WM bag overfill – any reason not to?

My thighs always get cold. Unlike my down jacket, I simply don't own puffy pants for sleeping in. I had the extra fill put in the thigh area. I love the bag.
It was well worth the extra weight to keep my thighs warm.

"interesting that so many folks are adding down to the summerlite … while its marketed as a 32F bag, it en-tests at ~35F for men"
If I look to the specs. that's no surprise. For a 32°F rated bag, I always count a minimum of 12,3 oz as necessary. This may be more then many assume, but automatically adds a margin and some compensation.

Alright folks, many thanks for your inputs. I'm taking the Kodiak with me to SJC tomorrow and will drop it off for overfill. That's the bag that I really feel needs the extra down given its oversized dimensions. I'm about to put the Alpinlite through a no-heat dryer cycle to see if that has any difference in the loft. I'll report back on WM's customer service in the next couple of weeks.

I sent my Megalite (short) back for overfill last year, and it was warm enough for even the highest altitude campsites on the JMT in late August. I think it let me comfortably use a 30F rated bag where I normally needed a 20F bag (cold, cold sleeper here!).

I agree with Justin b, a few more ounces on the summerlite would bring it to pretty close to real 3 season temps, ie, 35 or so. Someone described it as 'a little limp', I agree with that, that means it's not overfilled, ie, it has room for more down, so I don't think you'd get the compression issue jerry mentions. With that said, I really like the bag, with wool socks and something to cover the head it's really good in the 40s, which is really 3 season temps where I go/have gone.

I have two wm bags and my only complaint about them is how they rate the temp, I wish that all bag companies would show the full en ratings of the bag, wm shows I think the mid or lower range. If you get the full range, and know where your own body heat generator actually lies on that range, you can actually compare bags. I consider the summerlite a true 40 degree bag, that I could use without dying to 32.

It's tempting to go for the 2oz overfill, I think that would probably bring it to much closer to its claimed temp rating, with basically zero negative impact. Carrying food to generate that extra warmth weighs a LOT more than 2oz.

Note that the highlite doesn't matter in any overstuff discussion, since it has sewn through baffles, which means you have a thin layer of nylon forming cold lines, so no matter how stuffed that is, it's still going to have cold lines on it. I consider that a 50 degree bag, at best, and even at 50 I found it not warm.

So here's my limited take on overfill…

I got my first down bag in 1975, and by 1982 got my first bag with overfill. That bag was a Marmot Mountain Ptarmigan (the actual, Boulder USA made Marmot). I got, IIRC, 2oz's overfill. I went all over the world with with that bag and it served me admirably. In 1992 I sold it (it was still very serviceable) and bought my first Western Mountaineering bag. I got the overfill option in that bag too.

Subsequently I've owned an additional 5 Western bags, and have gotten overfill in each and every one. Currently my wife has an Alpinlite with overfill, and me a Versalite with overfill.

A long time ago, the raison d'etre for overfill wasn't so much about adding warmth as it was about extending the life of the bag. Apparently the added down does help maintain the bags original rating and helps limit deterioration/wear. Sounds moderately mystical, but I do believe it to be the case, and have chatted with the owner of WM about it, and that's his take. Since he makes them, that's good enough for me.

FYI, Hermit's Hut includes free overfill with every WM bag… that's where I've gotten all mine, going back 23 years.

Personally I'd not go to the bother and expense to send a bag back for the treatment, but I wouldn't NOT add the option ordering a new bag…

Best,

Brad

"Note that the highlite doesn't matter in any overstuff discussion, since it has sewn through baffles, which means you have a thin layer of nylon forming cold lines, so no matter how stuffed that is, it's still going to have cold lines on it. I consider that a 50 degree bag, at best, and even at 50 I found it not warm."

Your experience may well apply to a segment of the user community, but the variation is considerable. I used a Highlite for several years in my mid 60's for temps in the mid 30's-low 40's, typical Sierra summer weather. Once I even had it down to 19 degrees when I got caught out in a September cold snap. I had to wear every piece of clothing I had, but made it thru the night, uncomfortably to be sure, but without starting a fire. That said, I considered that experience as a warning and switched to a Summerlite, which worked well out of the box for several year. Then, as I aged and became more susceptible to low temperatures, I sent it back for 2 oz. of overfill, and have been fine ever since. People vary considerably in their tolerance for cold weather, both by individual and more generally by gender. I once lent a WM Apache, rated at 15 degrees, to a very fit lady I backpacked with occasionally for a summer Sierra trip. She froze her a$$ off, whereas I had found it to be far too warm for me.
And she had more body fat than this skinny little weasel. Go figure.

WM's customer service is first class, BTW.

I sent my Megalite 30 F. bag back to WM for an overfill. IT came back looking like Bibendum, the Michelien Man.

I did it B/C I had a few nights in the mid 20 F. range where I had to put on every bit of clothing to sleep well.

Now I'm going to use this bag with a down over-quilt for winter camping and leave my heavy synthetic MH bag at home.
I'll just make a down collar for the Megalite and attach it with Velcro sewn on collar and bag. Off it comes for 3 season camping.

I dropped off my Kodiak on Monday morning and had a phone call the next afternoon to let me know it was ready to be picked up. Super fast, and from my quick inspection in my hotel room, a very neat job. I'll see about weighing it when I get home tomorrow.

Next up, I'm taking my wife's Ultralite in. That's only 2oz, but in a short bag should make a noticeable difference.

Nice one Stuart.

I flew back in to San Jose on Tuesday afternoon for work, made a beeline for WM and dropped off two more bags for overfill. Forty eight hours later I picked up my newly rejuvenated Alpinlite and my wife's extra puffy Ultralite. I'm really impressed at the fast turnaround and such a neat job.

I was also given a sneak peek at the new addition to the Extremelite range – a 14oz quilt / bag liner with 6.5oz down and a full length zip. The Everlite is rated to 45F on its own, or should add 10-15F as a bag liner or overbag. They had just made their first run of 10. It's not quite warm enough for me to use as a quilt in summer, but I could see lowlanders using it quite successfully. Typical WM quality. Nice to see them extending their product line.

The quilt sounds interesting can't wait to see it once it on the market for sale. That's a fast turnaround time for sure that's awesome that WM offers that option.

Have you had a chance to weigh the newly filled bags?

Derek

Derek – after 3oz overfill my 6' Alpinlite comes in at 2lb 4.7oz on my scales. I have a note of the original weight somewhere and I believe it was right around 2lb 1oz. I haven't weighed my wife's 5'6" Ultralite with +2oz or my 6'6" Kodiak with +4oz but I'll do that soon.

They explained to me how they open the bag up to add overfill, undoing the stitching about 1.5" either side of a boxwall divider, adding a predetermined amount to each chamber, skipping the next divider, and repeating. The replacement stitching lines up with the original holes in most cases.

I think that by mail they offer something like a two week turnaround although I'm not sure if that includes transit time. I was really impressed that they were willing to let me come in off the street and drop off my bags with a 48 hour turnaround.

Here's a pic of the Everlite opened up flat that I was permitted to take:

When I got my WM Puma bag in 2005 it was rated at a comfortable -15F. Excellent. Now the same bag with the same amount of down is rated at -25F in their company specs. It magically increased in loft and warmth, I guess. WM stands for Western Magic.