Want to make an Underquilt

I just made a full length syn quilt out of argon and two layers of 3 oz primaloft gold Primaloft has a higher Clo .92 than climasheild .82 so it is higher warmth to weight ratio and found primaloft to be very compressible and relatively easy to work with ( I did no special quilting). Got to test it out in the sierras on a three day trip saw low 40's and was very warm with just a baselayer, and the foot box open. I am a young man with a fast metabolism and was well feed, IE a warm sleeper but I think it would have no problem taking it down to the mod 20s if I had too. I got the primaloft from Rockywoods. I am actually considering converting it to an underquilt so I would love to see the finshed project when your done. I would give you the weight but my scale is hiding at the moment.
-Matt
http://www.rockywoods.com/Fabrics-Kits/Insulation-Fabrics/PrimaLoft-Gold-Insulation-Fabric-100-gsm

Go their for insulrex insulation and underquilt directions. I made one and turned out great. $50 for materials.

Is Insultex insulation any good? How much would I need for an Underquilt to be warm at 30degrees? How heavy is it? This is my first sewing project and I wanted to do it on the cheap. Insultex is about1/3 the price of Climashield.

Insultex is a thin fabric that traps warm air between layers of it. It only really works for underquilts because the layers hang loose, trapping the air. The guide at diy gearsupply tells you how much to buy for 35 degree quilt (3 layers differentially cut). I spent $100 on enough material for two underquilts. They work down 35 and can be pushed further depending on your system. Pros- cheap, light, compact, durable. Cons- only really good for underquilts because it must hang to insulate well. There are plenty of you tube videos about these DIY synthetic UQ. Took my wife and I 15 hours to make two I think and it was our first DIY project. She is great at sewing. Good luck.

What size under quilts did you make and what was the final weight? What is the compressed size?

Insultex is basically a super thin layer of CCF foam between two layers of scrim sewn in a cross pattern. I built an insultex UQ and it was okay. 2 layer with Apex baffles on the ends and I would guess maybe 50dF or so. Also had a third layer I could add in which should add another 5dF just guessing.

Its not particularly inexpensive by the time you buy 3-4-5 layers and not that light either but its easy to work with.

If I made another IX UQ I would just have an outer M50 shell and skip the inner shell.

Also you cant just stack 3 layers. You need to differential cut and sew.

It does not really breath except for the sewing punctures where the scrim is sewn on which is basically nil.

It is easy to work with.

I also build a top quilt liner out of IX. Intended to go inside of my modular quilt. I added breathable panels of halved 2.5 Apex and silk, but by the time I actually had it breathable enough, about 1/3 of it was silk and Apex.

In the end for the UQ I decided I would have been better off to have used Climashield and ended up selling the IX UQ. Also it does not really compress as much as roll up.

Due to compressibility and me headed towards smaller packs I decided to stop screwing around and bought a hammock gear 20dF 3/4 UQ that weighs 16 oz which is a very nice piece of gear.

If you really want a solid 30dF UQ I would guess 6oz Apex but you need end baffles to seal it. 5 oz might do if you are a warm sleeper.