# Thread: DIY Down UQ- how wide to baffle?

1. For differential cut you use the formula:

{[((b1+b2)*H)/2]*L}\FP

• b1 = Inner Baffle spacing
• b2 = Outer Baffle spacing
• H = Baffle height
• L = Lenght of Baffle
• FP = Fill Power of Down used

Your finding the area of Trapezoid and then finding the volume of a trapezoidal solid. This will give you amount of down per each chamber.

I can tell you that I made my UQ with exactly the same measurements as the OP.

• Inner Baffle Spacing 5.5 inches
• Outer Baffle Spacing 6.25 inches
• Baffle height 2 inches
• 8 Chambers
• 1.25 ounces of 850FP down per chamber

Honestly though a little more, maybe 1.5oz per chamber, wouldn't hurt to fill it out a bit more.

2. Originally Posted by JohnSawyer
ACK!

Back to analysis paralysis!

Oh, wait.. the only thing here is you're assuming the quilt has rectangular tubes, but with the diff. cut the out fabric is more tube-like... I guess that's what the overstuff is for....

Thanks!
yeah the 20% will cover the Diff cut but i always add another oz for the diff cut but thats just me i only ever do a half inch for my diff cut never seen the need for more but some do it's all up to the maker and your needs
but no matter how you do it the end results will be the same there are a few different ways to calculate everything thats just how i was told to do it so i just stuck with it and works out every time ... but like i said the end results are the same

3. OMG...my head is going to explode!!! Really?? John, when are you coming to Ohio. Could you just help me make mine once I get the down harvested from the comforter??

4. Originally Posted by DivaB
OMG...my head is going to explode!!! Really?? John, when are you coming to Ohio. Could you just help me make mine once I get the down harvested from the comforter??
HAHAHAHA yeah i think my head did when i was trying to figure this all out 3 years ago
i lucked out i had Dutch and Stormcrow to bug for hours i learned so much from them ... if it wasn't for them i would have gone nuts LOL

5. Originally Posted by DivaB
OMG...my head is going to explode!!! Really?? John, when are you coming to Ohio. Could you just help me make mine once I get the down harvested from the comforter??
No sweat. I'll load the sewing gear in my lotus and race right over... oh... wait... I don't have one... i'll make you a deal: as soon as I win the lotto, I will come make you 3, custom uq's or have stormcrow make them for you...

Besides... you've seen my sewing (at least the early stuff) you really want ME to make you one?

John

6. Originally Posted by JohnSawyer
No sweat. I'll load the sewing gear in my lotus and race right over... oh... wait... I don't have one... i'll make you a deal: as soon as I win the lotto, I will come make you 3, custom uq's or have stormcrow make them for you...

Besides... you've seen my sewing (at least the early stuff) you really want ME to make you one?

John
I didn't think your sewing skills were bad at all!! If you win the lotto, I'll be more than happy with stormcrow's and it save you the hassle.

7. Originally Posted by G.L.P.
also LxWxH/fill power
i pretty much use 5 inch wide Chambers on every quilt but you can make them as wide as you want

say your making a UQ 56x45 and want it 3 season so use 2" baffles
rule of thumb has been 2" for 3 season and 3" for winter it's not set in stone but i found there pretty true in regards to temp ratings

so 56x45x2/800 (fill power) = 6.3oz of down needed for the said airspace
so with 20% overfill around 1.2oz so 7.5oz needed... all you need to do is add up the amount of chambers you made 5" wide at 45" would give you 9 so just divide your amount of down 7.5oz by the amount of chambers 9 ..7.5/9 = .83 or .8oz of down per chamber
this is just another way to do it ...figured i would put it out there to give you another option
Spot on!

I'm still debating on whether or not to make a video on "How to make an underquilt." But, unless the girlfriend wants one, I won't be making one anytime soon anyways because I have 4 of my own.

Fronkey

8. Originally Posted by Fronkey
Spot on!

I'm still debating on whether or not to make a video on "How to make an underquilt." But, unless the girlfriend wants one, I won't be making one anytime soon anyways because I have 4 of my own.

Fronkey
I'll buy the material and you can make mine for your video. Deal?

9. Originally Posted by Fronkey
Spot on!

I'm still debating on whether or not to make a video on "How to make an underquilt." But, unless the girlfriend wants one, I won't be making one anytime soon anyways because I have 4 of my own.

Fronkey
yeah i keep telling myself i'm going to make a video as well but i'm lazy when it comes to videos .....
i still didn't edit the one i made for the NJ hang HAHAHAH
i'll be making my new summer UQ in march half cuben half whatever i feel like using LOL... i might get some 7D for the outer shell but it's going to have 1.5 inch
baffles 5oz of down 40F quilt should be 48x40 when it's done i'm trying to get it down under 10oz ...

10. Originally Posted by Fronkey
Spot on!

I'm still debating on whether or not to make a video on "How to make an underquilt." But, unless the girlfriend wants one, I won't be making one anytime soon anyways because I have 4 of my own.

Fronkey
I'm sure some day, you will invent the Kiba'mock... pup's gonna need a quilt!

I say "Video On!"

Cheers

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