It's similar to the pain felt when our fellow forum members see us wordier fellas postOriginally Posted by BillyBob58
It is hard to believe. And now I realize the pain associated with losing a long held and unquestioned championship!
It's similar to the pain felt when our fellow forum members see us wordier fellas postIt is hard to believe. And now I realize the pain associated with losing a long held and unquestioned championship!
Last edited by Just Bill; 03-19-2018 at 16:14.
Maybe slim, lol.
I guess my only question would be... how is VBL use relevant to your original questions?
On paper... A VBL layer has nearly zero value in a CLO system or as insulation. It's primary function is to preserve the insulation by preventing body vapor accumulation in prolonged periods of low temps.
In real life...
Some folks report some real world value from using them to bump things a bit... 5* or so roughly. In this case, usually when worn directly over a baselayer.
I'd concur with that and have tried my WPB shells for this, though I haven't personally tried a full waterproof suit such as a sil-nylon or similar shirt and pant combo. Though many of us employ the bread bag liner for footwear that is often as much to prevent melting snow from reaching our socks as it is to serve as a VBL.
I did mention using a Bivy sack as a means of supplementing a system in warmer weather. Maybe a 10* pick me up when pushing things.
Overall though... the conversation began with you specifically asking about pushing sleep systems beyond the rating and wandered from there. (and yes this guy is responsible for much of the wandering, lol)
But to circle back...
I think we all agree that there is some value in using some clothing, with some caveats we all seem to agree on. (over compression, damp clothing, improper stacking, etc).
Presumably... if pushing things we are looking to do more with less and save weight. I have come to believe that this logic has a practical limit. Filling in 10-15* maybe.
But it costs you less in terms of piece count, weight, and pack volume to simply bring the appropriate main insulation piece to start with.
The other potential problem...
Is personal acclimation.
We also don't all live in Minnesota or sleep outside full time.
18 months ago I moved and lost the ability to sleep outside nearly full time... that 'skill' and lack of practice is evident when I sleep out now. My body simply isn't as adapted and simply put; I got soft.
I'm colder more easily simply because I got used to sleeping indoors in a controlled climate.
Even when I was sleeping outside 6 days a week minimum... it still isn't the same as being on a long distance hike for a few months. Again... I got soft.
As fer the Minnesota comment... we all know the difference between 40* in the fall (brrr, time for the wool sweater) and 40* in the spring (whoohoo break out the shorts).
It's not hard to find myself thinking that my 30* set isn't quite cutting it during that 40* fall, or that I might be able to push my 50* set with a jacket come spring time.
So when you start talking temps of zero or lower... my question is always; Coming from what?
If the two of us drive to the frozen butt hang to meet Shug and the gang...
You come from average lows of 30ish in MS.
I come from average lows of 20ish from Chicago.
Shug's been goofing in the back yard facing zero and below for months.
Regardless of sleep system you and I will struggle simply by dint of hitting 'unnaturally low' temps for our bodies.
By the end of a long weekend we will probably adapt, but those first 48-72 hours are going to be a shock to the system.
If the three of us head to hangcon in Florida... even if a goofy sub freezing night happens it would be no big deal and our 35* set would probably be fine, while the locals would be freezing to death in 20* quilts.
Our bodies are amazingly adaptable machines but they only can adapt to the conditions we give them.
I think we all cause ourselves quite a bit of grief when we try to force something to happen without considering how far we are pushing from our current position.
It's unrealistic to think you can jump into a minimalist sleep system 'off the couch' so to speak. If we haven't been out and using that system we simply get out of shape to use it.
If it's not relevant to you... then dismiss the notion.
But as a person who doesn't get out as much as I used to; it's a simple fact I have to deal with when choosing my gear these days.
It's also something I had to deal with when I was selling sleeping gear in order to better meet the needs of those who bought it.
What a long distance hiker, or even a full time tradesman working outside all day can get away with is different from a weekender coming from an office job.
Took me a few times around that circle in my own life to come to that realization. It's critical as it may be the single biggest impact on my ability to 'push'.
