Optimize 308g. 800Fill, 20.5oz.45?F,$93 China sleeping bag to 16 oz?

[Paul French]

MISSION POSSIBLE???

<span style=”text-decoration: underline;”>Your mission, if you choose to accept it:</span>

How to make an OK sleeping bag, Amazon link below, into as warm as practical AND lower weight from 20.5 oz down to 16 oz or less?

<span style=”text-decoration: underline;”>Mission plan of attack:</span>

Collective brain dump of all feasible ideas by the amazingly large amount of experience, creativity and just plan good sense of the members here. Presented ideas may be improved upon with positive suggestions but no idea presented is a bad idea.

I spent about 8 hours yesterday reading every post on over 30 pages of MYOG that I thought might be relative to this project and most were wonderfully helpful, positive and thoroughly enjoyable.

This page is tongue in cheek since I was very surprised to see it was almost 4 AM when it occurred to me that it might be time to hit the hay. Talk about a book that you cannot put down!

   Mission begins on next post.

Link to the details of the Mission subject:

https://www.amazon.com/gp/product/B01LZKAC25/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

 

[Paul French]

Here are some of my thoughts.

I have probably spent over 100 nights in a hammock with a variety of top quilts with a large insulated Klymit Static V pad under me and I somehow always manage to end up with a leg sticking out several times each night and wake up cold. While my preference is a sleeping bag please don’t feel limited by that when you present you ideas.

I have slept in the bag the last week and it feels similar to an Army patrol bag, 40 to 45 F.

In addition to the specs in the thread title, the subject bag :

does not have a hood,

does have a bungee cord neck closure but no draft collar,

is approx. 78″ tall and when zipped is 27″ wide at the top and 22″ wide at the foot,

has 14 full bag length baffles (“tubes”) that are 4.5″ wide at the head and 3″ wide at the foot,

the down tubes are sewn clear through top and bottom fabric( I probably will just wrap an Army Wobbie over everything, Suggestions?),

the tubes near the foot are packed pretty solid while at the head of the bag are maybe 70=90% full, and

the zipper is full bottom and one side but there is no zipper draft tube,

I am a great fan of Big Agnes bags ( I have at least 5 of their down bags, I am NOT a fan of Big Agnes inflatable pads).

 

My current thinking, subject to what you folks suggest, is

to remove some lower tubes and reconfigure the bag like a Big Agnes but to fit a Klymit 72″x 23″x 2.5″ pad (70 year old body),

since I am a side sleeper, it will be tricky to leave sufficient girth for my knees that will be pointing side ways and still keep the foot and chest girth appropriately and not overly sized.(suggestions?)

I would like the foot box area to be narrower than the 23″ pad width but need suggestion on that also

I will cut the bag length down(measuring and testing four times before I cut once) to where my neck is plus sufficient length stretching room,(I am 70″tall and the bag is 78″ long so I can easily take 10″ off of the bag length AND weight and still have ample length for the neck closure and stretching room.

make an ample down neck collar using material and down from removed bottom tubes and re-positioning the existing collar bungee,

remove the bottom and the first 10 or so inches of the zipper and

then decide if using the down removed from the bottom can do any good by overfilling the remaining tubes.

I an too old to have brain storms so that represents the extent of my “brain drizzle”.

 

Thanks very much for taking the time to read this. I hope you have time to share your ideas to help me accomplish this mission.

Paul

aka almost 50 years ago “SSG Hawk”

[David Thomas]

My first thought is that you can’t cut it down that much (10″) and still have it drape over your shoulders and allow for the foot box room around your feet – otherwise, the foot box will be compressed by your feet and lose much of insulate value.

Maybe fold the 10″ of the top of the bag over and tape it in place, sleep in it, and decide for yourself before you start cutting.  I’ve found I want a sleeping bag to be significantly longer than I am, unless in some SUL set-up in which I only want to cover my lower body and am relying on a puffy, gloves, hat, etc, for my upper body.

[Paul French]

 

Thanks for your response David.

I get your point that the gathering of the material close to my neck will consume length. Thanks to you I now see that I made what must be a common error with many posts talking about their first attempt producing a short bag.  Nice save there, David.

I climbed into the bag as is and you are absolutely correct. At most, only 2 inches could be cut off. Of course my shoulders are 6+ inches from my neck. There will be no shortening of the length.

Do you have any thoughts on changing the girth to appropriate dimensions for the foot box versus my knees turned side ways versus my chest with folded arms?

Thanks,

[Paul French]

Surprising update.

First of all the puny little zipper works just fine.

In preparation for turning this China (pre-tariff) $93 supposedly 800 fill down bag into a Big Agnes knock-off to ride over a MASSDROP 60″ x 20″ insulated Klymit, I removed much of the down from one of the tubes that will be replaced by the Klymit.

The down was stunning, Not a feather to be found and beautiful 3/4″ to 1/4″ single fluffs floating around the room since I forgot to turn off the AC. I’m very impressed.  I am going to order sonmme 800 FP from KYLE just to compare.

