Part 1: Plans
The Concept
A differential cut 50” x 38” underquilt with 7 vertical baffles, and a 2”-2.5” loft (something like 20F). A very simple suspension run through channels on the long sides, and cinches at the head and foot. Aiming for less than 14 ounces, really hoping for ~12 for the quilt + suspension.
Me
This is my first MYOG project, and I have no particular skill with sewing. One of my best friends is a professional seamster, though, and has offered to let me use his sewing machine and oversee my work, so I’m not at all worried about screwing it up too badly.
Some math
To reach the cut numbers list below I did the following:
- Inside fabric length = UQ base length (50”) + seam allowances (2 * 0.5”) = 51”
- Inside fabric width = UQ base width (38”) + seam allowances (2 * 0.5”) = 39”
- Outside fabric length = UQ base length (50”) + seam allowances (2 * 0.5”) + channels (2 * 0.5”) + total baffle height (2 * 2”) = 56”
- Outside fabric width = UQ base width (38”) + seam allowances (2 * 0.5”) + channels (2 * 0.5”) + total baffle height (2 * 2”) + magic result of trigonometric calculation from differential calculator spreadsheet (3 15/16” [nearly 4”]) = ~49”
- Baffles length = UQ base length (50”) + seam allowances (2 * 0.5”) = 51”
- Baffles height = UQ base loft height (2”) + seam allowances (2 * 0.25”) = 2.5”
- Suspension length = Length of hammock to end of continuous loop (2 * ~11’) = ~22’
- Cinch cord width = UQ base width (38”) = 38”
Cut/prepare pieces
Outside fabrics - 56” x 49” - Ripstop
Inside fabric - 51” x 39” - Membrane 10
Baffles - 6 * 2.5” x 51” - Noseeum
Suspension - ~22’ - Lash It
Cinch cord - 2 * 38” - shock cord
Shopping List
2 yards of 1.1 oz calendared ripstop nylon ($10.80)
2 yards of 0.66 oz Membrane 10 taffeta nylon ($19.90)
1 yard of 0.5 oz NS50 noseeum mesh ($6.75)
7 ounces of 850 FP goose down ($61.25)
Grey Polyester Thread ($1.99)
25 ft of Lash It 1.75mm ($5.50)
25 ft of 3/32 shock cord ($4.25)
4 Double cord locks ($1.00)
2 Ti Dutch Hooks ($5.00)
Total is somewhere around $130 give or take for shipping/taxes.
Some explanations
- All four sides will have quarter inch channels made of the outer fabric.
- The head and foot are for cinches, and will have cord locks attached on either side, and shock cord running through the channel and both cord locks and tied on either side.
- The sides will simply have one long (~22’) piece of Lash It that goes down one side and up the other, and then is tied off-center. This way I can add or remove tension by tying the knot looser or tighter. The whole suspension will be attached to the hammock suspension using the Ti Dutch Hooks
- Some of this is based off of this reddit post. I was a little worried about the size, but I contacted that person directly and they assured me that size was good for them on an AT through-hike. In particular I asked about the 38” width, but they said their shoulders were never cold, so I trust that. I plan on using a stuff-sack as pillow, and my backpack under my feet/calves.
- The math just works out so that each baffle takes 1 oz of down. Convenient, with the individually bagged Wilderness Logic 1 oz down bags.
- There are slightly lighter materials for the outside fabric, but I deemed it not worth the fractions of an ounce given the downproof, durable and water resistant choice of plain-old calendared ripstop.
- When I get to sewing on the baffles, I’m not going to worry too much about knowing ahead of time where to place them, I’m just going to measure for the seams and channels, and then evenly divide whatever is left on inside and outside (after baffle height on the outside).
- Saw the trapezoidal approach… I’m not going to worry about that for now.
- Vertical baffles because I’d rather set the down and forget it, than worry about karo step or anything. My feelings on this are very mild.
- I have a plan hopefully might make putting down into the baffles simpler/cleaner. I want to try to cut the 1 oz down bag over, shove it inside the baffle opening first, then hold it in place and try to beat or prod the down out in its compressed state so that I might avoid getting any of it airborn. We’ll see if that actually works out.
- This will be for a couple of hikes in the Sierra this summer, and probably some Oregon/Washington PCT sections next summer.
- Planning on pairing this UQ with an Enlightened Equipment Enigma 20F overquilt, a Dutch Halfwit hammock and a TBD MYOG hex tarp. Aiming for a total sleep system under 3.5 lbs (under, over, hammock, net, tarp, lines and stakes).
Questions
- First of all, does all of that check out?
- Will the channels made of ripstop be durable enough?
- Does a simplified, purpose cut, single-piece suspension system make sense?
- Does the cinch system make obvious sense there?
- Any other advice about this before I make the dive and purchase the materials?
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