Is the shock cord on UQs affected by extreme temperatures? Vendor opinions?

[cmc4free]

One tip if you're ever looking to buy a new underquilt - for colder weather quilts like 0° or below, order it with 1/8" shock cord for the primary suspension. Not only does that help support the quilt which is heavier because it has more fabric and more down, it's also less susceptible to loss of performance in the cold.

I have a fairly heavy -20° Loco Libre Carolina Reaper with 3 ounces overfill. Total weight is close to 40oz. Coldest I've had it is -16° and I noticed no change in the performance of the 1/8" primary shock cord. That was just a single overnight though.

[BillyBob58]

Big Duh moment - of course shock cord is affected my temperature extremes. Is anybody doubting that?

I'm betting 90% of us have never even considered it a potential problem, when depending on it to keep our UQs gap free at extreme temps- whatever the exact def of extreme temp is. Do you know exactly what temp that is? No doubt you do. And I imagine among the few who have realized it might be a problem, most of them have never considered at what temp problems might occur, if at all. But obviously you have always been aware of all of this. Though I don't recall you ever mentioning it.

I guess another "DUH moment" might be- if every one is aware that "of course shock cord is affected my temperature extremes. Is anybody doubting that?", then why are so many- in fact the vast majority- using it on their UQs to protect them from extreme temps? Perhaps you have some helpful insight about that?

[BillyBob58]

One tip if you're ever looking to buy a new underquilt - for colder weather quilts like 0° or below, order it with 1/8" shock cord for the primary suspension. Not only does that help support the quilt which is heavier because it has more fabric and more down, it's also less susceptible to loss of performance in the cold.

I have a fairly heavy -20° Loco Libre Carolina Reaper with 3 ounces overfill. Total weight is close to 40oz. Coldest I've had it is -16° and I noticed no change in the performance of the 1/8" primary shock cord. That was just a single overnight though.

Thanks, CM4, that is useful info. I don't recall Shug reporting any problems on many a minus 20 test. He even goes down to about minus 40F, but I think he has a tendency to use pods for a lot of those extreme trips in recent years. So probably not much shock cord to deal with. At least there was none with my Speer Pea Pods, his are DIY bag conversions.

[cmc4free]

I just got my -20° quilt out for another reason and seeing it now, I think the primary suspension might actually be 5/32" or 3/16" shock cord. I think the secondary is 1/8". The draft cinches at the ends look like 3/32".

This is a nearly 40oz quilt though. It is burly!

[gargoyle]

Has anyone broken their shockcord on a quilt?
I don’t recall that happening? So adjustability still remains, right?

Vendors use shockcord to fit the many, many body types of the end users.
If we were all the same size and using the same hammock (length width sag) and did not shift all night, I think you could use a static line to support the quilt. Quilts like the wookie still employ some give with the rubber strap.
Temps will effect the elasticity of anything. Roads shrink and swell, etc.
Is it enough of a % to be noticeable?
Fitment issues at 50-40* with a 20* may APPEAR good, but as temps drop and your nighttime metabolism kicks in, drafts and gaps will show themselves. So, your perception of warmth and fit will be altered.

Yes a winter UQ will be heavier. Beefier shockcord may solve it or tightening up a standard suspension may work? Shockcord is surprisingly strong and well within the capabilities to suspend weights needed for our purpose.
I replaced a majority of primary suspension with a static line on a quilt , leaving a short section of shockcord to provide some give. Adjustment can be achieved on either end ( shorten static line or SC) via an overhand knot.

I believe that the radiant/thermal energy given off the body is probably enough to keep SC in the “elastic “ zone. Possible long term exposure would make it less pliable. But in those regards it could work in our benefit. Less stretch means a more snug quilt.
Adjust as needed, in the end.

(A water soaked, now frozen, tarp shockcord shouldn’t be in this comparison)

[cmc4free]

I'm not sure it's a primary reason for the use of shock cord, but another advantage to having that elasticity is insurance against accidentally sitting in the underquilt. We want inelasticity in our hammock materials and suspension, and they're capable of supporting human weight without fail. An underquilt, though, isn't meant to be load bearing. If a person accidentally sits into the underquilt rather than the hammock (and there are numerous admissions of this happening), the elasticity of the primary suspension shock cord will allow the underquilt to stretch all the way to the ground without damage. Replace that shock cord with a rigid line, though, and something has to give... most likely the stitching or the gossamer fabric on that expensive quilt.

[gargoyle]

Can’t wait to hear of the first person who sits into their wookie!

Perhaps the rubber band will give way first?

[cmc4free]

Can’t wait to hear of the first person who sits into their wookie!

Perhaps the rubber band will give way first?

Good point, and yeah, I'm guessing that EPDM band would probably snap.