A place to chat about gear and the philosphy of ultralight. Ultralight bushwalking or backpacking focuses on carrying the lightest and simplest kit. There is still a good focus on safety and skill.
Forum rules
Ultralight Bushwalking/backpacking is about more than just gear lists. Ultralight walkers carefully consider gear based on the environment they are entering, the weather forecast, their own skill, other people in the group. Gear and systems are tested and tweaked. If you are new to this area then welcome - Please remember that although the same ultralight philosophy can be used in all environments that the specific gear and skill required will vary greatly. It is very dangerous to assume that you can just copy someone else's gear list, but you are encouraged to ask questions, learn and start reducing the pack weight and enjoying the freedom that comes.
Common words Base pack backpacking the mass of the backpack and the gear inside - not including consumables such as food, water and fuel light backpacking base weight less than 9.1kg ultralight backpacking base weight less than 4.5kg super-ultralight backpacking base weight less than 2.3kg extreme-ultralight backpacking base weight less than 1.4kg
This is the new award-winning Yeti Fever Zero sleeping bag, which weighs just 280g and is, says the brand, the world's lightest sleeping bag - the previous holder of that title was also made by Yeti and was a colossal 40g heavier at 320g... http://www.outdoorsmagic.com/gear-blog/ ... 11492.html
Kinda pointless isnt it? At a 15c comfort rating why wouldn't i just sleep in my clothes which would also keep me warm at those sort of temperatures. That would save me a whole 280g!
For the dimensions it's pretty light on down. I had a quilt that was 50" wide tapering to 36" @ the foot end with sewn through construction, that had a similar amount of fill to this (5oz 800 fill). Very little loft, around 15mm maybe at the center of each baffle. Great warm weather quilt but it was purely summer only.
Good to see the envelope being pushed. I have to laugh at the image for the bag though. Looks fit to burst with loft...... From my experience with similar fill on a smaller quilt, IMO the one in the image looks to be overstuffed to make it look extra puffy. In real life I don't think that would be the case.
wayno, you seem to stay abreast of the lastest gear. Has anyone proposed an inflatable, baffled top quilt? It could be like a Neoair except made out of less durable material since it wouldn't have to support your weight or be as resistant to puncture. Maybe it could even be filled with argon?
There was, years ago, a sort of sleeping bag bivy combo that used air beams. But it was heavy even for the intended temperature. I'll see if I can remember a key word of sort to find it on Google.
The fabric of the new Yeti bag is 20g for a square meter. Hard to do that with a somewhat puncture resistant material.
Orion wrote:wayno, you seem to stay abreast of the lastest gear. Has anyone proposed an inflatable, baffled top quilt? It could be like a Neoair except made out of less durable material since it wouldn't have to support your weight or be as resistant to puncture. Maybe it could even be filled with argon?
ferrino of Italy showed some inflatable sleep systems at Friedrichshafen show 1 or 2 years back. Not sure if they were adopted/commercialised, all I could see just now was the integrated bag/sleep mat, but sniff them out perhaps?
Orion wrote:wayno, you seem to stay abreast of the lastest gear. Has anyone proposed an inflatable, baffled top quilt? It could be like a Neoair except made out of less durable material since it wouldn't have to support your weight or be as resistant to puncture. Maybe it could even be filled with argon?
ferrino of Italy showed some inflatable sleep systems at Friedrichshafen show 1 or 2 years back. Not sure if they were adopted/commercialised, all I could see just now was the integrated bag/sleep mat, but sniff them out perhaps?
I have wondered extensively about this.
*The first obvious hurdle is breath ability. If an object is air tight then it won't have any ability to be moisture permeable. So it could be quite sweaty, but potentially very warm. *The next hurdle would be comfort due to the rigidity of the the cocoon/sleepingbag. * Alot of air would be need to inflate the entire cocoon.