So far
<h1 id=”title” class=”a-size-large a-spacing-none”><span id=”productTitle” class=”a-size-large”>AEGISMAX Outdoor Ultra Light Goose Down Compactable Sleeping Bag, 78 x 31 – Inch is better than I expected. </span></h1>

[Paul French]

Update:

I cut down a USGI closed foam pad to 20″ and have been binder clipping the bag to the cut down pad with different girths and a cobbled up closed foot box,and have slept in it and tweaked the various girth dimensions and foot box sizes.  I settled on a 60″ girth to comfortably allow room to wear a puffy parka etc.

This girth allowed me to empty a second full length down tube, leaving 12 filled tubes remaining.  Not a feather in the total 44 grams of down removed. Each tube’s down clocked in at 22 grams validating, so far, manufacturer’s claim of 308 g. fill.  When I received this bag, the foot area was tightly packed with down which I attributed to the manufacturing process. Since using the bag for 10-20 nights and some heavy duty shaking, I think there is room for more fill since portions of some of the tubes do not fill out. 44 spare grams of down divided by 12 remaining filled tubes = 3.6 add’l grams of down per remaining filled tube, 3.6/22 = 16% increased fill or 44/10 tubes=4.4 g/22 g = 20% increase or 44/8=5.5 g/22= 25% increase. I plan to try adding 3.6 g to one tube and see how well it fills the tube.

A couple modifications I plan to make and would very much appreciate any suggestions or war stories if you know of a better approach:

In one of the Forums I read about making a sleeve around the foot box where you can slip your sit pad into. I plan to do that and improve the cheap envelope/zipper style sleeping bag bottom by adding a circle bottom probably out of 2 layers of 3.6 oz/yd APEX @ .9 inch thickness each and a provision to be able to slip in a different piece of slip pad over that circle while I am sewing.

I think who ever thought about that putting your closed cell sit pad over 12-18″ bottom was a genius. As long as I water proof the circle and also a few inches up the bag/quilt when (not if) my feet touch not only the inner net but also the inside of my single layer tents hopefully no or much less soak thru.

As this bag has no baffles and is sewn thru, to minimize the cold spots, I bought a 30″ x 60″ piece of 40 gram 3M Thinsulate (about $10+frt). I have some lite weight, appropriate type material to cover the Thinsulate sewn (or probably Velcro or bungee corded) around the edges of the top of the bag/quilt. I estimate this will add 5-6 oz in weigh, and maybe more if I cover the Thinsulate on both sides which makes sense for the 2 or 3 oz it might add. I may or may not Nikwax the top of this top blanket. I probably will add a collar to both the head and foot end of the top blanket similar to a hammock under quilt since it would be easy to do as I go rather than having a do-over.

This Thinsulate exercise might just be putting lipstick on a pig but it will be an interesting experiment, as is the entire project.

BTW: Member Ken M. told me where to get 40 gram 3M Thinsulate (about $10 + shipping for 36″ x 60″). Thanks Ken!

Regards

Paul

[Paul French]

Update
I installed a shade tree pad/quilt retention system using 1/8th” bungee cord and tighten the quit to the point that I can toss and turn (flip flopping side sleeper) and still have room for a puffy of Temp. go North. I gave it a test sleep last night and all was well even though  I was sleeping on my 22 or 23″KLYMIT PAD where this frankenquilt is planned for the Mass Drop 20″wide klymit pad.

I already have emptied the down out of two of the original full length 14 down tubs. Each down tube has proven to include 22 grams of pretty nice down. Last night I proved that I can empty the down out of two more down tubes and still leave a good pad to quilt seal. (4x22g)/(10x22g) means that I can over-stuff the remaining tubes each by 40% with the down that I removed from the sleeping on/crushing bottom down tubes.( if my math is not correct, I have already purchased 20 oz of  750 down.) This cheap china “envelope” sleeping bag has 14 sewn through 4″ WIDE down tubes, meaning likely cold spots at the sewn through. The tubes allow maximum loft of 1.5 to 2″ I will have 22 gram x 4=88 grams(3.1 ounces)from the bottom now empty tubes.
I am going to try seam ripping the sown through seam between 2 of the 4″ tubes wide tubes making an 8″ wide tube from my neck down to mid thigh and see how much additional down will be required to fill two 4″ tubes vs one 8 ” wide tube. I already have a mess free method  of removing the down and I think that 2″ x 8″ opening to replace the down should be fairly easy.

Some one mentioned that 8 inch wide tubes might be prone to unpleasant t down migration. If testing proves that to be the case, I think I can hot-glue some light weight baffles were the stitching originally was.
Time do some more night timr testing. ALL COMMENTS, SUGGESTION AND RELEVANT LESSONS LEARNED GRATEFULLY APPRECIATED.
Paul

[Paul French]

Surprising update

In the process of removing the down from tube 3 and 4 that I Don’t need to have underneath me, I started to seam rip the sewing between two tubes. What I found was not just a single or even a double straight top material through the bottom material stitch, Rather there is folding over of material so that there are possibly 4 layers of material on both the top and the bottom layer being sewn.  Surprising quality for a pretty cheap bag.

So far this bag has demonstrated :Very nice white down with ZERO feathers, a zipper that has not snagged once in about 25 nights of use and quality sewing.  I am liking Aegismax.
<h1 id=”title” class=”a-size-large a-spacing-none”></h1>

[Sam Farrington]

“Surprising quality for a pretty cheap bag.

With so many sewn-thru seams, you will not get much warmth for weight.

[Author]

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