Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 22
  1. #11
    Senior Member DemostiX's Avatar
    Join Date
    Jan 2011
    Location
    Like Lewis & Clark: Wintrin' o/t Columbia again: PDX
    Hammock
    Clark w 2QZQ mod,Tropical, NX;Nano
    Tarp
    Clark micro
    Insulation
    Major down
    Suspension
    7/64 SK75 +strap
    Posts
    2,325
    Images
    13
    I am reading some quantities here that remind me of a severely DIY overstuffed quilt here that I find unpleasant. It is too much to compress, and too much to fight with in the hammock. (That said with due respect for those who willingly share twin beds with others.)

    I'd suggest you do a trial with carefully measured quantities of down and a sample chamber, such as a pillow case.

    You shouldn't start sewing without tests with your thread and fabric for tensions etc. No different with down of unknown quantity.

  2. #12
    vampiresmiley's Avatar
    Join Date
    May 2012
    Location
    Bay City, MI
    Hammock
    DIY UL w/ dynaglide whoopies (6oz)
    Tarp
    Hammock Gear Cuben
    Insulation
    Underground Quilts
    Suspension
    Whoopie Slings
    Posts
    217
    Images
    22
    Average nightly temps in the areas I camp are single digits throughout the winter, and often vary significantly below zero. Planning would depend on forecast weather (with a margin of safety). Before I start testing, I'd like to get an idea of what loft it would theoretically take to get to -20 or -25 as a bottom temp.

  3. #13
    Senior Member Orion X's Avatar
    Join Date
    May 2011
    Location
    Middle GA
    Hammock
    OXGEAR 1.1 dbl
    Tarp
    OXSHED
    Insulation
    OXGEAR 40 3/4
    Suspension
    whoopie sling's
    Posts
    106
    I ran a few more numbers for you based on my previous calculations. With a 5 inch baffle height and a 5.25 max chamber height. With 9 baffles it equals out to 3.96 oz per baffle w/ 600 fp for a total of 35.67 oz of down. That would work out to be about 5.13 inches of total loft. I come up with a temp rating of around -25 to -30 give or take a few degrees. That would be one heck of an underquilt for sure! It would be a monster . I will say that DX makes a good point about some single baffle experimentation, and testing before going all in. I know you said weight is not a major concern but a quilt of that size using 1.1 ripstop for the shell and .9 or 1oz no see um for baffles your looking at around 50 oz for the completed quit with out suspension. I say run some experiments and get a solid plan/diagram together and see what happens. In those kinds of temps you can never be too careful! If you need anything else please let me know

  4. #14
    Senior Member DemostiX's Avatar
    Join Date
    Jan 2011
    Location
    Like Lewis & Clark: Wintrin' o/t Columbia again: PDX
    Hammock
    Clark w 2QZQ mod,Tropical, NX;Nano
    Tarp
    Clark micro
    Insulation
    Major down
    Suspension
    7/64 SK75 +strap
    Posts
    2,325
    Images
    13
    When I go to see how Western Mountaineering does it for their deep cold SBs, I see two layers, which limits the variation in heat flow. Other steps to stop air leaks, too. Severe temps are associated with wind, and convection currents matter a lot more.

    Even if this were not going to be heavy, fit matters more than it does at higher temps. I wonder if more attention needs to be paid to controlling air and water vapor with fabric selection, as against brute force of lots of down.

  5. #15
    Senior Member Orion X's Avatar
    Join Date
    May 2011
    Location
    Middle GA
    Hammock
    OXGEAR 1.1 dbl
    Tarp
    OXSHED
    Insulation
    OXGEAR 40 3/4
    Suspension
    whoopie sling's
    Posts
    106
    I completely agree with fit being very important to the effectiveness of the quilt as well as fabric selection. With that much heat being generated there would be moisture accumulation for sure. The use of a wind block on the head and foot end would be a must to prevent heat escape and cold seeping in. I have never had the need to make a quilt for that temp range. I also wonder if making a double layer of baffles that were slightly offset would be effective..but then that would be up to the OP and there sewing skills. Yall have me intrigued to the point of wanting to make one just to see if it would work. I also wonder if there is a certain point where the amount of loft that is wanted becomes unobtainable via traditional baffle construction...hmm something to look into.

  6. #16
    vampiresmiley's Avatar
    Join Date
    May 2012
    Location
    Bay City, MI
    Hammock
    DIY UL w/ dynaglide whoopies (6oz)
    Tarp
    Hammock Gear Cuben
    Insulation
    Underground Quilts
    Suspension
    Whoopie Slings
    Posts
    217
    Images
    22
    I am also constructing a canvas sock, to help with the wind while maintaining breathability. I'm currently testing various designs, though the weather has only been in the mid to upper 30s so far. I had also planned on adding draft collars at the head and foot ends to help prevent air leaks. I was considering a double offset baffle, but was unsure how much benefit it would gain over the the standard baffling.

