What is the differance....?

[canoe]

What is the differance in the down fill number and the oz. number. What so these mean?

[mudsocks]

This is a topic that comes up pretty frequently around these parts. This thread does a pretty good job of addressing your question.

[canoe]

Thanks Oct that reading was perfectly muddy. So is fp the ratio of down to feathers? Am I understanding that correctly? Higher the number the more down in the fil

[mudsocks]

To horribly oversimplify things the higher the FP the more efficient it is at trapping air. The higher the efficiency less down is needed. This translates to weight savings.

[JP_dog]

Higher fill power equals more puffiness with less weight.

Lower fill power means less puffiness and more weight.

Higher fill power generally means less feathers and more of that wispy miracle of creation that seemingly floats on air. The wispy bits are the down, and they don't really look that much like feathers.

Less fill power usually means more of the less efficient feathers are in there. At the very least, the down isn't as fluffy. This is a gross gross over simplification.

There is a big difference between 600 fill and 800 fill, (in my limited opinion) the 800 being more costly but more desirable. Between 800 and 900 there isn't as great a difference.

All that said, if you take a quilt, say 3" of loft, or puffed up to 3" thick, the one with 600 fill will be heavier than the 800. Again, this is a gross simplification.

Does that help?

[HomeMadeHiker]

Fp is the volume (in3) one oz will occupy. 800fp = 800 in3 per oz, 650fp = 650 in3 per oz and so on.
The fill amount (given in oz or grams) is the quantity of down inserted in to the item.
Often times with commercially available down items you'll get a down to feathers ratio. Ie 80/20 = 80% down to 20% feathers. If you see that fraction you usaully don't get a FP. This is lower quality as feathers don't insulate nor do they compress.
How's that?