[pct-l] sleeping bags

[Greg Kesselring]

another way I like to look at it is this:  If you bend a fiber and then 
unbend it, how much damage will there be to the fiber?  Maybe none.  But 
if you bend it in an extreme way--for example, creasing it--how much 
damage will there be?  Probably some damage.  Keep creasing it in the 
same place again and again, and eventually the fiber will break.  This 
is what we do when we want to tear a piece of paper--crease it along a 
line, then crease it in the other direction, do this a couple of times 
and the fibers that hold the paper together break, and you get a clean tear.

Using a compression stuff sack puts all the fibers in the down under 
extreme pressure.  It will be like creasing those fibers that are bent 
in an extreme way, resulting in damage to those fibers.  Down is 
extremely resilient, but it will wear out eventually.  IMO a compression 
stuff sack will only accelerate that process. 

Greg

Steel-Eye wrote:
> Good afternoon, Neil,
>
> In my opinion, compression sacks not only add cost and weight, and require
> time to use, but the repeated compression of down is damaging to its loft.
> One noted writer of PCT hiking, and an ultra-lite guru, states that the
> first compression of a new sleeping bag causes a loss of 18% of loft, and
> each subsequent compression reduces loft by an additional 3%.    Based upon
> that algorithm a new bag with 5.00" of loft would be reduced to 0.20" of
> loft at the end of 100 days .. a fairly quick PCT hike .. and would be
> further reduced to 0.04" thick after 150 days.  I think that's total
> baloney, but I can't prove it.  Suffice it to say that compressing will
> cause undesirable and unnecessary damage.
>
> I never compress my sleeping bags, nor even sack-stuff them. I just poke
> them loose in whatever space remains in the pack, and doing so doesn't take
> long.  As a result, my pack usually looks full regardless of the consumables
> I have on board at the time.
>
> Steel-Eye
>
>
>
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