Delta discontinued ?

Nope, it’s still around.

They are introducing a new, “more” durable, and slightly heavier product called Climashield.

Delta’s durability issues occur in the thinnest versions of their insulation, which have been discontinued. They are still producing Delta in 2.7 osy weights and higher, and for their extra special customers :) 2.0 osy, which is what is used in Cocoons. They are not producing anything less than 2.0 anymore.

Ryan, do you know anything about this Climashield? I know it’s a continuous filament insulation made by Western Nonwovens and that it should come in 2,7 and 5,4 weights but that’s all I could find. Any idea how it compares to Delta ?

they sell it at thru-hiker.com

the 2.7 weight is .75-1.0 inch loft

Thanks, Ryan, I’m also curious about Climashield. If Richard Nisley’s calculations are correct, Delta has a clo value of 1.467/oz. and 3D has .909/oz. If Climashield has a clo value of only .68/oz., what else does it have going for it? Is it much more durable? Cheaper? More compressible?

What exactly is the durability problem with PG Delta? Does it lose substantial loft once you compress it?

I think that is the claim. Here’s something I found at Ray Jardine’s site:

http://www.ray-way.com/quilt/delta.shtml

Take it for what it’s worth. I also found a post at the TLB forums dated 11/25/05 by thru-hiker.com’s AYCE titled “Polarguard Delta has been discontinued”. AYCE seems like a reasonable guy with no particular axe to grind. He doesn’t really get into it but cites “..production and durability issues especially with the 60g weight”.
Since Ryan works with the manufacturers, I’ve sure he’ll be able to shed more light on this.

Thanks, Dondo.

Jardine claims only a fraction of an ounce difference in weight of a bag made from PG-Delta vs. PG-3D, but Fanatic Fringe has two 40-degree quilts: they claim the one with Delta to be 2.5 oz lighter than the one with 3D. The 8% decrease in quilt weight isn’t huge, but I think many here would consider it worth the additional $30. But, if Delta is going to lose considerably more loft than 3D, the small weight savings may ultimately translate into a colder quilt.

I saw on another thread that BPL is working on an article about insulation. Jardine’s claim that it’s all about loft–regardless of the material used–doesn’t seem quit right. As I recall, the folks at 3M claim, in promoting Thinsulate, that it’s also a matter of how many tiny compartments of dead air are created by the fill.

Bill

William,

My understanding is that while loft is important, it’s really all about clo. AYCE over at thru-hiker.com discusses clo and clo values in several threads on his message board. To further complicate things, I’ve read that the scientists with the copper mannequin at Kansas State abused a short-staple fill bag(LiteLoft?)to the point where it had lost 27% of it’s original loft. When they tested it they found that it retained 94% of it’s original insulating ability. That would seem to support the tiny compartments theory. There seems to be a lot to learn about the subject and I’ll be looking foward to reading the upcoming BPL article.

Totally agree. A lot to learn. Can’t wait to be educated by BPL.

Richard seems to have a pretty good handle on the subject. Perhaps he will author a lengthy Primer in the form of a Forum post? Please, Richard, say ‘Yes’.

I’ve never had a thinsulate jacket (and I still have two older ones) that were as warm as a more “poofy” synth or down jackets – even with all having the same lower temp ratings.

I’ve also been quite perplexed by Sleeping Bag Mfrs using the same number of INCHES of LOFT for a given similar lower temp rating for both their down and synth offerings. The weights are different, but the lofts are the same, whether it’s a 20deg down bag or their 20deg synth bag. How can this be if one traps more air than another? Or does down trap more air than synth? My gut says yes, but my gut’s been wrong a number of times before. Richard, any help here with this one?

Paul,

You bring up another vast and interesting topic. How do manufacturers choose temperature ratings for their sleeping bags? It must be tough. After all we are all different physiologically and psychologically. Some sleep on thermally efficient pads inside true double wall tents. Others choose tarps and minimal pads. Add factors of how tired you are, how well fed, and how acclimated to the cold. Throw in weather related factors such as humidity and wind speed.
We’ve all had to rely on anecdotal evidence on how various manufacturers rate their bags. Company x uses very conservative ratings;company y’s ratings are wildly optimistic. Some of us bring rulers to the store to measure loft and carefully inspect efficiency of fit, hoods, draft baffles and collars.
Europeans are on to a better way of doing things,IMO. They’ve adopted a standardized rating system,EN 13537, based on testing bags using copper manikins. Though the system not perfect, even it’s fiercest critics agree that having an objective standard is better than having no standard. The tests produce four temperature results, two of which I find the most useful. The “comfort” temperature is based on a “standard” 60kg woman having a comfortable night. The “lower limit” is based on a “standard” 80kg man sleeping comfortably. Once we figure out where we stand in relation the the standard, we’re more able to choose a bag that will be right for us.

Dondo,
American manufacturers rejected efforts to create a rating system using a copper manikin back in the 1980s (if I remember correctly). There were several reasons, cost and questionable reliability (which was to be expected in a new technology). The real reason, I am given to understand, was that a couple of big names were unpleasantly surprised by ratings of their stuff.

The same folks who use the following terms object to objective ratings. I’m sure you know exactly what is meant by such terms as lightweight, technical, professional, durable, performance (and high performance), waterproof, water repellant, windproof, three-season, two-man.

Vick,

I think I hear what you’re saying, so I’m not holding my breath for objectve standards to be adopted in the U.S. any time soon. Kansas State textiles professor Elizabeth McCullough has been trying to get something going for a while and it doesn’t seem that she has made much headway. To their credit, EMS and MEC have submitted sleeping bags to Kansas State for testing.

I feel temperature ratings are essentially useless. When I worked in the outdoor industry back in the 80’s, a friend who was the regional sales rep for the old Marmot Mountain Works (now Marmot) told me that the salesmen got together and decided what the temperature ratings would be for their bags at their sales meetings.
There are too many variables as mentioned earlier to be able to predict temperature ratings. I had a talk with Dr McCullough back around 85′ about doing some testing of sleeping bags for our company but the expense was too great. The environmental chamber at KSU could be useful for measuring heat loss and therefore how efficient a garment or bag would be; but as far as being able to accurately predict temperature ratings; I do not think is possible.

I have a real interest in this area.

So, I’ll volunteer to be the test dummy (i should be emminently qualified – both from experience gained currently working in a Test Engineering organization and being a dummy).

Hmmm…So it looks like the options are:

A. Adopt a system similar to that adopted by the European Outdoor Group involving independent testing of sleeping bags on copper manikins inside climate controlled chambers.

B. Have the sales reps in the individual companies make up the numbers over coffee and donuts.

C. Since ratings are essentially meaningless, let’s do away with them altogether.

D. Mail your sleeping bags to Paul Johnson. He’ll get back to you.