SPANDEX: The Perfect Fit for Underquilts

[leiavoia]

It saddens me that in 2018 i'm still seeing people regularly post about poorly fitting underquilts, cold spots, and "dialing it in" (Examples: 1,2,3,4,5,6,7,8,9). This should not be happening. Having been a victim of these issues myself, i'm on a mission to make this kind of nonsense go away forever. We're going to fix this. Here. Now. And we're going to do it with...

SPANDEX!

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Over the last several months, i've been doing a lot of research and prototyping of underquilts using stretch fabrics. I put together the results and wrote a big article for you. It details how to choose fabrics, how to build an underquilt with stretch fabrics, and the benefits of doing so. It contains example directions on how to make a DIY Costco down throw spandex quilt. I also present a number of theoretical avenues for further research and tinkering.

Read the exhaustive how-to article at:
http://leiavoia.net/spandex


Let's quickly outline the key points:

• Adding stretch fabric to the ends of a quilt body makes it hug the hammock.
• Total elimination of cold spots.
• Eliminates the need for a draft collar, "triangle thingies", secondary suspensions, cinch cords, and other crutches.
• Basic Wooki-style gathered-end design is easy to build, but more advanced designs available, depending on your needs.
• "Stretch Mesh" fabric is $6-12 per yard. (You only need one yard.)
• Tons of fabric options, colors, prints, and yes... CAMO!
• No advanced sewing skills required.
• Quilt hangs up with a drawstring through the gathered end using a simple slipknot.
• You can also hang it with a shoelace-style tie (as pictured). This completely seals it and reduces a quilt's tendency to rotate.
• Biggest downside is a weight penalty of ~2oz over a conventional side-channel shockcord suspension. This can be reduced or eliminated with advanced designs, but will never compete with the clew suspension for overall weight.
• Works with both long and short quilts.
• Works with Wooki-style biased lay designs.
• You can retrofit existing quilts with spandex. (Consider this if you have a badly behaved quilt and want to ramp it up to it's full potential).
• You can convert costco blankets, snugpak blankets, comforters, and sleeping bags with spandex using the same technique.

Of course, this is not a new idea. The old Speer SnugFit used stretch fabrics years ago. But for reasons that are beyond me, neither the commercial market nor hammock hobbyists have continued with this concept. I'm guessing this is because of either cost or lack of knowledge. But i have good news: stretch fabrics are cheap and easy to sew! I don't know why more people are not already doing this.

Last year, i posted an article on how to make a clew suspension for underquilts. I still recommend that suspension type for backpackers. However, i believe its fiddly nature and bizarre looks have put off a lot of people from even trying it. Hopefully spandex underquilts will be more approachable for DIY folks. And maybe, dare i say, commercial vendors? That would be nice.

I hope folks benefit from this info. If anyone would like to share their own personal results with spandex underquilts, i would very much like to see what you come up with. If this thread produces any additional innovations, i will update the original article. (I cannot update this post in the future). I'm not going to post the entire article's content here, but i leave you with this delightfully annoying teaser-trailer instead.

Happy hammocking!



Pictures of my first prototype Costco quilt:
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[HandyRandy]

This looks like an epic post! Too late for me to check it out now, but I wanna throw in one question before I head out. How does this accomplish venting if the temps go up? I have wondered this about the Wooki and similar quilts before too.

[leiavoia]

How does this accomplish venting if the temps go up? I have wondered this about the Wooki and similar quilts before too.

Just loosen the attachment cord.

That said, i have never in my life needed to vent an underquilt. That includes taking my 20* quilt out in the Summer.

[HandyRandy]

Just loosen the attachment cord.

That said, i have never in my life needed to vent an underquilt. That includes taking my 20* quilt out in the Summer.

I haven’t had a chance to use an UQ in the summer yet. I have seen people post about venting, so I had to ask. But if that’s true, then this idea makes a lot of sense. It sounds like the sewn closed footbox equivalent of UQ’s in a way.

[heyduff]

This looks like an epic post! Too late for me to check it out now, but I wanna throw in one question before I head out. How does this accomplish venting if the temps go up? I have wondered this about the Wooki and similar quilts before too.

For venting? I thought of that...if the fabric is stretchy, it could be push to one side or or the other out is the way and brought back when wanted while still in the hammock. That was my thought...


Sent from my iPhone using Tapatalk

[hutzelbein]

I don't want to be a party pooper, but similar to the clew suspension this approach will only work really well if the underquilt is either wide enough (I'd say 57" at least, but 60" is better), or if the spandex is attached so that the underquilt / insulated part ends up suspended diagonally over the needed width. Also, you don't need the carrier fabric to be elastic. The Wooki has shown that it is completely sufficient to have only a short elastic element - in this case a short rubber band on the foot end. This saves quite a bit of weight.

Just for the record, I have experimented with the clew suspension, but I could never get it to work half as well as the Wooki-design. If I would build an underquilt from scratch, I would definitely copy the Wooki.

[Otter1]

I don't want to be a party pooper, but similar to the clew suspension this approach will only work really well if the underquilt is either wide enough (I'd say 57" at least, but 60" is better), or if the spandex is attached so that the underquilt / insulated part ends up suspended diagonally over the needed width.

Just for the record, I have experimented with the clew suspension, but I could never get it to work half as well as the Wooki-design.

Questions:

1) Why is diagonal required?

