Insulated hammock / structural underquilt.

[barefoot]

I'm having an idea.

I have a few cheap hammocks. You know the ones - the generic 9-foot 3-panel nylon taffeta ones that sell for about USD10 on eBay and elsewhere. I've paid about AUD14 for these.

I actually find them quite comfortable. I tend to side-sleep in a fetal position and I'm only 5'10", so I'm not really coveting the 11-footers that seem most favoured here.

I got one with an integrated bug net (for all of AUD18), but I don't like it much. Tends to hang bug net on my face. I think I prefer a separate bug net if I need one.

I'm still working on my under-insulation. I have a cheap 3-seasons OneTigris UQ. When I tested it in the yard the other night when it got down to about 5dgC (about 40F), it was marginal (in t-shirt, light pants and bare feet in my TQ). Completely unsurprising, that's exactly what it says on the pack. I shoved a windscreen reflector in between my hammock and UQ at 3am and slept comfortably until dawn. It will work okay on its own when the weather improves.

But it would be nice to have something else that gives me a few more degrees of comfort.

One idea I've been toying with, and reading up on, is to insulate one of my cheap hammocks. Rather than add fabric+insulation+fabric (aka a traditional UQ), and develop a suspension strategy to keep it in the correct place... why not just add insulation+fabric to the hammock fabric I already have, and sew it in place?

Then the idea occurred to me - I already have a perfectly shaped outer shell... a second cheap hammock! Two of my $10 hammocks, one sagging lower than the other, with a layer of insulation lofting between them. In essence it would be an underquilt that's strong enough to sleep in directly without slinging a separate hammock inside!

Would be hard to get a hammock-length of fabric for AUD14. I just bought a bunch of the only ripstop nylon my local fabric shop stocks, on special at A$6.50/m. Probably the same stuff you guys get at Walmart for US$2/yard. Yay for the "Australia tax" again. Anyway, that's about $20 for 9' of pretty basic cloth. Or $14 if it's a 9' hammock.

I was thinking synthetic insulation batting, because it's easy... no need for baffling... but then I scored a down queen-size bed quilt in a thrift shop for AUD8. It's rubbish quality down (even says it's about 20% "small feathers"), but probably warmer per compressed size than any synthetic I'd be able to get my hands on. Very low risk for experimenting. And if it leaks down... no big loss.

Using down, I'll need some baffles to keep it all in place. I was going to head back up to the fabric shop and get some kind of curtain mesh.... then I had the thought... why not chop up my integrated bug net hammock that I don't like? I can use the hammock for the outer layer and the net for baffle material.

I reckon I'll do longitudinal baffles. Maybe "baffle" the edges with ripstop (downproof-ish), so the hammocks will essentially be spaced a constant distance apart. I'll cut the ends off the outer layer hammock because I don't need to insulate the whole gathered length, just the bits I'll be laying on. I'll go full width, so I'm not locked in to laying only on one diagonal.

So there's my plan. Sew some bugnet baffles between two hammocks and stuff it with reclaimed duck from a thrift store quilt.

Anyone done something similar? Tips and hints? Things to look out for?

I'll post results here, successful or otherwise

[sidneyhornblower]

Insulated hammocks are definitely a thing. See the Bonefire website: http://www.bonefiregear.com/
See also the Sheltowee website: https://shellhammocks.com/

Also check out the Hang Your Own Hang podcast, episode #31 for a talk with the owners of Bonefire and Sheltowee hammock brands.

[alphabennett]

I think it could be a great idea. My concern would come from putting a lot of holes in the hammock body from sewing baffles and weakening it, but I could certainly be wrong. Sounds like you have some good materials on hand for testing!

[Otter1]

Several iterations of this exist here on the forum. Both down & sythetic.

theclark5 did quite a few great versions:

https://www.hammockforums.net/forum/...ulated-Hammock

I prefer to have mine separate, but the idea is way cool.

[leightfoot]

Barefoot, I really like your idea! I would not baffle the immediate/top hammock for the pre-stated reason of weakening the integrity of the 'lay-strength', but permanently sewing along the longitude edges (sides) and rig the ends or tack stategically to the gathered ends would maintain the warpp strength of the fabric weave (end to end). To baffle, some fabric stores sell 'pre-baffled parka matterial; all you need do is stuff the baffles (a 'patience-challenging' chore). Your idea inspires me! :-)

[barefoot]

Good thoughts about stitching compromising the top hammock fabric.
I think I have some margin on strength (they sell these things as "double" despite being only 9' by 60", with a weight limit of 200kg iirc; I'm 75kg). But baffle stitching could mess up the stretch and gather properties of cloth.
To overcome this, I think I'll use coarse zigzag stitch to attach my baffles, to allow some distortion. The baffles themselves don't need to be downproof, they're just limiting down migration, so they don't have to be sewn super tight in position.
Previous designs seem very focused on not having any stitching in the lay area. I don't think I can avoid that with my baffle concept. See how it goes.

[Hobopelican]

Is there an issue about how much insulation to use? I tend to have didferent UQ for different temp ranges...or did I read this to quickly?

[BananaHammock]

Is there an issue about how much insulation to use? I tend to have didferent UQ for different temp ranges...or did I read this to quickly?

For this setup, you make your hammock rated to 40-50 F and then add quilts for colder temps. It’s like stacking.

[MiteyF]

I did what was essentially an UQ sewn to my Dutch, works wonderfully. Once I get the shape/size nailed down on my newest DIY bridge, it will be getting the same treatment. Granted, this setup is not as "sophisticated" as you're planning.

[barefoot]

Is there an issue about how much insulation to use? I tend to have didferent UQ for different temp ranges...or did I read this to quickly?

There could be an issue I guess.

I'm new to all this, and I've only slept a couple of nights in my hammocks so far, all in temperatures ranging from -1dgC up to about 10dgC (~30 to 50 dgF). So far I've been borderline "warm enough". Haven't come close to "too warm" yet.

Anyway, if this idea works, I guess there's nothing stopping me from having a different UQ for each different temp range... just that my "UQ"s are structural, as in, they are actual hammocks and don't require a separate hammock suspended inside.

It wouldn't take any more effort or expense than making a graduated set of non-structural UQs. I'd still be up for $28 worth of fabric for each (just that mine would come in the form of two pre-made eBay hammocks rather than cut cloth from RSBTR or wherever), plus baffle material and thread, and as much fill as I need for each - whether I continue reclaiming thrift store down or step up to premium quality 900+ FP down.

Or I could add layers as BananaHammock suggests.

It's all dependent on how well this works.

I think I'll get a start on it this afternoon when the family are out. I've already cut/picked the bug net off my integrated net hammock (unpicked the zipper... now I have a 9' double zipper in case I ever need one )