Go away for a day or 2, and man! I have now read my brains out, or maybe my eyes, or both, and am caught up. Thanks every one for opining. And there are some widely varying opinions, as expected!
I am going to say something that may seem almost blasphemous, or at lest stupid, but her I go again:
I don't feel any need to warm up my quilt with my body heat after I get in it. In fact, if I warm it up too much I might consider it a bit of a failure.
My goal is to retain body heat ideally in my core or at least very close to my skin,as close as possible. Any body heat I use to warm up my cold quilt or pod or bag, which will then at some varying rate escape my quilt into the cold atmosphere and drift far away and have to be replaced by yet more of my body heat, that is some heat that my body no longer has and is a negative. It might feel good as it reflects some of that heat my body has lost back to my skin, but it is still heat that has left my core to warm up a cold quilt. Too much of that sort of thing and I will find myself shivering. As I have found myself doing about twice over the last 35 years of back packing periodically a few time each year.
Now don't get me wrong! Very obviously when we get under a quilt, unless we are simply not radiating much heat, we are going to warm up either that TQ to some degree X, or we are going to warm up whatever layers we are wearing and therefore probably warm up that TQ a bit less, like maybe 2/3 or 1/2X. I'm just saying it is not my goal to warm it up, and if the layers I am wearing are preventing my body heat from warming that quilt up, that might actually be a good thing. Exactly as if I I was sleeping almost naked under a 20F TQ at minus 10F and I am cold despite just eating a hot, fatty meal and despite not having hiked much today, but fortunately I have a spare 20F TQ which I drape over my first TQ. Experience shows me that I might well soon be toasty, assuming I am not already debilitated and low on fuel(food).
May I ask all of the folks here who stack quilts when they are sleeping significantly outside the range of their primary quilt(or sometimes even when just CLOSE to the 1st quilts rating!):what is your expected result when you double up on quilts, assuming no drafts and no excessive compression of the 1st quilt by the 2nd? Don't you expect to be a whole lot warmer? What kind of results do you get? I'm betting you are much warmer.
Some of you have a big, roomy bag or quilt that is not warm enough, and you add some sort of smaller liner bag inside it hoping to be warmer. Are you warmer? I'm betting almost always, you are at least warmer, if not warm enough.
Really, assuming all the things we know to avoid are avoided in all cases(too tight, compression, damp) how is any of the above any different than wearing a down or synthetic puffy parka under a roomy quilt? Or placing the same down inside a pod between the hammock and the loosely hung pod? I'm sorry, but for the life of me I can see no significant difference.
A 5 oz/sq/yd(oe osy) Climashield TQ has 1.2" of loft, and at .82 clo per oz(about the same as 600FP down but weight of baffles must be dded) has a total clo of 4.1(.82X5=4.1), which some rate at 20F. (since I have been plenty warm in the high 40s with a 2.5 osy with clo of 2.05, and no other layers, this rating may indeed be in the ball park). Or, call it roughly 12F per clo, if every thing is perfect(dry, no drafts, good fit, etc) So 2.5 osy or 2.05 CLO X12f = 24.6F of protection. 75F-24.6= 50.4F rating. Again, I have been fine a bit below 50, so it is at least a ballpark rating. And of course, people vary, but it is ball park for my almost 70 year old self( a few years younger when I did that test, maybe early 60s).
If you stack 2 of those quilts, or build one quilt with two of those 5 osy CS layers inside the shell, for a total of 10 osy and clo total of 8.2, the rating will now be 8 CLO X 12F=96F worth of protection. If 75F is comfy with nothing minus the 96 of protection= minus 21F rating. Maybe you need something as an UQ in a hammock below 80F, if so make the rating only minus 16F, call it minus 15F. Now, before you say that is ridiculous, recall that Cannibal took the original Yeti UQ(which I also have) which was CS before it was down, and had a max of 10 osy ( 4 layers X 2.5 oz per layer) and a CLO of 8.2 to well below zero and was warm. He was a very warm sleeper, and I don't recall how far below zero he took that UQ, but it was well below. So double the CLO, double the warmth, more or less. He(and I) take layers in and out of that UQ. I bet that when we add layers, those outer layers do not warm up near as well as those layers closer to my skin.
