Determining Fill power...first underquilt, need help

**lpranal** · 10-10-2013, 11:41

Ok, so I got all the materials together and followed (or should I say had a friend follow!) the instructions for the red river gorge underquilt. I have the shell and am just getting ready to fill it. My source is a down sleeping bag I found at the thrift store (for $6

). The bag is fairly heavy (over 3 lbs) and only measures approx 72" x 60" square. I'm trying to figure out if this is a good source for the down, or if I should buy "fresher" / higher FP down from one of the usual DIY suspects.

The bag doesn't have much info on it other than "manufactured exclusively for spiegel" (the parent company of eddie bauer). It doesn't seem very old, but the material is really heavy duty ripstop nylon and there's a huge beefy zipper on 3 sides of the square. It seems these things are contributing the most to the heavy weight of this thing. My question is, is there an easy way to tell what the fill power of this down is? I have a scale that measures in grams, so I could probably go that route, but it seems there'd be lots of room for error. I don't want to waste my shiny, new (very well made!) shell on some bogus down!

**Boston** · 10-10-2013, 12:13

Typically a bag like that will be 550 or 600 FP.

You could try to measure the FP. Fill a known volume with fully lofted down, and measure the weight in oz.

FP = in^3 / 1 oz

**gmcttr** · 10-10-2013, 12:16

Originally Posted by lpranal

...My question is, is there an easy way to tell what the fill power of this down is? ...

I'm going with No.

Down fill power is derived by placing an ounce of down in a cylinder of a given size, fluffed in a particular manner and a flat plate weight (yep...of a given weight) is place on top of it, etc. to arrive at a fill power rating.

**Vincethebutcher** · 10-10-2013, 12:19

I just made mine and was kinda in the same boat. See if you can find the bag online somewhere, it will tell you if you can find it. Or find a bag that is similar. I would guess though if the bag is that heavy for that size your probably looking at no more than 650fp. Or you could at least use that for a safe guess.

Maybe try washing it and weighing it again though. It may be full of dirt or something. In which case it may be better.

I was told mine was close to 750-800 FP but I used 700 ad my unit of measure just to be safe.

Good luck, let's us know what you find.

**lpranal** · 10-10-2013, 14:43

Originally Posted by Vincethebutcher

I just made mine and was kinda in the same boat. See if you can find the bag online somewhere, it will tell you if you can find it. Or find a bag that is similar. I would guess though if the bag is that heavy for that size your probably looking at no more than 650fp. Or you could at least use that for a safe guess.

Maybe try washing it and weighing it again though. It may be full of dirt or something. In which case it may be better.

I was told mine was close to 750-800 FP but I used 700 ad my unit of measure just to be safe.

Good luck, let's us know what you find.

Excellent point about washing it, I should probably do that anyway as if it was washed, it was probably done with regular laundry soap and that's definitely not helping the loft-ability of the down!
Last time I worked with down I did the dry method (read: grabbed handfuls of the stuff in my shower, stuffed them in the baffles). And it wasn't too bad. The feathers mostly stayed confined to my tiny bathroom. Thinking about giving the wet method a go since I'm gonna be washing it anyways... can anyone give some input that's tried both?

**Hamish** · 10-10-2013, 15:48

Find a box or some sort of square container (makes it easier) that is at least 1000 cubic inches. That is only a 10 inch square box. Weight out exactly 1 oz of down, compress it briefly, and then let it sit for 24 hours. Then measure how many inches of material you have. For example, if you have a box that is 6 inches long, 8 inches wide, and 14 inches tall and 1 ounce only fills 9 inches. Then it's 6 x 8 x 9 = 432. Since it was exactly 1 ounce of down, you know for sure that the fill power is 432. Hope this helps and good luck with the quilt. I too am working in a similar project using salvaged down of unknown fill power.

**lpranal** · 10-10-2013, 15:51

Originally Posted by Hamish

Find a box or some sort of square container (makes it easier) that is at least 1000 cubic inches. That is only a 10 inch square box. Weight out exactly 1 oz of down, compress it briefly, and then let it sit for 24 hours. Then measure how many inches of material you have. For example, if you have a box that is 6 inches long, 8 inches wide, and 14 inches tall and 1 ounce only fills 9 inches. Then it's 6 x 8 x 9 = 432. Since it was exactly 1 ounce of down, you know for sure that the fill power is 432. Hope this helps and good luck with the quilt. I too am working in a similar project using salvaged down of unknown fill power.

Appreciate the methodology. I will give it a shot!

**lpranal** · 10-10-2013, 19:09

Should also mention there is a LOT of down in this little bag. unzipped as a single layer it's about 4" of loft, and it's 9" tall when it's all zipped up (closer to 10" in the middle). So hopefully after a good washing and re-fluffing this stuff will prove worthy.