I just finished up a new synthetic quilt using some 5oz/yd Apex. It is just a flat quilt, with a drawcord footbox. I used breath 1.1oz ripstop nylon as the shell and liner and got a final weight of about 19.5 oz. It is a pretty easy project, but there really isn't much info online about how to make a synthetic quilt. So I put together a guide on how I went about doing it. I'm working on a way to add a head slit without compressing the insulation and will post that once I have something that works. I hope this can help some people. It is my first time putting something like this together, so I would really appreciate any comments on how I could make it better.

http://kringlelight.wordpress.com/2011/11/15/sin50/

Chris, this is very helpful, thanks for the post. I'm going to be sewing my quilt in the next couple days, using the exact same materials as you. I'm still debating whether to use a drawstring/velcro enclosure or to just sew it up. I see the flexibility of having a blanket if I want it, but I also like the idea of it being a little bit warmer without any drafts in the footbox...

Do you find that at 51" at the top, it's sufficient to tuck under your body a little bit when you're lying down? Or are you going to use some kind of strap attachment under your body?

I like the flat design because it is meant to have a head slit so I can wear it in a similar way to a JRB Stealth. I am just working on a more efficient way of inserting that then I have in the past. I've never really had a draft problem in the footbox though. It cinches down pretty tight. And it is just a tad bit easier to do than a footbox I would guess. Here's a picture of the footbox cinched down.



As for width, the 51" in the pattern includes to 1/2" seam allowance along the sides. So what I got was a width just under 50" wide (after insulation expansion). I have about the same body shape as you, 5'10", 155lbs, and I think this is more than wide enough. I can tuck plenty of it under me. I've had quilts at 48" that still worked well for me as a side sleeper. the should region, at 50" wide, actually folds all the way around me almost.

As for straps, I didn't put anything for them this time because I purposefully made it a bit wider than in the past. But, you can add just four loops of grosgrain in as you sew the sides. Then you can just string some shockcord through them for straps. I think I mentioned adding the grosgrain in my guide.

Just ask if you have any other questions. I hope this all helped a bit.

Very nice tutorial. How much bigger do you think you'd make it for a 6'2" 200+ lb guy? I'm also curious about footbox dimensins, as I have size 15 feet. I really hate feeling constricted...

I've been going back and forth about making a karo step baffled down quilt or a synthetic one. Synthetic has a lot of advantages (cost and simplicity being two, and cost being the bigger one), only disadvantage is a bit of a weight penalty, but the weight of your quilt is still about half of what my current 30F bag weighs...

BM

Sizing shouldn't be too hard. As for length, the 74" is just about the right length of me. It came out to be just under that in reality but still works well for my 5'10" height. I would say for 6'2" that 78" or 79" should be long enough.

The width is something that a bit of experimenting would help. Size 15? Wow. Taking a guess at that will be tough, but what I would suggest is to stand on a piece of poster or cardboard and draw a circle around your feet that seems like how much space you would want for them. You can then measure this circle. The circumference of that circle is about how wide you want the quilt to be at the foot. I really wish I could give you a more exact number. From a google search your feet are probably about 2" longer than mine, so you would probably want to add somewhere like 4" as a quick guess. On the width, depending on how slim your body type is, I would suggest about the same increase in width. The 50" is VERY generous for me, even sleeping on my side, so maybe 2" or 3" only if you sleep on your back. You could once again do a measurement of your chest, but include your shoulders, to see about what you would need there as well.

The good news is, a quilt 4" wider at the foot and head and 4" longer comes out to be only 22.9 oz theoretically for fabric and insulation. It isn't the lightest option out there, but at a cost of about $80 bucks probably, it is a great cost/weight ratio.

Also planning a similar quilt. Why did you choose to sew the insulation on the outside rather than the inside?

also, i have been considering the issue of the head hole. Initially i planned on just sewing through, and maybe adding a rectangular "plug" of insulation to fill any gap. But maybe using a baffled slit (that doesn't compress the insulation around it) would be lighter? how to add this is a different question, but probably before sewing the edges of the quilt.

Adie

I'm also curious about footbox dimensions, as I have size 15 feet.

