
Ultimate Gnarl Bag
December 8, 2009
Hi Andy, I thought I’d at least send you an email since I just noticed your comments about ripping up a sleeping bag to make one for alpine awesomeness.
I’m in the same boat but further a stern, looking at light bags for summer alpine and rock but wanting to do away with the bivy if I can, maybe just rely on a light tarp and my bags cover. I was wondering what you thought of that, how light is it possible to go in the summer but still have some protection if a storm moves in overnight for a few hours?
Anyways thanks, I enjoy the blog and look forward to your peg book.
Just thought I’d ask,
Cheers, Bob
Hi Bob
The bag I’m messing with is a Wiggy’s Super Lite I bought a few years ago for a trip to Alaska, which I’ve stripped of its outer shell, zipper and hood, and sewn into a prototype Alpkit Epic bivy bag.
WIggy’s are a strange company, a bit of a maverick in the outdoor gear world (jerry Wigglow’s rants are well worth seeking out on their website for their anti gear establishment views). I was recommended their bags by the ultra hardcore dog sledder Gary Rolfe, who’d used them in some very tough conditions, and I even popped into their factory in Grand Junction to check them out while driving from Boulder to Salt Lake (which is further than I’d imagined). The bags themselves have a continuous synthetic filament, making them super robust, and the bags themselves look like they’re designed for a hunting/military user, having just about the heaviest weight zippers and shell fabrics you’d find outside of the leisure camping market.
I bought the super light bag, which wasn’t that super light (1.8kg) but did have a comfort rating of -20C. I’m always sceptical about temperature ratings, but the Ruth gorge in March put it to the test and it passed with flying colours (Paul Ramsden had a Rab 650 gram bag, a North Face insulated bivy bag and he was still cold). I also bought a Wiggy’s overbag - and kind of oversized sleeping - that fitted over the Super Light for really cold conditions. In the end, Paul had to use the over bag as well, and I just slept in the Super Light!
One thing about the bag was its bulk, which obviously was being converted into warmth. The bag itself was sewn together in a very simple way, which meant there were cold spots at the side seams (in fact there was ice on the seams), so when I got home I decided to make it my project to try and strip it down to the basics (no zipper), and add lighter fabrics.
That was about three years ago, and it’s only been this week that I’ve got round to finishing this long-standing project.
In order to reduce weight further, I thought that having 200+ grams of the outer shell on the bag, plus 300-500 grams of bivy bag, was a waste. And so I sewed up the bag with a lighter (and bright, so it’s easier to find stuff) inner, and then just sewed it into the Epic bivy bag. I also reduced the bulk by having no zipper, and no hood, after all, what’s the point when you’ve got so many hoods already (jacket hood and belay parka hood.
Another few additions were a pocket of material at the foot to help keep my toes warm (your feet are the least well-dressed part of your body if you take off your inner boots), and a drawcord at the waist, to help reduce convection when cooking.
The one thing I’d like to add is some 2-way zippers for use as arm holes for cooking (maybe even belaying!) which was first used on the PHD Zeta bags (and then on the Mountain Hardwear Lamina bags), but my sewing isn’t so great.
When I started I thought I’d just go for a top bag, with no insulation on the bottom, but when it came to it - well I just wimped out and thought I’d make the saving somewhere else. Also having a top bag works well when you can lie down (I’ve been using a Ray Jardine homemade bag/quilt for Kayaking for over a year), but on sitting bivy’s you’d probably be glad of the overall protection.
I haven’t used my bag yet, but I’ll report back when I do.
As for a summer bag Bob, I’d have thought you could go for a similar deal, using a BD Epic bivy bag and one of the Wiggy’s FTRSS Overbags, which I think with some clever sewing could yield a .500 gram summer alpine bag (that is if you’re not a wimp like me and just make it a top bag).

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