Or, if my TQ is 5 osy CS for a total clo of 4.1 and a 20F rating(if no leaks or draft), and I either wear a Nunatak Skaha CS Apex Parka with optional 5 osy CS, (or layer the Parka over me or under my hammock in a similar rated pod), the total CLO will now be 8.2, just as though I had added either another TQ draped on top or a liner quilt under the TQ. Now, if it is 20F outside, I'm probably going to roast and sweat if I wear that parka. But if it is closer to zero I am probably going to be fine with my 20F TQ. But if it is closer to zero or below, there is no way on earth I am going to be fine if I take that 5 osy parka off and just use my 20F TQ. Not in my experience at least.
But here's the thing: Whether it is 20F or 0F outside, that 4.1 CLO parka most likely will decrease the amount that my TQ warms up. Or at least greatly slow the rate at which it warms up. But I am not taking it off if it is much below 20F, and probably not if I am cold at some temp even above 20. That is just how things have worked for me over the years, YMMV, and probably will.
http://www.adventurepoet.com/adventu...ngs-explained/
You are right: it really has no relevance to my original question, which is mainly about the pros and cons of adding or removing layers of insulation. It is only slightly related to this topic as it is one of the layers that some of us add- other than layers of insulation- under quilts or on top of UQs or in HH upper Shelters or inside pods or boots or even under jackets, etc., in order to try to increase the warmth of whatever system we might be using.
I have also experimented using them hiking or working outside when it is cold. But talk about needing minimal- or zero- layers other than the VB! That is tricky, but has been interesting. But certainly never cold! I have reported an apparent bump of 15-20F while sleeping, though I can not precisely measure it- too many variables.
I relate this mainly to cutting the continuous evaporative cooling that takes place all night long as our skin pumps out vapor to keep our skin moist. My most common use has been with a space blanket/VB under my hammock inside the the HHSS. The difference is always immediately apparent, seems like 10-20F. But maybe at least some of that is the radiant barrier of the space blanket? I don't know.
My best experiment with VB clothing was also inside an HHSS, with VB clothing at skin level, and for top insultion: a very thin poly shirt, a thicker fleece jacket, and a TQ that only weighs 20 oz for the long wide version, so not all that thick or warm. Maybe a 25 to 30F TQ? Some have called it a 40F TQ. Plus, final layer, a thin piece of nylon: the HHSS top cover over the ridge line, with about a 6" diameter vent hole near my face(but no tarp). Dry and TOASTY warm all night at 6F, most def could have gone lower, maybe below zero at least. My feet- a problem area for some folks- were over heating and sweating all night- VB socks/1 layer loose wool socks/synthetic booties. But of course, the sweat(at 6F!) stayed inside my VB socks and out of my insulation.
So, for me, I think they add a good bit of warmth by way of cutting evaporative cooling to about zero. But their best known benefit is keeping both body vapor and/or sweat out of all of the insulation except for whatever thin next to skin layer is sacrificed. For me that i the Fuzzystuff liner of the Warmlight VB clothing, which even with that liner only weighs about the same as one of my thin LJ shirts. That is their main benefit, particularly on the longer trips. But they add a lot of warmth, seems to me.
Last edited by BillyBob58; 03-20-2018 at 10:38.
Personally, it is very relevant to me. I just can't handle the cold like I could in my 20s, as you were talking about earlier. When I came off of my 30 day NOLS course (in my 30s) where I got a 24F and over a foot of blowing snow ( ON JUNE 27 no less! 9 to 11k sleeping in WY, did not have gear all that warm), I seemed almost immune to both the cold and sleeping on the ground. I notice these days I seem a lot more sensitive to the cold. Although, that was only 4 years ago when I set my personal best of 6F in a hammock. Still, I handled the cold better 30 years ago!
Really simple answer- around 20* and as you approach zero- all bets are off.
Simple answer-
70*F- the second quilt's rating= how much warmth you will add.