Next time you lay down, position your legs however is comfortable for you and let your feet relax and assume whatever position they want. For most people the feet will be as close (or closer) to parallel to their legs than perpendicular. So foot size is as much a factor affecting quilt length as it is affecting footbox girth.

I really hate feeling constricted.

Mock up a quilt using a flat sheet and safety pins, experiment until you find dimensions that provide enough wiggle room for your needs. Add two inches to those dimensions if you are using thinner insulation (for seam allowance and to allow for insulation bulk) ... add one more inch for every inch of loft over 1 inch

I've thought about how to add on that baffle and have one thought. I'm going to do some testing with stitch witchery and the insulation. I've used this stuff on nylon and silk, but not with Apex. So once I get some free time, maybe over Thanksgiving week, I will try it out on some scrap fabric. Hopefully, this and some hand stitching would allow me to add in the slit without compressing anything.

As for why I sewed the insulation on the outside is partly for looks and partly for long term strength. I prefer to not have structural stitches on the outside if it can be helped. It just gives the possibility for stitches to pop and start unraveling. By sewing it and then flipping it, I can easily hide all of the raw edges and these very long stitches. Plus, and I haven't tried this yet, but it seems to me that keeping a rolled hem down the entire length of the quilt could be tiresome or just hard.

Jim, thanks for the comments on testing the new sizes. I agree on the feet bit. I normally sleep on my chest, with my feet stretched all the way out, so the longer feet may mean adding 5" or 6" to the length rather than just 4" and maybe 2" in width instead of 4". Also, his idea of making a mock up is a great idea. I did that the first time I ever made a quilt like this. I just took an old sheet I had and pinned the dimensions that I was planning on.

Good clear directions.
You said it was comfortable down to around 35 degrees or so with some added clothes...not bad!
How well does it compress in your pack, or stuff sack?? cantaloupe size??
I hope when im starting mine in a few weeks here that i can PM or something to ask questions if need be...but now that ive read this...im going to place my order next week for materials!!!!

I haven't actually put it into a pack yet. I am heading out for the AT on Thursday to do a four day trip, and I will be testing it out then. I'll be sure to update with info like compression and warmth after several days of testing.

Im fairly new here, so anything we can all do to help each other along is greatly appreciated. Im thinking your quilt should compress down pretty small....at least it would be more than half the size of a marmot synthetic 30 degree sleeping bag i have...and that packs down pretty darn small....well...for a synthetic bag of course...
good luck and let us know how the trip goes!

Thanks for the very well thought out suggestions. Those are some fantastic ideas to dial in some dimensions.

What is the general consensus on, what I think is called, a differential cut? Where the fabric on the outside of the quilt is cut to bigger girth dimensions than what's on the inside, so when you pull it tight around you, you aren't compressing your insulation and losing loft...Seems like it would be pretty easy to incorporate into a synthetic quilt, little more complicated with a down quilt because of all the baffles.

Anyway- that is if it's even considered being a benefit worth all the fuss of making.

BM

Chris, You have produced one excellent set of instructions. Thanks for putting these together. I think you have struck a great balance between ease to manufacture, cost, and utliity that make this quilt a great contribution for those wanting to get started in making their own gear. Makes me want to make a synthetic quilt.

Jamie

Thanks for all the support. I'm really hoping this guide will be able to help people like a bunch of the guides that I have found on so many other things. For anyone trying the guide, please feel free to post here, on the blog or PM me in some way if you find anything wrong or maybe notice a way to make it better. I'm a big open source nerd, so the more people that help, the better.

I had a chance to try the quilt out the other night in the mid 20's. I was wearing good layers, with a cap3 and Alpine Light jacket and long pants + wind pants on my legs and midweight wool socks. I think I would have been completely comfortable at these temperatures had it not been for my dog continuing to steal the quilt from me. If I get a chance, I will try it again without her. I can say with two quart bottles in the foot to prevent freezing, the foot may have been a bit too small. I'll continue to test that and may add 2" in width to it.

I ordered my material yesterday and should be ordering the climashield by the end of the week!
Open source has become my new favorite thing! Everyone sharing tips and tricks and patterns....its a MYOG/Gearaholics nirvana!