Sleeping bag -- too good to be true?

[Kevin]

http://www.moosineer.com/moosedetail.asp?ID=316

For $80, I'll eat the 7.5 lbs... but is this too good to be true? I'd be fine if I got -10F for the price .

[redhawk]

http://www.moosineer.com/moosedetail.asp?ID=316

For $80, I'll eat the 7.5 lbs... but is this too good to be true? I'd be fine if I got -10F for the price .

Well, I couldn't find any negative reports on the bag.

Of course, I couldn't find any positive ones either.

I still prefer a 0 degree or 5 degree bag, and take a liner and a cover or bivy for the extremes. That way I only carry the extra weight when I need it.

[Rick]

Kevin - Save your money.
For all intents and purposes. The fill material in that bag, if not Hollofil II, is comparable and perhaps not even near the quality of Hollofil II.

Here's a quick rundown of fill materials. I am going from memory of working in a gear shop years ago, so if anybody has additional or more refined info, please add or correct.

FWIW,
Dupont Hollofil 808 is the forerunner of Hollofil II and is an ancient (in terms of camping gear) single hollow core fiber - Think of a very small tube -Traps air inside - The more you can trap air, the better the insulation - The hollow core allowed it to loft a little better than standard solid core fibers that were even bulkier and heavier. I think Hollofil 808 came of age in the late 60's or early 70's.

The next big event was Hollofil II - This is a 4 hole fiber (think of a tube with 4 holes or chambers that extend from end to end.) This offered more trapped air in each strand and even better lofting. This was around the late 70's IIRC.

Next was Qualofil - in the early 80's. This took Hollofil one step further as it was a strand with 7 holes running from end to end. More trapped air, lighter material and better lofting.

Around this time (Late 70's early 80's IIRC) Hoechst of Germany (My old predecessor company) came out with Polarguard (Then 3-D, then Delta) which was a competitor of Dupont.

Dupont's next step in the early 90's was Microloft which was a fine polyester fiber (thinner than human hair strands) that was lighter and supposedly would loft better. This was my first foray from Down into Synthetics - I got a 20d bag in 91 as a pro-deal and had it for 2 years before returning it - I got cold at 45 degrees - The rep said that they were replacing a lot of these bags as the material lost much loft withing a year or two. Around the same time - 3M entered the picture with Thinsulate Lite-Loft - I beleive this had around the same track record as Dupont's Microloft.

I beleive Dupont then developed Thermax - But I don't know if or how it performs in sleeping bags.


The big problem with these bags - Especially the older generation fills - They are to heavy to be effective or efficient for long. Like a classic aerodynamics fuel/efficiency struggle - (The farther you fly, the more fuel you need, the more fuel you need causing a heavier plane requiring even more fuel.....)
With these lower end insluations The more insulation, the more loft you should get in theory, but in practice, because the fill is so heavy, you lose some loft... At some point you cannot just keep adding fill material without collapsing all loft

Also, the loft will likely go flat or get flatter (if not already) within a short period of time - Meaning that perhaps next year it is a minus 15 bag and in 2 years a 7.5 lb zero bag. That's a lot of weight to carry.

Finally, keep in mind that the hollofil series DO NOT STUFF well at all. It might take your whole backpack to fit this thing in - The article mentions 17x12 that's a pretty big package - Especially if it is the smallest it could possible be stuffed. How small can you get it when it is zero or below out and you are cold and trying to pack up....? The Siliconization of the fill might help it loft a little better, but I can't comment to that, as I don;t know.

Now, let's talk construction. The ad doesn't mention offset seams - You want this in a -30 degree bag. It might not matter as much in a 30 degree bag, but in a minus 30, you will end up with cold spots. I am sure that if the seams were offset, it would mention this as a feature & benefit. ( I just relooked - The website mentions offset seams in another section, but I don't know if it applies to this bag)

The other bit you might want to look for is a differential cut in the bag. This means the inside "bag" is smaller than the outside "bag". Get it? Bag in a bag construction.
This ensures you can't depress loft by if you fill the inner bag by wearing more clothes, being a big person or moving around at night with elbows and knees.
Again, this is a nice feature and definitely something you want in a minus 30 bag.

Kevin, I hate to be so critical, but save your money and get a better bag. In two years you'll be looking at this thing and wishing you hadn't blown $80

Cheers
Rick

[redhawk]

Damn! I wish I'd said that!

Thanks Rick. Thats a great tutorial on sleeping bag engineering.

And A great explanation as to why not to buy it!!

Guess it shows why the ADKforum is the place to go with the questions.

(Ungratuitous bit of butt kissing for future considerations!)

Hawk

[Kevin]

Rick, that was 101% useful!!!!

