DIY- UQ- will a tapered shape work as well as rectangle?

[BackpackerGuy]

I scored another Ozark Trail 32*F down sleeping bag from WalMart yesterday for $30.00.
I already have one, which I've converted to a nice TQ.
(Another thread touts the efficiency rating of the bag when used as a TQ, and I can verify it is very warm at 39*F.)

I plan to mod this new bag into an UQ, probably a full-length.

My question is this:
If I make mine tapered - I'm thinking 10" narrower at the bottom than at the top - am I setting myself up for any unique challenges in terms of hanging it effectively, or how it will conform to the bottom of my WB BB hammock?
Thoughts? Suggestions?

I know most cottage vendor / DIY plans show a rectangular shape UQ.
Any logical reason it can't be made tapered?

Thanks

[WV]

Tapering shouldn't present challenges as severe as the ones you'll have already - making a flat quilt fit the curved undersurface of a hammock and stay in the right place. If you're not daunted by cutting into a down bag, why not put a couple of darts in each side of your tapered UQ plus one dart in each end, as some UQ manufacturers do?

[BackpackerGuy]

WV - thanks for the input.

Tell me more - if my UQ will be, say, 70" long, 52" wide at the top, 42" wide at the bottom, how many darts might I need on each side?
On each end?
How long would each dart need to be?

Tapering shouldn't present challenges as severe as the ones you'll have already - making a flat quilt fit the curved undersurface of a hammock and stay in the right place. If you're not daunted by cutting into a down bag, why not put a couple of darts in each side of your tapered UQ plus one dart in each end, as some UQ manufacturers do?

[BackpackerGuy]

Any more suggestions?

[boulderv7]

My suggestion would be to salvage the down out of that bag and put it into a newly sewn UQ shell. This is a whole other beast though. If you don't have a differential cut in an uq, it will not function as well, due to compression of the down when under you. The challenge, as WV pointed out, I'd making a flat quilt conform to the curved surface of the hammock with a body in it. This means that the inner layer of the uq needs to be shorter and less wide than the outer shell to allow the outer shell to drape down and allow room for the down to loft. The number of darts needed would be entirely up to you. I would recommend looking at one of the UQ calculators on this site and get a rough estimate of the amount of differential needed for the loft you hope to attain. That would give you at least an idea of what measurements you should be aiming for in terms of inner and outer layers. I hope that's clear.

[brodieb666]

you could probably start (once you have the bag opened up) by simply pinching the edges together and putting in a stitch from the outside through the pinched layers to mimic a dart, and place a few of these on each side to get the curved form.
If you want to get a little more complex take two pieces of the inner quilt layer and pinch them together and then stitch just through those inner layers. Make a few of these down each side and you will not only mimic darts, but have the inner layer tighter than the outer so you won't get any compression.

And then post pics and comments so i can benefit from your efforts without screwing up the ozark i buy