "drown it out" :whistling:. I'm putting it down to 'wear and tear'.

    Lessons learnt :-

    a) 26g/0.8oz is probably more suitable than lighter weights. I'm guessing it would add about 70gs extra to the weight of my shelter - I can live with that.

    b) The gradient between weight of main fabric and the reinforcements (tie-outs/zip/cone) needs to be gradual - less of "a jump". I now think the area of any reinforcements needs to be greater and the fabric used closer to the main fabric in weight - to even out tension across the greatest possible area rather then focusing it in a few small areas.

    That's what I plan for any new shelter.
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  6. maddogs

    maddogs Trail Blazer

    Agree on wear and tear, it's just a trade off of cuben vs other material... the tent is currently at $4.66 per night which seems pretty reasonabke. If we can repair it and get another thru hike from it I think it would be outstanding.

    The gradient thing sounds very logical and the corner tensiiners on my groundsheet certainly support that.

    Here's the cuben stuffsac. I think it's a lighter weight than the grey groundsheet, same stuff as the fly, but clearly where its grabbed and pulled around the opening, the stitches seem to open up the fabric here too. I guess a hand holding and pulling is equivalent to an attachment to a heavier fabric.
    The second line of detachment (left most in this photo) is intriguing...?

    Bottom line I suspect is that taping/gluing seams might be better? Stitches seem to generate a weakness.

    [​IMG]
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  7. cathyjc

    cathyjc Thru Hiker

    Stuff sack - my stuff sack feels/looks more worn than the main fly on the shelter - OI agree it gets much more abrasion and "tussle".
    I agree and have said before that sewing/stitching isn't great on DCF. I'd recommend avoiding it as much as possible.

    It's interesting that the bonded seams on my shelter will be 'good' long after the rest of it is worn out. I'd question the need to stitch, then tape seams for strength - my experience suggests the fabric will fail long before the bonding - and stitching first is not essential. I know Colin Ibbotson will argue otherwise :whistling:
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  8. Enzo

    Enzo Thru Hiker

    My take is bond 0.51, heavier can be stitched and taped.
    Presumably the strength of bonded seams is constant whatever the weight of cuben, whereas the strength of stitched seams goes up dramatically with uhmwpe content so at some point the lines on the graph will cross.
  9. Lempo

    Lempo Thru Hiker

  10. Rog Tallbloke

    Rog Tallbloke Thru Hiker

    @Lempo I think the obvious solution to this problem for UK users is to avoid taking their cuben tent on the once in a decade occasion when temperatures at 2000 feet reach 0F (-16C). If you're dead set on camping on Ben Nevis summit in winter, take a tough piece of nylon (and a bottle of whisky).

    I think 0.51 cuben is an amazing innovation, enabling ultralighters to trim a pound off their packweight in 3 seasons.
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  11. cathyjc

    cathyjc Thru Hiker

    You just ain't going to find me out camping at 0F (-17.78C) :wideyed: - my sleeping bag won't go that low for starters.

    But for those that do then take note !
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  12. Rog Tallbloke

    Rog Tallbloke Thru Hiker

    That's where the whisky comes in handy. Heavy to carry up, empty to carry down.
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  13. maddogs

    maddogs Trail Blazer

    done it once. never again!
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  14. maddogs

    maddogs Trail Blazer

    Are the tapes being talked about here double-sided? The only ones I've seen have been for seam sealing.
  15. cathyjc

    cathyjc Thru Hiker

    The glue for bonding is held on a carrier tape. Like Selotape but you peel the surface layer off and have the glue left to stick your other layer of DCF to it.
  16. maddogs

    maddogs Trail Blazer

    So do you overlap the two panels to be bonded, or just butt them up against each other and tape over?
    I'd imagined if there was a double-sided tape it would be sandwiched by the overlapping pieces.
    (sorry I'm sure I'm being very dense here!)
  17. cathyjc

    cathyjc Thru Hiker

    Overlap.
    The glued bond is stronger in 'shear' than in 'peel' - so butting against each other wouldn't really work very well.
    maddogs likes this.
  18. Enzo

    Enzo Thru Hiker

    I think the stuff Paul sells is glue both sides of a carrier, but the twice as expensive 3m stuff I think is just a layer of glue between non stick paper?
  19. cathyjc

    cathyjc Thru Hiker

    I've used the 3M stuff - it is as you say ^^^.
    What @paul is selling ATM - you'd have to ask him ??
  20. Enzo

    Enzo Thru Hiker

    I've used both and unless I'm not remembering well (wouldn't be the first time!) I think that's correct. I guess Pauls stuff might end up a fraction heavier.
  21. Lempo

    Lempo Thru Hiker

  22. WilliamC

    WilliamC Thru Hiker

    I'm a little confused by this. Does CT1E.08/K.18 mean that it uses a different type of PET film on each side, one 0.08mm thick and the other 0.18mm thick?
  23. Rog Tallbloke

    Rog Tallbloke Thru Hiker

    I'm guessing the K.18 side is the printable film.
  24. WilliamC

    WilliamC Thru Hiker

    K is, I think, mylar film while E is a different PET film which is supposed to have better durability. But I can't cite references :sorry:
  25. Lempo

    Lempo Thru Hiker

    Last edited: Oct 31, 2020
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