Precisely why I asked... I'm obviously on the market right now for a decent sub-zero bag for this winter. As good as my 25 down EMS bag is, even with a fleece liner I'm not getting more than 10F comfortably out of it, and that's with high quality long underwear on...

I figured if I looked now in the off-season I may save a few dollars. I can't afford more than $200, and most decent sub zero bags I've seen are $250+.

[sacco]

kevin, i'm making my own 0 degree down bag right now.

incase you're intrested, here is the link, with pretty detailed instructions:

http://www.thru-hiker.com/workshop.asp?subcat=5&cid=6

[lumberzac]

Kevin,
Like Redhawk said try using a liner and outer bag. This past winter I went on my first winter backpack and I carried two sleeping bags, my 40*F summer bag and my older 15*F (I think) bag, and an emergency bivy that I bought from campmor for about $20. The total weight was heavy probably around 5lb. The last night out the temperatures dropped to at least -26*F and I didn't feel a chill wearing a long underwear bottom and top. Now if I had a good 0*F down bag, liner, and used the same bivy I probably could have cut the weight in half.

[Kevin]

While I found that to be a really interesting, it's beyond my patience and effort!

I'm one of those people that spend the money for someone else to make it, but I'll complain about it all the way.

[Kevin]

Kevin,
Like Redhawk said try using a liner and outer bag. This past winter I went on my first winter backpack and I carried two sleeping bags, my 40*F summer bag and my older 15*F (I think) bag, and an emergency bivy that I bought from campmor for about $20. The total weight was heavy probably around 5lb. The last night out the temperatures dropped to at least -26*F and I didn't feel a chill wearing a long underwear bottom and top. Now if I had a good 0*F down bag, liner, and used the same bivy I probably could have cut the weight in half.

I'm definitely considering doing something like this, BUT if the combo is not sufficient it could be a matter of extreme discomfort or even death, so I am willing to pay if it ensures comfort and survival.

If I'm going to trust a combination it will have to exactly match what others have used under similar conditions.

[lumberzac]

Almost forgot. A good self-inflating full-length pad makes a big difference.

[Kevin]

Almost forgot. A good self-inflating full-length pad makes a big difference.

I've had that covered since early this year. It's one of the best investments I've made too...

[lumberzac]

I'm definitely considering doing something like this, BUT if the combo is not sufficient it could be a matter of extreme discomfort or even death, so I am willing to pay if it ensures comfort and survival.

If I'm going to trust a combination it will have to exactly match what others have used under similar conditions.

I didn't mean that to come out as just trying to save weight and losing comfort. I meant it to mean more that the use of a good down bag and liner can do the same job that the two synthetic bags could do.

[sacco]

i would definetely go with a quality down bag.

it's well known that nothing compresses as well - so it packs up the best.

nothing decompresses as well - to give you more warmth.

nothing with last as long - saving you money over time.

the only argument against down is when it gets wet, yada, yada, yada.

well guess what ?

all those wonderful new synthetics lose most of their loft too!

besides - how many people here have actually spent the night in a soaking wet sleeping bag?

so my advice is to get the best down bag you can afford and like zac says, use a fleece or silk liner (or both) for added warmth.

p.s. and maybe a waterproof silnylon bag to "double bag it" so everything stays dry for sure.

[lumberzac]

besides - how many people here have actually spent the night in a soaking wet sleeping bag?[/B]

I did once which is why I never carry a camelback brand hydration unit. Nearly 3 liters of water soaked into my synthetic bag. Temperatures dropped to the mid to high 30's that night, but the bag did keep me warm. By morning the bag was mostly dry. But this was the only time I ever had to sleep in a sleeping bag that was soaking wet.

[redhawk]

I was in a 5 degree bag, with a silk liner (the warmest) and a gore tex bivy, inside a single wall two man tent, wearing polypro thermal top and bottom, insulate arctic pants liner and a quilted fleece inner layer in the Badlands, SD in -25 degree temp with winds of 15-25 mph. I also wore a micro fleece balaclava. I had self inflating stearns sleeping pad inside the sleeping bag and a contractors size plastic trash bag under the bag as a vapor barrier.

I was as snug as the proverbial bug in rug (a very warm rug).

When I was in South Dakota I did a lot of winter camping in the Badlands, The Black Hills and out on the Rez. I found the "three layer system" to be the most efficient along with the proper clothing (which i carried in winter anyway). If I had a bag that was rated to say -20, if the temp was above 0 the bag would cause me to sweat, which can be even more dangerous. Just as with clothing, layers allow you to regulate the heat much better and be safe AND comfortable.

It also makes the bag much more versatile. And in the spring, fall, and summer you can use just the liner, or the liner bivy/cover combination. Betwen the three, you should be covered for any weather/temperature.