I just bought a used North Face 15+ down bag on ebay. It is 76longx31shouldersx16feet on measurements.
Here is what I want to do; think it will work?
I want to make a insulation buffer for my now "Fall/Spring" underquilt. I am happy with the DIY underquilt I have made, but in winter at about 40 I start to not get a relaxed nights sleep because I wake up and have to shuffle around to keep spots warm. My cold spots are as others have, any pressure spots on the hammock. Hip, shoulder, knee. The cold spots get worse of course the colder it gets. I am not getting wind, just my UQ is not keeping my "fluff" warm. I want a "layer" UQ so I can put it in or take it out (between my hammock and my now UQ) with velcro when I need it on 35ish degree nights or lower. Texas does not see too many of these.
So, with this down bag, I want to take out the zipper and continue from the end of the zipper all the way down and out the bottom of the bag. Basically cutting the bag so that I have a big flat down bag.
62" x 32" triangulated rectangle is what I think I will get when flat. Does this sound right?
Now here is the question. If I make a quilt, 32" wide and 76" long I will have a twotriangle pieces left over off the 62" shoulder area down to 0" at the bottom of the bag. So, I will have two triangles of 15" inches to 0". If I take the 0" and sew to the 15" and the 15" to the 0" I will make a 15" by 70"ish rectangle. Where would this new "trim" triangle be best served?
Adding to the 32" width giving me higher sides on my underquilt, or sewn corner to corner of my 32" x 72" quilt to give me more loft laying at my angle in the BlackBird, or fold the 70" in half giving me a 35" by 15" piece that I can use as added loft under my butt/back area on the down quilt? Meaning I would have a single layer down from head to toe and a triple layer down on legs, back shoulder area. Again, remembering that I have a UQ now that fits the BB perfect, but my insulation only takes me down to about 40. I am trying to get a full length down "add-on" for below 40 degree nights.