Assessing the future lifespan of a 40 year old down sleeping bag (TNF Ibex)

About the only thing I could offer is that you could measure the loft if the seller laid it out and gave it plenty of time to fluff up. This would give you some idea of its present insulation value but that would not tell you what to expect for the rest of its life expectancy. I would also wonder what the fabric and also thread life of a piece of gear that old would be. It may be less than down depending on storage temps. Just thinking out loud here.

Good luck.

Dear Greg,

I am going to go a bit off topic here. And I am going to recommend not buying it, regardless of its usability and bargain price. I just got into winter camping. I have done two trips so far, so I am a newbie. One last year and one this year, both at the Perch campsites. Temperatures were -5 & 0 according to the forecast (I actually did not verify this, but they probably stayed in that ballpark). Slept on a single skin tent on a  3/4 Ridgerest and a Regular NeoAir Xlite the first night and the 3/4 Ridgerest and Klymit Insulated Static Vlite the second.

When considering purchasing a zero bag for my trips, I saw that they weight around 3#s, more or less for an 800 fill one. On those trips I slept warm wearing midweight thermals inside my 15 Montbell and my 40 EE Revelation, both 800 fill. I didn’t have to wear any of my additional insulating clothing. I was very warm, no cold spots. I bought the quilt with the idea of using it for both summer and also this purpose, so I sized up in both length and width, so I could drape it over my Montbell sleeping bag. I am super happy with this setup, to the point that I don’t regret passing an incredible deal a couple of years back for a 0 degree bag for under $200 new with 800 fill. I don’t have to store this extra bag at home, and I feel the $200 are better invested somewhere else. So that is why I recommended not purchasing this bargain, as at the time I was a little torn, but now in hindsight I don’t regret passing on my opportunity for that bargain.

I also want to add that I sleep warm, at least compared to my two regular camping companions. How warm? No scientific test for that. But let’s say that I find EN comfort ratings accurate for me sleeping in the intended midweight top and bottom thermals. On those two winter nights, I also placed a 1 liter Nalgene HDPE bottle inside an EMS insulating sleeve at my feet. The water was still warm in the morning.

You have probably heard references to layering bags before on several occasions, so I am not saying anything new… Some people will recommend going with a synthetic quilt to layer on top of the down as a better option, and at 40 degrees, both down and synthetic are rather close in weight. But again, I am a newbie, and I am certain other much more experience campers and mountaineers can share their experiences as well as to the need for a zero degree bag or not. Also consider, that what works for some of us, won’t work for others. Take what I am saying with a grain of salt if you are a cold sleeper.

Finally, if weight and cost are a concern, and since you don’t mind lightly used gear, I sometimes see 0 degree 800+ fill quilts on sale for about $200, which paired with a down or synthetic hood would get you to that temperature rating for well under 2#s.

Now for my next winter camping trip, planning to do it within the next month, I want to try staying in a hammock. I camp in a hammock often in the three seasons, but this will be my first winter hang. It seems like it will be sooooo much easier than tenting :D I have sold my North Face Assault 2, current model. It seemed like a great tent, but it was too short even on the diagonal to accommodate my 5’10” frame, when on top of two pads and the bulk of the two bags, which were touching the walls, and therefore collecting significant condensation (not a big deal for a one nighter, but three may have been a problem…?)

Best of luck!

jimmy–good call on measuring current loft and comparing it to known ratings. Thanks as well for the reminder that fabrics and thread might not be as long-lived.

iago–thanks for taking the time to give such a thorough and helpful narrative based on your experience. While many winter trips with the AMC (I took their winter course last year) require a bag that’s 10-20 below 0, I think my next few winter trips will more likely be with experienced friends which gives me more latitude to experiment with a bag combo. I remember Philip Werner of Sectionhiker, who gets out a lot in the Whites in winter, saying he’d sold his -20F bag because he tended to cancel trips anyway if the forecast was going to be that cold. Your thoughts about not having an extra bag at home that gets little use resonate with me too. Much appreciated. Hoping you do a trip report for your winter hammock trip!

Greg,

Today’s bag ratings are more conservative than what was used even 20 years ago, so keep that in mind.

LIke iago, I find the two bag 0 degree/40 degree system to be very versatle, and has worked well for many trips. There are many experienced users here in BPL which point to a two bag system to be inherently BETTER than a single bag at a similar loft (putting weight aside), for cold weather trips.

I got my NF Ibex in 1976. I lived in New England at the time and used it on winter trips, including winter climbs in the White’s (Presidental’s). I found the temp rating to be slightly optimistic, but it was certainly an adequate bag for the conditions I used it in. I believe -15* was the coldest I used it. It doesn’t have a draft collar, something fairly rare then.

It would not be my 1st or even 12th choice today. I think a draft collar is critical on a winter bag. 550 ci down was the norm in that era before Chinese and Eastern European down became widely available, hence more weight of down was used to achieve its temp rating relative to today’s bags. I really couldn’t remark on its current loft without seeing it. Undoubtedly it’s lost a bit, but how much would be hard to say from 2,000 miles away!

Personally, I think you’re throwing good money after bad. Shop sales, and find a decent -10* to -20* bag. Or, use less warm bag and use an inner or overbag.

Regardless, get a bag with a draft collar. That’s my advice.

Thanks Matt and Brad. Sounds like there is consensus. A good friend and hiking buddy of mine who works at a backpacking shop also agrees. I was tempted by the possibility of lowering weight and (especially) bulk, but it sounds like this bag is not the way to do it.

Again, thanks all for taking the time to share your experiences with me.

Down does not degrade from just being old. But, 40 years ago, they were not real fussy about what type of down or fill power.

While the down is still good, I would look at the shell and stitching and zipper. If the shell is nylon, it night be fine. If the threading is poly it is likely fine. Both are plastics and do not degrade easily if not exposed to UV. Cotton thread is a bit worrisome, if was at all damp, both the down and the threads will show some degradation. Check the threads, if they are going bad, assume the down is too. As was said, it is likely NOT a -15 bag by today’s standards. I expect more like -5. Especially with no draft collar.

If you can get it for considerably less than the cost of a 600fp -15 bag, and it checks out, it might be worth it. Otherwise just save your money for a better bag.

A flamingo in Adelaide died in 2014 at the age of 83.

Thaao, a Andean condor died at age 80.

A Cockatoo in Illinois was verified as 83 years old.

A 66-year-old albatross laid an egg at Midway Atoll last December.

Sounds like your bag has another 40 years left.

Another vote for skip the deal. Down quality and features are deciding factors.

Down should not degrade that much, but really depends on the actual fill. I have an Eddie Bauer canvas down bag, made in Seattle that is >40 years old. States on the tag 90+% down, but not all bags made then were that much. 3lbs of down, quite warm, but heavy and not as lofty as my 10 degree FF bag. Lesser quality fill back then will be even worse today.

Features are key. Really look at the draft tubed at the zipper and your shoulders, hood shape and fill, foot box fill, and down distribution top to bottom.

My EB bag is for my dogs, turned inside out so they lay on the canvas. Great for them, would not rely on it myself.

Regarding your area, I camped in the Whites the past few years. Winter weather there is a bit more unpredictable, especially in higher elevations, than most places I have been. If I was relying on the bag only, not sure -15 is enough. If you have a solid winter pad (I use the exped downmat winterlite) and some down garments to boost the rating, probably ok.