Originally Posted by
BillyBob58
Very interesting topic-and great for general discussion of ideas and concepts- but, OK, here comes Mr. "slow to catch on"!
Except for synthetic quilts, aren't all quilts a "loft up design"? A synthetic quilt –at least with sheets of insulation such as Climashield-has the sheet of insulation sewn to the inner/upper layer of an UQ(at least in the ones I have had like my old synthetic Yeti). Then, after that quilt is removed from it's stuff sack and hung under the hammock, the insulation will expand downwards, away from the hammock and the inner(or upper if you prefer) UQ shell, down towards the outer- and normally much looser(if a differential cut at least) outer(which is also the downward) shell. So, as far a I can tell, this type of UQ "expands down".
But I assume we are discussing down UQs, correct? Or maybe not, I guess the OP does not actually say "down". But that is certainly the type of UQ or TQ that is mainly discussed around here.
So if we are primarily discussing down UQs, it seems to me we are dealing with a "loft up" situation. When you remove your down under quilt or top quilt from it's stuff sack after the days hike, the down is maximally compressed, and when you hang it under the hammock, gravity will pull the Down towards the ground, where are it will be perhaps 1/4 in. of loft, or who knows maybe one inch, and then it will proceed to puff up. It will expand in an upwards direction 1 or more inches depending on rating. It will be" up lofting". This will be the case with either a down top quilt or under quilt. Seems to me like in all cases the down will loft upward from what ever surface it might be laying upon.
In fact I have started a couple of threads relating to this general topic over the years. Because I had a question about- when it comes to handling moisture(dampness–humidity– Fog– body vapor that condenses), and if there is actually any advantage to synthetic in such conditions( a debatable subject, though I think there is ), might it have even more advantages with an under quilt? Because unless there is plenty of over stuffing, it seems natural to me that down would loft to a lesser degree in damp conditions, and therefore might not be able to Loft up enough to make contact with the top of the baffle and the upper shell and my back. Creating a very cold gap. This would not be near as much of a potential problem with a top quilt, because even if some loft was lost, it would not cause a potential gap since the down–though maybe not as thick as it was before the dampness–would still be laying down in contact with your body, more or less. Also not much of a problem with Climashield, since even if it had lost some loft from moisture, it would not have to loft up to reach my back, since it is already sewn to the quilts inner shell which I have pulled snugly against my back with the suspension. Now it is simply trying to- with the aid of gravity- "loft down" away from my back, but still always in contact with my back.
Of course, even if that is a possibility, that is one of the things over stuffing is meant to overcome. But on the other hand, more over stuffing means more dollars and more weight and more volume. The latter two being the main reasons to use down in the first place.
So those variables are some concerns or questions I might have regarding this subject. And of course on might just been totally missing the concept, or the point, just not understanding something.
On the other hand, your idea about some form of ultralight under hammock being used to suspend the insulation is an idea that has had some pretty good support in the past. For example, I(and perhaps another half dozen or dozen folks) have successfully added various forms of insulation into what amounts to(sort of, more or less) an under hammock. I.E. The undercover of the Hennessey Hammock Super Shelter(HHSS). This form of hammock insulation in its basic form, consist of a 2 ounce space blanket, which lies on top of an open cell foam(very flexible) pad. This pad has a very wimpy suspension of its own which holds the pad up against the hammock. However, this shock cord is very thin, and there is more elastic inside of the third part, called the under cover. This under Cover also gives more support to the pad holding it up against my back(In the hammock of course) snugly without any apparent compression. This system has always been good for me somewhere in the 30s. But when I want to go lower( my lowest was toasty warm at 6F), I have just added all manner of insulation down into the undercover, down below the main pad. Most often unworn clothing. A fleece jacket combined with a down vest has been a favorite. But I have even put a synthetic sleeping bag in there(producing some serious insulation, HOT), though the weight had a tendency to pull things too far down(in that case I had to tighten the suspension up more). The elastics in this undercover are just a little too strong for down used alone, and tends to compress it, though not all the way. Still no problem for me, because there are a couple of tricks to reduce this tension to provide a space just right for down to loft right on up into contact with the occupied hammock. I normally use something synthetic which is less compressible than 850 down, and sometimes what I use is a fleece jacket which is hardly compressible at all, which also keeps the elastic from compressing my down vest too much. This has always worked like a charm for me over the last 10+ years, though admittedly it took a bit of experimenting during those first couple of years when I didn't really understand some of the concepts involved.
So your concept of "a nano noseeum hammock that is suspended below the main hammock with a gap for the underquilt" certainly has some merit. Although some- or a lot of- experimentation to work at the details and the variables will probably be required. Experiment and let us know how it works!
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