Has anybody ever made/used a Reverse Double Layer hammock, thinner layer as outer layer

[hutzelbein]

There is one main reason why I never followed this approach: even with a standard double layer, blankets or anything soft and flexible will move towards the lowest point. A blanket simply bunches up under the butt and leaves the other body parts uninsulated. It's possible to prevent that by adding a suspension on the four corners - but that adds its own set of problems. About the only insulation that might work well enough would be a soft foam / open cell pad. But unless you make a pocket for it, it will move at least as much as a pad in a standard double layer hammock.

It's actually pretty easy to put your theory to the test without sewing a double layer hammock. Simply get a couple of yards of the fabric you had in mind for the outer layer, whip it, and hang it under your hammock with large diameter shock cords. Then add any insulation you like and see how well it works.

[SupraLance]

The point though is to eliminate any complexity (visual and otherwise) of shockcord etc. But I do think it could be tested by whipping together a 2 layer hammock with the outer layer either very stretchy or a ever-so-slightly larger piece of fabric. I think a same size but very elastic and not-so-slippery outer layer (since it doesn't need to hold human weight) would hold a blanket in place better than a standard DL where the weight of the person and slipperiness of the fabric contribute to the bunching, but it's just theory at this point.

But what I'm really leaning toward with this thought is a slightly larger as well as stretchier outer layer to allow a perhaps 1/2" gap before it begins to compress the insulation against the weight-bearing inner layer, which will hopefully allow for synthetic insulation like climashield to work in place of a pad, since it tends to stay together in shape but does not work compressed like a pad will. If anybody more familiar with making their own hammocks than I am wants to whip something together and test it, please report results back in this thread.

[hutzelbein]

Yes, I completely understand what the point is In my experience it won't work, though, because even in a normal double layer hammock, blankets tend to bunch up. It's already difficult to get them positioned correctly and keeping them that way until you get in. If you manage that, you can't move a lot because the blanket will move as well as soon as it's not pinned anymore.

I tried your approach by hanging a second hammock with a shock cord suspension under my primary hammock and tried putting different insulations in there (a synthetic duvet, down blanket sleeping bags, a sheepskin rug, a piece of open cell foam) - it was difficult to keep the insulation in place. I ended up adding shock cords to the four corners of the insulation to keep it stretched out.

The only way how this will work without shock cord or another method of clipping it in, is if you can find a way of stiffening the insulation so that it won't bunch up. Or find insulation that is fairly rigid. I got my best result with a piece of open cell foam (the stuff that is used for sofas or some mattresses). But in order to be sufficiently warm and cover all important areas, it has to be quite large. It might be a good solution for home use, but I wouldn't want to pack and carry it. And since I got a Wooki I have never been tempted to experiment further. I can't see it working better.

[hutzelbein]

I forgot: in my 90° hammock (a double layer that is built almost exactly like you propose with a larger second layer, only not stretchy) I tried putting in a closed rectangular sleeping bag with a self-inflating Therm-a-Rest pad zipped into the bag. That actually worked quite well, but in the 90° hammock it can't move sideways since the "bed area" is well defined. If you would do something similar with a gathered end, you would need to find a way of keeping it in the right place.

[BillyBob58]

I forgot: in my 90° hammock (a double layer that is built almost exactly like you propose with a larger second layer, only not stretchy) I tried putting in a closed rectangular sleeping bag with a self-inflating Therm-a-Rest pad zipped into the bag. That actually worked quite well, but in the 90° hammock it can't move sideways since the "bed area" is well defined. If you would do something similar with a gathered end, you would need to find a way of keeping it in the right place.

I was just about to post the same thing. My Hammocktent 90* has a loose pad pocket that is roughly 3" deep or at least meant to accommodate a 3" thick pad. When I put a quilt in there by itself( no pad) it seems to stay put except for some reason under my feet. Other than right under my feet, it seems to stay in place once I get in the hammock. But it can be a hassle, when not also using a pad, getting the quilt correctly positioned in the pocket. Some combo of pad and puffy insulation seems to be the beat way to go, or just with a thick pad. If I ever decide to use the quilts more often, I will rig up some Velcro or Grip Clips or something to make positioning the inner quilt easier. Which will also help me keep it in place, even under my feet.

[SupraLance]

Yeah, I think key to this whole idea will be to completely fill the space provided. 3" is a lot of thickness. I struggle with the the thought of how thick would be best, with the idea being that you would use different materials for different temperatures and nothing at all between the layers when it's hot. It would be great if there was a combination of insulation efficient enough to achieve 20degrees at say only 1" thick, and then a different combination of insulation that achieves 40degrees at the same thickness that could be switched in when needed, so the pocket is always either completely empty or completely full. Anywhere in between is not going to to be satisfactory.