On Sleeping Bag Weights and Cold Ratings

Posted by: Kieran

On Sleeping Bag Weights and Cold Ratings - 06/25/09 01:32 PM

Hello Everyone - I'm new here and this is my first post. This will also be my first MYOG project. Been reading lots of good stuff and I think you may have the key to what I need to know.

So, I need a sleeping bag that is suitable for backpacking. Even if I could afford the $300 or whatever for a nice one, I'm kind of a bigger guy, meaning that climbing into a standard mummy bag leaves zero room for movement. Making my own oversized mummy bag seems to be the best option available to me.

The fabric patterns appear to be straightforward enough, but I want to make sure I make something with the proper cold rating. So I was looking at CLO ratings. Take a look at the "Yeah, but who hikes in a business suit" section of this article:

Based on the info of that article, I could purchase 6 oz Primaloft Sport ( http://thru-hiker.com/materials/insulation.php ), and would have a CLO of 4.74, giving me a cold rating of roughly 40 degrees. Also, based on them saying it's 6 oz/sq yd, am I estimating that if I needed 2 yards of the 60 inch insulation (or 3.33 sq yds) @6 oz/sq yd, the resulting bag would weigh 19.98 oz plus shell and zipper material. Am I understanding all of this correctly?

Thanks in advance for any and all helpful info!
Posted by: lori

Re: On Sleeping Bag Weights and Cold Ratings - 06/25/09 11:58 PM

welcome to the board!

A sleeping bag is an ambitious first project. The final weight of it would depend on a few things, such as shell material (momentum? ripstop?) and zipper (full length or partial? metal or plastic?).

I have no experience making a sleeping bag, but I have made backpacking quilts with climashield xp and also with a kit from Ray Jardine's website (ray way quilt with alpine upgrade) and found that I far prefer the insulation in the ray way quilt. The Climashield wasn't as compressible or lofty as the insulation in the Ray way (3D? the website doesn't say).

Based on my experience making the quilt, I would guess that you will need more material for an oversized mummy. Your estimate is about what I had for the quilt, and I am not a very large person.

Do you have a pattern for the bag? Are you going to sew through all the layers or use yarn to quilt the insulation in place?
Posted by: Kieran

Re: On Sleeping Bag Weights and Cold Ratings - 06/26/09 05:03 PM

thanks Lori! ok - so the whole quilt thing is intriguing to me. i've never used one, nor have i heard a lot about how to use one or what situations they work well in. what's the coldest situation that you've comfortably used your ray jardine quilt in? do you think you could have pushed it further (colder)? how much does it weigh? i'm a little confused on what ray jardine is selling, cause the purchase option on their site is closed till July. Do you remember how much it cost? Do they sell all the supplies? just a pattern? finished quilt? thanks again!