UQ Baffle direction

[Roadrunnr72]

I was reading the the sticky "Red River" to DIY UQ. Does it make a difference on which way the baffles run? The sticky makes them "around" the UQ, and some others make them length wise. Is there an advantage doing it 1 way over the other?

[Trooper]

I'm assuming longitudinal, or from head-to-toe, would keep the majority of down in place. The other direction would allow the down to gather directly below you, which may also be beneficial.

Perhaps some short baffles across your body in the center, and then longitudinal baffles on the sides would be best. Or just make boxes.

[MAD777]

I think longitudinal is best. There is only a slight amount of curvature in that direction compared to the curve across your body. So, the down would be more prone to migrate with transverse (across your body) baffles.

[koaloha05]

I've used the JRBs and WB Yeti. JRB run across, Yeti lengthwise. Maybe the length of the baffles relative to the length of the uq factors in. Both designs work very well in these cases.

[Knotty]

My thinking is the shorter a baffled section the more likely the down will stay put.

But I doubt it really matters.

[TiredFeet]

TeeDee went through this when he designed and made our down under quilts.

We saw several photos of various under quilts. For some reason all of the under quilts made up to that time used side to side baffles - no longitudinal baffles anywhere in any photos. In some of the photos if "appeared" as if the down was tending to sink toward the bottom of the channel and was slightly compressed. I say "appeared" since we were not able to examine any of the setups in person.

TeeDee finally decided on longitudinal baffles for 2 reasons:

1. gravity compression towards bottom - again we couldn't swear that it was happening, but with longitudinal baffles the whole issue was avoided.
2. no differential cuts needed - if using side to side baffles for an under quilt the question of differential cutting of the baffle to avoid down compression raises it's ugly head. Many people had been developing complicated computations and methods for cutting and sewing the baffles with a curve to conform to the bottom of the hammock so that the 2 shell fabrics weren't pulled closer together by the baffles and compressing the down. With longitudinal baffles the whole issue of cutting the baffles in curves is simply avoided and a non-issue. You still have to make the outer shell fabric wider than the inner shell fabric, but that is trivially accomplished

[Youngblood]

I was reading the the sticky "Red River" to DIY UQ. Does it make a difference on which way the baffles run? The sticky makes them "around" the UQ, and some others make them length wise. Is there an advantage doing it 1 way over the other?

The basic trade-off is sewing shorter baffles versus stuffing fewer baffled chambers.

The physics of horizontal versus vertical baffles make it a wash unless there are some particular issues involved-- like differential shaping in one direction only, shifting down in an under filled baffled chamber, variable thickness in areas, etc.

[Roadrunnr72]

Thanks to all. Will have to think about which way when I get around to making one. Hopefully I will get started after the holidays.