Sew through on Under Quilt

**traftonm** · 08-24-2011, 18:11

I'm going to do a under quilt for worm weather. Question is this. When doing sew through costruction do you leave som slack on the under side? I was thinking 42 inches for the side that is agenst the hammock. 45 inches for the side that will hang. This will give me 1/2 inchof slack. I'm going to use 6 oz of down, the shell should be about 3 oz using Momentum 55. Hoping to use it to about 35* Any advice would be great.

**hangnout** · 08-24-2011, 18:27

Probably not enough of a diff cut for a sewn thru. Remember that the outer layer will be a bunch of "U's" that will require more material across the width than a baffle style UQ.

**traftonm** · 08-24-2011, 18:34

Any idea how much more material for the side that the u is on?

**hangnout** · 08-24-2011, 18:50

Without doing any math I would think you would need to add 1.5 -2" for every chamber to make sure you have the loft to get to 35*. Assuming that you are going to make seven 6" wide chambers you may need to go as wide as 56" to ensure around 1.5" of loft in the center of each chamber.

Try cutting some strips of paper starting with about 8" long. Put each end of the strip on a ruler at the 0 and 6" marks and see what the curve gets you. When you find a length you feel will work, multiply by 7 and that will be the width you need plus hem allowance

This pic from Dutch's gallery shows a good example of how to mock up the quilt before starting to sew. Went way back to 2008 to find this one

**hangnout** · 08-24-2011, 19:00

BTW I assumed we were talking about the width of UQ not the length?

**MAD777** · 08-24-2011, 19:27

I sewed one of those! It's filled with 3oz of 900 Fill Power down from Ed Speer.

I made each chamber a semi-circle. So, what ever spacing you use on the hammock side, multiply that by pi/2 to get the spacing on the outer side.

The average thickness is going to be a function of the inner spacing. So, let "S" be the inner spacing....

pi * S / 8

Here are some pictures of mine...

**Strung out** · 08-24-2011, 20:01

Good stuff from everyone so far.

If you want to state your planned length of the quilt (assuming it will be rectangular) as well as the fill power of the down you plan to use, we can give you a much more precise answer.

BTW, I made a sewn through recently with 6oz of 800+ fill and I was good to 37 degrees F last week.

My quilt was made with baffles at 5" (inner shell) and just over 6" of spacing on the outer shell for each one. This leaves me with about 1.5" of loft.

**traftonm** · 08-24-2011, 20:28

I'm going to make it 42 inchea wide x 68 inchea long. 6 oz of 800 fill down. 6 baffles running long ways. 1 oz of down in each. spacing will be 7 inches.

**Strung out** · 08-24-2011, 21:05

If you make the outer shell 8.875" between seams, it should turn out quite nice.

It will be roughly 8% overfilled, but with 7" spacing this could be a good thing to fight dead spots.

The loft should be at least 2". (when you are hanging)

This data is based on some 3D modeling, and on some experience.
Every hammock system will work differently depending on several factors

Good luck on the project, and please share pics when you are done.