I am working on an under quilt for a custom asym hammock I just finished making.  I’m kind of new to this.  I’ve read that air gaps between the quilt and the hammock will result in cold spots, which sounds bad.  However, in experimenting I’m finding it particularly difficult to come up with a shape the will hug the hammock everywhere.

A lot of designs I see (KAQ for instance) seem like they cannot possibly be eliminating all gaps.

How critical is this and are there some tricks (shaping or design) that might help me?

Darts can be cut around the edges of an under quilt to make it curve to the shape of the hammock.

You may consider several triangular cut-outs 1” wide, and 5” deep, about every 12” along the long length of the quilt, and, four darts of 1” wide and 3” deep accross the ends. The more darts, (and,or deeper) the more curved it will be. The finished length and width diamensions will need to be adjusted to compensate for this shortening caused by the darts. The darts will cause the finished quilt to “cup” around the hammock when attached, thus fitting tighter than a “flat” configuration. Sizing the outer piece of fabric, larger than the inner, (the baffel width bigger, say for example 2.5” x2 = 5”) allows for proper loft ie. a differiental cut. This can be done by laying the inner piece over the outer piece and marking them both for darts and baffels so that they are in the corresponding place top and bottom when sewn together. The bigger “differential” piece will of course be hanging down.  I use karo baffels, instead of “tubes” for the down filling, because the down can all be easily dumped in, without weighing, the quilt sewn up, and the down shaken around to equalize it’s distribution. It stays put nicely, and, I can move the down around where I want it, depending on temperature. By using my Hennessy SS foam pad, as a pattern, I could also exactly place the diagonal tie-out points accross the bottom, to help hold the quilt up even better.

Making an experimental sheet with cheap fabric, and seeing how it fits is recomended. I have yet to see any plans for these darts with measurements, only rough diagrams. But, it is not difficult to imagine. There are probably other better ways. I don’t have any pictures as of now.

Thanks for the input.  I have been working with a sheet of fabric as a prototype.  I’m using Climashield insulation, not down, for this project.  A down version may well be in my future but I thought starting with something easier to work with might be wise.  I’m guessing differential cut is less of an issue with synthetic but a was think about using it.  That way I could pull the inside tight without compressing the insulation at all, that would have to help.

What I did was put clothes pins at 1ft intervals on my hammock, both sides and down the center.  Then I hung it and took girth measurements along the lines marked by the pins.  From these I made a rectangular pattern with four fairly substantial darts, two on each end.  I thought working from the ends would mimic the hammock body best.  I pinned it up (didn’t cut so I could try again). Overall I was pretty pleased with way this worked out, the shaping is very close and think with the appropriate tweaks it will work.  The fabric doesn’t hang quite where I measured, especially on the ends where there are some pretty good gaps.  There’s also a problem spot to one side of my legs.  It’s pretty good elsewhere.

I’m making the pattern from an empty hammock and getting in loads it differently.  I think my pattern will be flatter this way that it will be when I’m in it and I will need some adjustment in the suspension to wrap it around a bit more.  Thats should make it conform to changes in sleeping position better than a super fitted one would.  A KAQ, is certainly flatter than an occupied hammock and from all reports they seem to work well.  Does this make sense?

Yes, that’s about it. Sounds like you have it. My first quilt was down, I considered synthetic out of apprehension about the challenges of working with down, but, it was not a problem, filled things outside, and there was no mess. Only lost a few fluffs here and there.

Thanks again.  I’m gonna stick with the Climashield for this one.  Just curious, how did you manage with the down outside?  I’ve read that any little breeze is trouble…