Sewn Through and Baffle

[PoppaZ]

Whats the difference in sleeping bags/quilts that are sewn through and those that have baffles?

[kncats]

On any down filled sleeping bad, quilt or garment you need to have some way of keeping the down in place or it's all going to fall to the low points and you end up with nothing but the inner liner and outer shell for insulation in spots. The way this is done is by making "compartments". The two basic ways of doing this are by either sewing right through the inner liner and outer shell or by using baffles. The sew through method is quick, light and easy. However, where the line of stitching is you have no insulation, just two layers of fabric. This is fine when you're talking about a bag or garment with a fairly high temperature rating. When you need to ensure a layer of insulation througout you have to use baffles. Think about the center piece of an "I" beam. It allows the down, or other insulation, to maintain its loft and keeps the two layers of fabric from touching each other. Baffle material is usually something very light such as bug-netting. All it needs to do is keep the down in place, it doesn't provide much in the way of structural integrity. This also means that it can be damaged by rough handling of the bag or quilt.

[Roland]

Nice explanation, kncats.

[weary]

On any down filled sleeping bad, quilt or garment you need to have some way of keeping the down in place or it's all going to fall to the low points and you end up with nothing but the inner liner and outer shell for insulation in spots. The way this is done is by making "compartments". The two basic ways of doing this are by either sewing right through the inner liner and outer shell or by using baffles. The sew through method is quick, light and easy. However, where the line of stitching is you have no insulation, just two layers of fabric. This is fine when you're talking about a bag or garment with a fairly high temperature rating. When you need to ensure a layer of insulation througout you have to use baffles. Think about the center piece of an "I" beam. It allows the down, or other insulation, to maintain its loft and keeps the two layers of fabric from touching each other. Baffle material is usually something very light such as bug-netting. All it needs to do is keep the down in place, it doesn't provide much in the way of structural integrity. This also means that it can be damaged by rough handling of the bag or quilt.
The baffle is why you should not wash a good bag in an ordinary washing machine. The constant agitation damages the baffle. I've found the type of washer makes less difference with a sewn through bag.

Baffles make construction more difficult and thus more costly. Sewn through is okay for a light summer bag. But not for a low temperature bag.

Weary

[hammock engineer]

Good explanation.

Baffles also would allow for more loft thoughout the quilt. I think a constaint 2" would be hard to get otherwise.

[Toolshed]

excellent explanation - Especially the I-beam analogy. I think of baffles as little compartments all with walls ceilings and floors - Like a big square piece of baclava Everything junction has a corner and all surfaces are flat, whereas sewn through, has no walls. The ceilings and floors bend together more like a stuffed pita bread.

For a cold weather bag, I think your find cheaper manufacturers getting around the whole baffle bit by sewing through, but using less down and creating a secondary inner bag (bag within a bag construction) where all the seams are offset, so, ostensibly, you should have the benefit of consistent thickness throughout the bag. The inner bag also has to be made a bit smaller (I think it is still called "differential cut") than the outer, so you don't "press through" the insulation by pushing the inner bag against the outer bag compressing the down and and creating cold spots.

[Tinker]

The type of washing machind does make a huge difference in washing any delicate article, especially down bags and clothing, since the down gains so much weight when thoroughly wet and puts a strain on the baffles. A front loading washing machine, as big as you can get (forget about cost) is the way to go. Gentle cycle, cool wash and rinse.

The baffle explanation is very good, by the way.

[peter_pan]

Maytag's Neptune front loader works great....Super, super spin cycle gets virtually all the water ( and also weight) out... have washed my personal quilts 3-4 times in the last couple years... all good as new, fluffy too.

FWIW, I think a lot of damage is done when the inexperienced person tries hand washing, as most water remains and the heavy wet bag is often lifted without supporting it from the bottom...Squeeze excess water out...never, never wring a wet bag/quilt out... this gets exaccerbated when the over soaked, not spun, bag is put in a large tumbling dryer... tennis shoes etc when added too early in the drying potentially do more damage...If using a commercial dryer check it every 10-15 minutes as the temperature regulators are often bad or at least inacurate on these

BTW, I find a JRB quilt after washing in the referenced Maytag on gentle setting dries in about three 40 minute Maytag cycles on the next to lowest cycle, maybe 4 cycles for the thicker winter model .. without any tennis shoes, balls etc.

Hope this helps.

Pan

Pan