    I'm interested in your thoughts on managing vapor permeability of the UQ/TQ with material selection. My initial thought was to use a vapor barrier liner to help prevent condensation in the down. The liner would also allow me to potentially pair its use with other quilt sets. Do you see additional benefit in using coated materials in part of quilt construction?

  7. #17
    Senior Member DemostiX's Avatar
    Join Date
    Jan 2011
    Location
    Like Lewis & Clark: Wintrin' o/t Columbia again: PDX
    Hammock
    Clark w 2QZQ mod,Tropical, NX;Nano
    Tarp
    Clark micro
    Insulation
    Major down
    Suspension
    7/64 SK75 +strap
    Posts
    2,325
    Images
    13
    Because you are thinking "special purpose", consider custom design for your hammock.

    Draft stoppers and collars may be inefficient use of materials. Traditionally, on SBs, they fill and insulate a space along zippers, or are smaller-circumference collars, applied full length. In contrast, when used at the ends of hammock UQs they are expected to be scrunched, stuffed like backing for caulk to fill furrows.

    I'd suggest instead a short trapezoidal skirt of low permeability fabric sewn to the end and up the side seams of the UQ, just long enough so the inner hem overlaps and encloses the last few inches of the UQ. That hem has a channel and is threaded with a light shock cord and a cord lock. Total weight for both skirts, head and foot ends? An ounce?

    The full length UQ gets mounted and the skirt hem gets pulled just snug against the loft. The seal here,of a few inches of skirt overlapping a few inches of UQ is excellent, with the minimal compliance of the U. Air passing up and down the furrows beneath the UQ, such as when feet shift and those furrows re-form inside the hammock, cannot escape the skirt because the skirt is sewn on three sides, and cinched on the fourth. Airr cannot get in from the outside either.

  8. #18
    vampiresmiley's Avatar
    Join Date
    May 2012
    Location
    Bay City, MI
    Hammock
    DIY UL w/ dynaglide whoopies (6oz)
    Tarp
    Hammock Gear Cuben
    Insulation
    Underground Quilts
    Suspension
    Whoopie Slings
    Posts
    217
    Images
    22
    Wow, I like that line of thought. Basically a hammock custom fit for the UQ to address the heat seal, rather than trying to modify the UQ fit to seal to the hammock in extreme conditions. With materials for the hammock generally being a fraction of the cost of the UQ, that is a really interesting suggestion.

    What started as a relatively rudimentary project may just turn into something much more interesting...

  9. #19
    Senior Member Orion X's Avatar
    Join Date
    May 2011
    Location
    Middle GA
    Hammock
    OXGEAR 1.1 dbl
    Tarp
    OXSHED
    Insulation
    OXGEAR 40 3/4
    Suspension
    whoopie sling's
    Posts
    106
    I as well really like that thought, and it gets the gear making juices flowing for sure! Its amazing how a simple question can take us down the proverbial rabbit hole. DX thank you for your gracious input and OP I hope you haven't been dragged in over your head...or at least to deep anyways

  10. #20
    Senior Member DemostiX's Avatar
    Join Date
    Jan 2011
    Location
    Like Lewis & Clark: Wintrin' o/t Columbia again: PDX
    Hammock
    Clark w 2QZQ mod,Tropical, NX;Nano
    Tarp
    Clark micro
    Insulation
    Major down
    Suspension
    7/64 SK75 +strap
    Posts
    2,325
    Images
    13
    Quote Originally Posted by vampiresmiley View Post
    Wow, I like that line of thought. Basically a hammock custom fit for the UQ to address the heat seal, rather than trying to modify the UQ fit to seal to the hammock in extreme conditions. With materials for the hammock generally being a fraction of the cost of the UQ, that is a really interesting suggestion.

    What started as a relatively rudimentary project may just turn into something much more interesting...
    Every time I get into a Clark hammock, I see the stitching across the bed of the hammock. The company is still in business, and still stitching those pockets.

    So, I suggest to you that this can be easily tried with just about any hammock

    You can even keep all of the stitching in the side hems on the sides and within the channel, if you insist on not putting any stitches across the bed of the hammock, That will make the skirts longer than necessary. Assuming a 10 ft hammock an 80" UQ, and 5" over overlap/ adjustability, it is a 2' swath of fabric for each skirt.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •