Today or tomorrow I'm going to order the thru-hiker quilt kit + the extra 3oz of insulation and make myself a 20 degree winter quilt + balaclava.

I've read/skimmed and bookmarked quite of few of the MYOG quilt threads, but I have a question I haven't seen answer yet; I want to make my quilt Arc shaped. I have a Nunatak Specialist to use as a model,and a girlfriend who can help me approximate the pattern and teach me how to sew.(or does a pattern exist out there already?)

How, though, do I determine how much down to put in each baffle, as they'll be different lengths?

I'm shooting for 12oz or so of fill in the quilt with 2-3 in the balaclava, depending on how much I lose stuffing the quilt.

No worries. Simple volume. Desired finished height of stuffed baffles X baffle spacing X length of each baffle. For example, I like a denser fill, so I use a slightly shorter baffle height than finished height... if I want 2 inches of loft, I'll probably use a 1.5 inch baffle. With that example, then, 2 (height) x 5 (width) x __ (length). Your top baffle might be 56 inches, your lower ones might be 38 inches. Just plug the number in for each baffle. Divide that number by the fill power.

So 2 x 5 x 58= 580 c.i./ 800c.i. fill = 0.725oz for "top" baffle. Note, however, that I get a better end result by using a lower fill power for my calculations... so although it's ~800FP down, I generally run my calcs using 700FP. In that case, 580c.i./700c.i. = 0.829 oz.

See, this is why I always had problems with math. I read the thru-hiker article on making the quilt, and how to calculate fill power for the whole quilt, and it never occured to me that I could use the same formula for each individual baffle.

so although it's ~800FP down, I generally run my calcs using 700FP

That's kind of why I'm ordering 3oz extra down. I'd rather have my quilt an 1 or so heavier and have it be an honest 20 degree (or lower)quilt.

Are you using Momentum or 1.1 ripstop? I'm convinced that 1.1 ripstop isn't worth having.

The thru-hiker kit comes with .9oz Momentum. I have a JRB quilt using 1.1 ripstop, and a Nunatak using 1.0 Quantum, and I definitely prefer the Quantum.

the arc shape is a french curve (well 2 that oppose each other i think.)You can get almost the same thing by using a straight taper and rounding the top edge, i never do this but to each their own.

I use excel to plug my lenghtxwidthxloft into and have a formula to spit out the oz per baffle then i have it convert that to grams and round up to the next gram. I then take the remaining grams of down and add them to the lower baffles. Having it right in front of me allows me to change the amount of down used per baffle and still track my overall usage. Adding extra to the foot/legs is nice as most people carry warm tops but don't always have as much warm stuff for the lower half. A gram of down is a lot surprisingly.

-Tim

Tim, thanks for your input. As someone who actually has a financial interest in selling people quilts, it's great that you're so quick to help other people make their own.

Adding extra to the foot/legs is nice as most people carry warm tops but don't always have as much warm stuff for the lower half.

I was thinking along these same lines. With a 20 degree quilt, I'm going to be carrying my MB Down Inner Parka at the very least.

the arc shape is a french curve (well 2 that oppose each other i think.)You can get almost the same thing by using a straight taper and rounding the top edge, i never do this but to each their own.


Besides my shoulders, I'm a pretty narrow guy, so at the very least I'll taper it, as why have that extra fabric and down where I don't need it.

I can just fit under my 48" wide rectangular JRB Shenandoah, but I'd be better off with about 4" more.

I'm probably going to make the quilt to the dimensions of the Nunatak Expedition, (58"shoulder,52"hip45"foot)which is another reason I'll need that extra 3oz of down. I want to be able to use it as an overquilt for my Specialist (55"shoulder45"hip38"foot") to get me down to around Zero degrees before adding insulated clothes. It'll also be nice to have that extra width to be doubly sure against drafts when using it alone in cold weather.

Edited by jrmacd on 12/01/2009 16:09:06 MST.

I don't make down/m90 quilts (i guess i do if someone orders a custom one, but i don't have a down/m90 product) so i have nothing to gain by keeping my secrets. I am quick to help because i love making gear, and i love helping others develop that same sense of independence that i love.

I only make gear for money now because it allows me to make gear almost every day. Even making new stuff for every trip doesn't allow me to make gear that often. I just love making gear, especially making something lighter than other options and built just for me(or my customers).

-Tim

P.s.
The easiest way to calc the amount of down needed is to just do the biggest tube, add 10% and use that number for every tube. That way as the quilt narrows it gets warmer and you do less math.

Edited by MarshLaw303 on 12/01/2009 16:24:06 MST.

Also realize that your quilt will shrink a bit once you stuff it. Well, I guess you're using the kit, though, and I'd imagine it compensates for that. Counting on fabric at 60 inches, getting it at 58.5, then losing ~0.5 inch per side automatically got me to ~57.5 inches just in fabric, then lose a bit of girth with the loft (Guessing I lost ~1.5" of girth with ~2" of loft?). You should be fine with the quilt, Thru-hiker offers great products, lots of people have made the quilt, just saying in case someone else wants to make one without a pattern...

Tim-If my budget was twice what it is, I'd almost certainly be ordering a 2.5" loft Epiphany, but as it is, I'm fortunate enough to cohabitate with someone who studied textile construction in college and understands things like 'french curve' and 'differential cut.'

Brad-I had considered losing some of the width for the seams, but hadn't though about what I'd lose in loft. Hmmm. . . well, I have to make experiment with measurements, but I could probably make due with 52" shoulder width and use it as an under(rather than over)quilt with my 55"shoulder Arc Specialist. I fit okay under a 48" wide rectangular JRB quilt as a stomach/side sleeper, but some gaps do open up when I roll over. I think 4" of extra width(plus using the understraps, which I never do as its a 40 degree quilt and drafts aren't a big deal at those temps for me)would still be okay.

But assuming thru-hiker sells me genuinely 60" wide fabric, if I lose 1" for seams + 1.5-2" for 2.5" of loft, I should be okay at 57-58" of width. I'm probably going to go for your denser fill, as I believe Richard Nisley showed that there can be some benefit from that. The Nunatak Arc Alpinist has 11 oz of fill for 2.5" of loft, and so I figure 2.5 inches of loft with maybe 14 oz of fill will get me to 15-20 degrees.

Jim, Here is my experience...maybe it will help. I recently finished a thru-hiker quilt kit (momentum 90). Thanks to many folks here for your help.

My quilt is a half taper with draw cords at both ends. The top width is 52" to half way down. Then it straight tapers to 40". To make this hapen I added an inch to all sides for seams so I cut 54" top and 42" at the bottom. The quilt is 78" long. I added 1.5" for draw cord seams so I cut the quilt 81" long. The baffles were cut to 2" tall and spaced at 6". I used 11.5 oz of down in the quilt saving .5 oz for a hole plug for the footbox. The finished quilt weighed alittle over 20 oz and lofted 2.5"+.

I am 5" 10" tall and weigh about 165 lbs. I have a JRB quilt and the few extra inches helped out. I just got back from an overnight trip day before yesterday. The night time temp dropped to 15 degrees. I slept okay but was a bit cold. I dont think this was because of the quilt, it was from the sleeping pad. I was using a scant 42" long 3/8" GG thinlight pad...the cold came up from below.

I do think that my quilt could handle 3 extra oz of down to really overstuff it. But I don't really need it for warmth so I'm good with the lighter quilt.

The other thing I noticed was that the footbox was roomier than I would have thought. Almost too roomy. Next time I will do a 38" footbox.

Jamie

Jamie, that helps a lot. I found out today that I'll have to put off the quilt making until January, as relatives are visiting town next weekend, and I know I need to block off a full day to spend working with the down. Then it's Christmas shopping and holiday travel=no time.

I'm definitely sewing my footbox as this will be a cold weather quilt, but it will be a short footbox(feet only)so in non-freezing weather, I can get my feet out to vent, as I get hot feet. I also be adding understraps a la the Nunatak Arc concept.

I'll also go for the roomier footbox as I get restless feet.

I got back and forth about the extra 3oz of down. I think I'll end up ordering it as a $25 insurance policy in case there's a down disaster while trying to stuff the quilt. At worst, I'll have an ounce or two left over to make a balaclava.

Jim, It sounds like your quilt will be similar to mine. I'd say if you are going for colder weather then by all means order to extra 3 oz of down...that's what I would do. And yes to sewing the footbox for a colder quilt.

You are right on target as to allowing a day for the down. I think I spent a solid 4 hours transferring the down then several hours more sewing it shut and adding the extras (straps, etc). If you check out my thread where I asked for help you will find a way to transfer down without loosing any. I'd say I moved 99.9% of the down flawlessly. It is a slow process but using a shop vac works like a charm.

Good luck,

Jamie