2) Why is the width so critical?

4) What went wrong in your experiments?

Thank you

[hutzelbein]

Questions:

1) Why is diagonal required?

The diagonal is only required if the quilt is narrower than the area you're occupying when you lie in the hammock. With a "normal" underquilt, the quilt has to follow your lay direction. This is possible, because most underquilts are suspended by a shock cord that only goes around the long edges. When you lie in the hammock, you have to push the quilt into a diagonal direction. This has two drawbacks: it puts pressure on your body (mostly head and feet) and the seal is not as good as it could / should be. With my standard underquilts I always had problems using them below ~60°F (the lower, the more problems) because I started feeling even small gaps. So I tightened the suspension, to get a better seal. This in turn put more pressure on me, because naturally, the underquilt had to be pushed harder into a diagonal lay.

Only when I got the Wooki I really noticed how much more inline my lay was due to the underquilt. I have been able to lie more diagonal (without any pressure) since then.

2) Why is the width so critical?

4) What went wrong in your experiments?

I'll answer these together because it's the same problem. It already takes some force to push the underquilt diagonal when it's suspended by one shock cord. With the clew it became even more difficult to push the underquilt into the desired position. And the better I needed the seal to be, the tighter the suspension had to be and the more difficult it became to bend it. The only quilt I was able to get the clew to work with was a 60" wide monster underquilt, because this was wide enough so that it didn't need to turn diagonally. With the narrower underquilts, my head and feet would simply slip beyond the underquilt and the underquilt would snap back inline.

I hope I explained this understandably.

[BillyBob58]

The diagonal is only required if the quilt is narrower than the area you're occupying when you lie in the hammock. With a "normal" underquilt, the quilt has to follow your lay direction. This is possible, because most underquilts are suspended by a shock cord that only goes around the long edges. When you lie in the hammock, you have to push the quilt into a diagonal direction. This has two drawbacks: it puts pressure on your body (mostly head and feet) and the seal is not as good as it could / should be. With my standard underquilts I always had problems using them below ~60°F (the lower, the more problems) because I started feeling even small gaps. So I tightened the suspension, to get a better seal. This in turn put more pressure on me, because naturally, the underquilt had to be pushed harder into a diagonal lay.

Only when I got the Wooki I really noticed how much more inline my lay was due to the underquilt. I have been able to lie more diagonal (without any pressure) since then.



I'll answer these together because it's the same problem. It already takes some force to push the underquilt diagonal when it's suspended by one shock cord. With the clew it became even more difficult to push the underquilt into the desired position. And the better I needed the seal to be, the tighter the suspension had to be and the more difficult it became to bend it. The only quilt I was able to get the clew to work with was a 60" wide monster underquilt, because this was wide enough so that it didn't need to turn diagonally. With the narrower underquilts, my head and feet would simply slip beyond the underquilt and the underquilt would snap back inline.

I hope I explained this understandably.

I also was not getting why you felt the width was so important. But that seems a very logical explanation. In the quilt I asked you about, a ~ 45" wide(and tapered) Sierra Madre Research, which has a single elastic strap on the end of a fabric triangle each end(in addition to some side elastics of some type), I have noticed a tendency for exactly what you describe. Although, it is still new to me and I am still experimenting with how to use it, so that might be a factor. In fact, based on what has worked with previous UQs, I may have had t too tight per the manufacturers directions. This quilt has toggles meant to fit D rings on the hammock of the same brand, so this would be a non-issue when used together. In my case, when using with my HH's side tie outs, which are an approximate fit, it stays nicely in place. With my narrow Claytor and wide Wilderness Logics, there are no tie outs on the hammocks, but by attaching a single piece of thin elastic cord from a loop near the right foot of the quilt to the hammock suspension, that seems to have done the trick easily enough. I may add some toggles or tie outs to these hammocks to use with this quilt.

But I do see this tendency related to width. I think it has been an issue with other quilts, but I can see it may indeed be potentially more of a problem than it is with the more traditional suspension.

[BillyBob58]

I don't want to be a party pooper, but similar to the clew suspension this approach will only work really well if the underquilt is either wide enough (I'd say 57" at least, but 60" is better), or if the spandex is attached so that the underquilt / insulated part ends up suspended diagonally over the needed width. Also, you don't need the carrier fabric to be elastic. The Wooki has shown that it is completely sufficient to have only a short elastic element - in this case a short rubber band on the foot end. This saves quite a bit of weight.

Just for the record, I have experimented with the clew suspension, but I could never get it to work half as well as the Wooki-design. If I would build an underquilt from scratch, I would definitely copy the Wooki.

Well, yet another fascinating and promising concept- spandex- before I have even had time to try my first CLEW!

Re: your comment above about no need for an elastic fabric carrier: I wonder if any of this relates at all to an UQ I have recently been trying out, and one that seems to be working quite well- and after the very 1st attachment and without tensioning enough to raise the unoccupied hammock? It does have a triangle, but not spandex(too bad). They describe it as "the unique stretch tech pattern contours perfectly to your back". There is an elastic strap attached to the tip of the fabric triangle(which I think actually has a small amount of down in it), plus elastics in each side which seems to snug the sides up nicely and keep the quilts long edges straight, and actually cause it too hug the occupant(hugs are nice! ) but I don't know what all is involved with that side part.

I'm wondering if that triangle and single elastic strap is using any of the principles described here? Or not really?