Wow. I spent a long time thinking, planning, avoiding, procrastinating, thinking, forgetting, and finally finishing my new 3/4 length, 4 inch, differential, down underquilt. I hope to use this quilt winter camping.
I think I think I started asking the forum questions about a year ago. I finished the quilt a day or two ago.
Finished Width ~43"
Finished Length ~53"
Weight 1.48 pounds (0.671 kg or 23.67 oz) including suspension
Color: black DWR nylon (not ripstop) from the $1 bin at Walmart. I have no idea what it is, but I can puddle water on it without its seeping through and I can barely suck air through it so I think it is somewhat breathable.
Suspension: side channel bungie
Down: 12.7 oz of 900 fill Speer down (I actually fudged and considered it 850 only and then overstuffed to 20% on top of that)
Fabric width 45" (42" +2*1.5" per side for seam allowance)
Fabric length 55" (52" +2*1.5" per side for seam allowance)
Baffle width 6"
2" pleats tapering to zero, four inches from the center
Fabric width 57.5" (49" +2*1.5" per side for seam allowance + 2.75"*2 for the side chanels)
Fabric length 61" (52" +2*1.5" per side for seam allowance + 2*3" for the end walls)
Baffle with 7"
2" pleats tapering to zero, four inches from the center.
The outer baffles include an extra 2.75" to account for the end walls. I would have made them larger, but I was constrained by my fabric width.
After sewing the pleats, the two shells were folded in half and laid side by side for comparison. The inner shell (left) is much smaller than the outer shell (right) and both are narrowed by the pleats.
I sewed the mesh baffles to the outer shell first and then to the inner shell. Closing the ends turned out to be harder than I had expected and this is where I noticed my first mistake. I had intended to roll the edges to make a small channel and avoid having to use grosgrain edging. The problem is that when you gather the outer, large shell to match the shorter, inner shell, you have to pleat it again. Gathering the fabric together left a very messy edge and i did not have enough fabric in my 1.5" seam allowance to gather it all together neatly. So, I cut off most of my edge to about 0.5" and used grosgrain.
And here was my second mistake. I decided to use contrasting color thread to make inspecting the thread for wear easier. Hmm. I may wish to take up drinking. Perhaps my seams will go straight after that.
I gave up on the white thread and I got better by my fourth edge . . .
When it was all done, I couldn't believe how puffy it was and I started to have some serious misgivings about how much down I had put in there. It remains to be seen if I added weight for no real temperature rating improvement.
I put it on my Hennessy and although I haven't had any really cold weather yet, I was able to sit in shorts and a T-shirt in 55 weather with no top cover and be quite comfortable from the heat coming up from below.
Like StormCrow's design, this has ends which gap a bit and can be cinched up to the hammock. Here is a view before closing up the ends to show the loft
I am quite pleased with the results although I wonder if there isn't a better system for creating the bathtub shape. I choose a symmetric design which may not be optimal but it did make my life a bit easier.
All in all, I estimate that I spent 20 hours cutting, sewing, seam ripping, sewing again, and stuffing. I am very slow! Perhaps the next one will be faster
Thanks again for all the help (all of you on the forums, but especially Dalton, Te-Wa, and StormCrow) and for reading this far along. Bring on the snow!