So if you have a 20*, and add a 50*- you get a zero. (70-50= 20) (20-20)= 0
That original chart is Enlightened Equipment's. Though it works well enough to around zero. It works better when the inner shell is down.
I have further said- add 10* (or subtract depending on how you want to word it) when you hit zero, and another 10 below zero.
So if you put your 50* on your 20* that is zero, but in real life figure 10*
If you were stacking a 30* on a 20*... that works out to -20 but I would figure between zero and -10 until you tested it.
As stated upthread someplace... the CLO formula breaks down around zero. Around there it is no longer a simple linear relationship... really around 20* it falls apart a bit.
Complex answer- I disagree with your math.
You and I (and the forum at large) have had this Apex talk before...
My position is the same. I think anything beyond 5.0 Apex is useless and you should bring down.
I rated and tested my Primaloft gold stuff at:
45*= 3oz=2.76 CLO
25*= 6 oz=5.52 CLO
When stacked together roughly 10*F. That was with a base layer, appropriate hats, and on the ground on a proper pad(not in a hammock).
Even then... those ratings were for a fit hiker and easily 5* off for someone like myself (approaching 40, not as active). So I always told people to figure 5* more for weekend trips.
In reality then, that is 9oz of PLG or 8.28 CLO. 10 OZ of APEX is 8.2 CLO.
So at best... I would entertain using 10oz of Apex to 10*. And stop there, really 15* is probably more accurate.
Keep in mind... using one or two 'hero stories' about one person (typically very experienced and hardy) to determine ratings is a bad move.
We all know a super hero or a recall a great trip we once had back in the day.
I've used 2.5 ounce Apex into the mid 30's while soaking wet. I didn't die... but that doesn't make it a valid rating. I was also in peak shape on an FKT trip and intentionally pushed way out of bounds.
It makes a good story but not a good choice nor a useful data point in insulation math.
Further application of Synthetic beyond 8 CLO likely has a half value at best or more accurately you need to fall back on the mind of Ray Jardine: he was the first I am aware of who came up with the insight that while CLO is useful, at some point you must flip back to LOFT. I tend to think around 20* is when that switch starts to apply.
Depending on who's chart you like:
3" of down equals zero F. (in a top quilt).
At 1.2" per 5 oz batt, that's 2.5 bats of 5.0 Apex to get to zero or 12.5 oz= 10.25 CLO.
That does align with an optimistic CLO system at zero.
Myself and a few others use roughly 1.64 CLO per 10* after 60*. So I find some fault with your math to be blunt, though I acknowledge that where to 'start' has always been hard and I think what misleads folks.
Roughly... 70* baseline, drop to 60* with baselayer and even the shell material... and count from there. It matches quite a few synthetic systems if you look hard enough including enlightened equipment.
So again back to 70* start... 60* for baselayer and shell... then count ounces per sqyd.
2,4,6,8 system is 50*/40*/30*/20*
You'll note I don't include 10oz or zero degrees. I don't agree with it, and I'm not alone. Enlightened discontinued the zero degree synthetics a few years back.
From there you could figure 5* per 2 ounce added if you insist.
Layering an APEX parka is even sketchier math IMO.
Besides the fact you have worn it all day, it is APEX. My obvious bias aside there is a reason that clothing is made from short staple fills like Primaloft and not out of Apex.
I wear and layer Patagonia Primaloft products as clothing fairly successfully.
I have worn Patagonia clothing, including vest and jackets of roughly 60 or 100 GSM thickness under 20* top quilts to around zero.
I have layered my 45* summer synthetic over the 20* down to get below zero.
But I never wear more than a single piece.
Here's a real world from the Windy City Winter hang-
It's deep cold and we are on a group hang... I have on a vest and jacket while hanging around camp. Roughly mid twenties during the day and expected low of 5* or so.
By the numbers... At best I'm wearing a 55* synthetic 'bag' over my baselayer in the form of my clothing.
OR adding roughly 15* to my sleep system.
I have removed my shell pants, heavy gloves and shoes. I will slip the vest off and put it around my feet.
But left on my long johns, baselayer and other garments.
