Down Over Fill Percentage
Posted: 25 July 2007 10:20 PM   [ Ignore ]  
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Using the 800-Fill Power down available from thru-hiker.com; what percentage of over fill is recommended for a sleeping bag?

For example:
Suppose a baffle chamber is 50” wide, 5” long, and 3” high, giving a volume of 750 cu in.
800-Fill down should occupy 800 cu in. per ounce.
So, 0.9375 oz of down will fill the baffle chamber under ideal conditions.

However, experience and industry practice indicates that a greater quantity of down is needed.
It would seem that most commercial bags employ approx. 20% over fill, so in this example…
0.9375 * 1.20 = 1.125 oz.

Is 20% reasonable with this down?  how about 10-15% ?

Thanks!
Cheers,
Eric

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Posted: 26 July 2007 02:52 AM   [ Ignore ]   [ # 1 ]  
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This is a good question and one that doesn’t get discussed much.

You’re exactly right, though: commercial bags tend to overstuff at @ 20%. I think anything between 10 and 20% is reasonable.

AYCE

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