My thoughts though about overcoming some of this is for the cocoon the cocoon to be a combination of technologies. The base would be the same as a Neo Air. However, the upper would be a combination of inflated rings and welded to more traditional sleeping bag fabrics. This would ensure the bag maintains loft. The rings would need to have foil inside like a Neo Air. The inflated rings would be end around the foot, the hips and the shoulders.
This is a very complicated way of improving the capacity of down to expand. So I don't think this would be worth it....
However, what if...
The un-inflated sections had foil inside of them in them the same as the inflated pad. Then there might be many benefits in doing it. But you also return to the first hurdle of Breathability due to the foil.
I wonder if the foil would still reflect as much heat if it were perforated with millions of tiny holes??
If you could achieve this then the the other opportunities are enormous. It would be possible to have super light insulated tents. Imagine if the roof and walls of an inner tent were baffled could be baffled a reflective foil liner.
How does the inflateble jacket from Klymit breath? are there panels around the arm pit that are different?
thy are like puffy jackets, its not inflated all over the garment, it broken down to small inflated compartments, you can have the garment breathe in the narrow gaps between the inflated compartments
I think the 280g Yeti corresponds to the L size in PHD, that would make the PHD 260g (more or less) Given that the Yeti fabric is 40% lighter per square meter, I would think that the Yeti has a bit more down inside making it a bit warmer. Both brands claim to be using 900+ down.
Orion wrote:wayno, you seem to stay abreast of the lastest gear. Has anyone proposed an inflatable, baffled top quilt? It could be like a Neoair except made out of less durable material since it wouldn't have to support your weight or be as resistant to puncture. Maybe it could even be filled with argon?
Yes -- The Enlightened Equipment Epiphany. Inflatable cuben fibre quilt. You could adjust the warmth by adjusting the loft!
Tim over at EE keeps saying that he might bring it back. Check out reviews of it here.
iGBH wrote:Kinda pointless isnt it? At a 15c comfort rating why wouldn't i just sleep in my clothes which would also keep me warm at those sort of temperatures. That would save me a whole 280g!
iGBH wrote:Kinda pointless isnt it? At a 15c comfort rating why wouldn't i just sleep in my clothes which would also keep me warm at those sort of temperatures. That would save me a whole 280g!
This makes so much sense!
yeah but ultralighters know that if you sleep in your clothes as well, you'll get a lower comfort temperature out of the bag and they'd factor that in.. plus some ultralighters will really push a bags rating and use it well below its comfort rating, especially if they know they sleep warm....
iGBH wrote:Kinda pointless isnt it? At a 15c comfort rating why wouldn't i just sleep in my clothes which would also keep me warm at those sort of temperatures. That would save me a whole 280g!
This makes so much sense!
yeah but ultralighters know that if you sleep in your clothes as well, you'll get a lower comfort temperature out of the bag and they'd factor that in.. plus some ultralighters will really push a bags rating and use it well below its comfort rating, especially if they know they sleep warm....
Lol wayno I have a feeling Strider was making the same point as you but rather more sarcastically
Cool concept. I hadn't heard about that. It was available in 0.33 oz/yd² (0.11 11 g/m²) and 0.48 oz/yd² (0.17 17 g/m²) Cuben fabric. You have to wonder how puncture resistant they were. Their 4°C rated bag weighed about 380g.
I think I'd rather have soft breathable nylon against my body than a VBL. Just my preference.
edit: ooopsie
Last edited by Orion on Wed 02 Oct, 2013 2:35 am, edited 1 time in total.
Oh, I see. The quilt isn't sealed tight and brand new Cuben has some finite air permeabiity as well. So the inflation can only be sustained to the loft that the down is capable of supporting in the first place.
In terms of sewing the "world's lightest" bag, is the 0.11 g/m² Cuben the lightest down proof fabric available?
Franco wrote:...would you really want Cuben against your skin ?
Orion wrote:I think I'd rather have soft breathable nylon against my body than a VBL. Just my preference.
It's a good point though. It's not really apples to apples if the fabric isn't breathable. I've slept warm enough under an 85g emergency space blanket well below the 15°C rating of the "world's lightest" bag.