I took off my WPB shell and hung it on the RL to block any breeze- I had no tarp or sock.
So my 20* down top quilt + 15* of clothes is about 5*. (allowing some losses and not counting my 5* baselayer)
Layering my 45* summer quilt over the top of that mess adds 25 * (70-45= 25*) and now I'm roughly at -20.
But as mentioned... I back at least 10* off that.
And another 10* off for drinking a few beers/whiskeys, standing around at a group hang, and generally not being in great shape.... And I was pretty good at 1*, which is where it ended up...
The smarter move was probably to bring a zero degree top quilt, but I don't have one. Tough titties... I don't need one often.
I had a hot drink, slipped my shoes off and directly warmed my feet and socks by the fire before heading to bed.
I did wake up at some point around 4 or so, had a smoke and tossed a log or two on the fire.
I also 'went to ground' but I had a bridge along with air pads... which in the air crap out around 20* and bridges can be dumb in deep winter... but no biggie. On the ground zero is easy enough and that took 5 minutes to swap... it was kind of expected so I had my 'midnight sit' when awakened by the chill.
The next night was closer to 10*... I set up a gathered end and slumbered all the way through for the 6 hours or so I wasn't talking somebodies ear off, lol.
I had a zero UQ and the same setup on top as the previous night.
So yes...
Stacking quilts works (if your math is right).
Wearing clothing works (if you don't push it too far and run the math like it's insulation)
Clothing, while moving, is not equal to clothing while sleeping.
Keep in mind...
pushing a 50* bag to 30* with clothes and tricks is a plausible option for some.
I can put the math together to mainly work with picking up 25-30* in fair weather with the right system.
I've also run the math that shows that system was a bit flawed and I should have just carried a 40* top quilt.
Doing the same as you approach or go beyond zero... doesn't work.
As many here agree... you can get away with lots of stuff when it is 40* and up... including a sloppy UQ fit.
But someplace around 20*... it doesn't matter how small your 'leak' is... it's a huge problem and will prevent sleep.
By the same token lots of experience when the temps are above 30*... doesn't apply as accurately when below 30*.
So summer success does not always equate to winter warmth when looking at sleep systems.
And if I didn't make it clear enough....
I'm not talking about taking gear from summer to shoulder. That's a broader and easier topic with options.
I'm talking pushing shoulder gear to deep winter. Going much more than 15* beyond your primary piece is not that effective.
Though I do believe that well stacked quilts can be your 'primary piece' even though they are two things combined into one... that doesn't seem to be what people want to hear.
They want to keep stacking clothing to the sky... In that case... why are you not ask the Jacks for a sniveler. Instead of killing yourself to make your clothing into a quilt. Just make your quilt into a jacket.
Works much better.
Last edited by Just Bill; 03-19-2018 at 18:48.
This?
To access it, position your cursor where you'd like to insert the degree symbol and then go to Edit > Special Characters (or Edit > Emoji & Symbols) in the Menu Bar. Alternatively, you can use the keyboard shortcut Control-Command-Space.Mar 18, 2015
How to Insert a Degree Symbol in Mac OS X - TekRevue
https://www.tekrevue.com/tip/degree-symbol-mac-os-x/
I know that you guys know ... so I get this in my head.It's similar to the pain felt when our fellow forum members see us wordier fellas post
"I must read".
I collect vintage camp stoves.
I roast coffee at home.
I feel your pain!It's similar to the pain felt when our fellow forum members see us wordier fellas post
20°
Place cursor, click edit(or control-command-space), search for "degree", click "degree", worked! Now, maybe I can remember that!
20˚ ( option-K also works!)
This has been a fascinating science lesson, and great reading. But, bottom line for me is when I am cold, I add something in the hammock and I am warmer. I sleep cold as a dead body and am always in a quilt set rated 10-20 degrees lower than I expect the temps to be. I do this to keep from having to add layers as I sleep better with less on. But, if I feel cold I find adding a mid layer or fleece liner makes me warmer. I admit I will forgo the science and just do what has always worked. But then, I am old and set in my ways.
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