Down Proof & Baffles

[nacra533]

I have yet to work with down but I plan to soon. I need some help on down proof fabrics. I have lots of DYI fabrics and netting at home.

What constitutes downproof? Is there an easy / eyeball test?
I have 1.1 DWR ripstop, and I am pretty sure it's downproof based on everyone else's UQ. So I should be good for the shells.

For the baffles on the UQ and TQ, I am considering mosquito netting. I have several different types of nettings on hand with very small holes. I don't know the names of any of them.

How can I determine if the netting is downproof? OR should I just use the ripstop for the baffles?

If I use the netting, do I want it "stretchy" or fairly firm? My thoughts are "stretchy" baffles are less likely to tear, but I don't have anything to base this on.

[Just Jeff]

Downproof usually just means it's calendared or has a weave tight enough to keep the down in. I don't think the DWR actually adds to the "downproofness" but DWR is often downproof.

If you have DWR, it's probably downproof enough for the quilts. Even quality commercial sleeping bags aren't 100% downproof...if you see a quill poking thru, just grab it from the other side and pull it back in.

I've even used untreated 1.9 oz ripstop, which isn't downproof, and I haven't had a problem with leaking down. It's the insulated hammock so not used the same way as a quilt, but it still gets stuffed/unstuffed with no problems.

No netting is really downproof, but it doesn't need to be. The baffles just keep most of the down in the right place so you won't notice it moving around and creating cold spots. You could use DWR as well, but it's not necessary. Sometimes 1.1 oz DWR is lighter than bug net, though. I wouldn't use "mosquito netting" with the bigger holes, but make sure it's some kind of noseeum with the smaller holes.

Stretchy would make it less likely to tear, but I don't know if it's necessary or not. I used stretchy netting for my baffles, though.

[Jsaults]

In the late 70s I owned a Stephenson's Warmlite sleeping bag. These were quite unique, having a built-in sleeve for a foam pad and long pre-dating the Big Agnes bags with the sme basic design.

The ripstop of my bag continually "leaked" tiny down barbules which had broken from the main quill nub. Quite obnoxious, as they got all over my wool sweaters and early Patagonia fleece! I looked like I had been tarred and feathered without the tar.

Stephenson's claimed that the fabric was actually doing it's job perfectly. They said that when a barbule broke from the nub it no longer contributed to the lofting properties of the down. Hmmmm.

Sold that bag to an unsuspecting teen.

Another argument is that when a pinfeather pokes out of the fabric you might as well pull it out, because it is just a component of the fill that had not been removed during the processing. (Highest quality down has the least pinfeathers).

Just a couple of things that make you go "Hmmmmmmmm."

Jim