Thursday, November 29, 2007

Bag design all-but finished; now to order

I have been running the numbers and have updated the bag design. The top piece will be 20" wide at t, and will taper down to 10". I also completed a hood design, figured out total volume of down (~8800 in^3) and picked up elastic chock cord for the hood and toggles for the same.

All that is left is to figure out what fabrics I'm going to use and where to get them; after that I'll calculate projected weight and sew it all together.

I'll order the tarp material with the sleeping bag materials, so I'll have a couple of projects going at once. The tarp should take an hour or so. All that is required is to hem the edges, sew on the guyline attachments (including reenforcements) and figure out how the ridgeline attachments will work. I still need to get grommets, the appropriate webbing and the Kelty Triptease. That's all for now.

Monday, November 26, 2007

Bag prototype 1 finished

Well, the first design of the bag is finished, sans hood. Because I don't have pictures to show, here's a rough estimate of what it looks like.

The top and bottom are 6-sided shapes and look like someone put the long ends of two trapezoids together. The lower (and larger piece) is 60" high, 24" wide at the top and 12" wide at the bottom. The top trapezoid has a width of 24" at the bottom, 12" at the top and a height of 5".

The bag is about 18" at my hips and is about 5" taller than my height (at my shoulders). The design is styled to wrap around my shoulders. I will be making an insulated jacket-hood for the bag. The sides ares 10" high and ~75" long. They go from the bottom of the long side of the shell around to the top of the smaller trapezoid, leaving a 12" space open for the hood. The footbox piece is a rectangle 10"x 12".

Without the hood, the bag will require ~6600 in^3 of down @ 2.5 inches of insulation. That's approximately 9 oz of 800 fp down. It is also a rating of at least 20 degrees, my goal. According to jardine measurements, it is an effective temp rating of o degrees, which I skeptically view as generous. Anywho, I need the bag to be able to handle sub-freezing temps but I don't expect to take it on a winter expeditions. It is going to be a tough, workhorse 3-season+ bag.

Thursday, November 15, 2007

New hipbelt and food update

I ran through food calculations a few days ago. After determining that I would need 3500-4000 calories per day, I came up with the following daily menu:

2x PopTarts (two packages)
Gorp, mixed 1:1:1:1:1 in 1/4 cup proportions of granola, honey-roasted peanuts, M&M's, honey-nut Cheerios and raisins.
2x Pitas
Peanut butter, 1/2 cup
Honey, 2 tbsp
1x Snickers, currently the 2.07 oz versions
Mac & Cheese, 2/3 box/day
Butter, 2/3 stick/day

That's ~4000 calories/day for about ~2 lbs/day. I'll also be carrying an extra day of Gorp, so the total food weight is just under 21 lbs. Here's a more detailed breakdown. You'll notice that all of the meals are very calorie-dense, as the average cal/oz is over 128 cal/oz.

TOTALS Cal Cal/oz
Cal/day 4097.40
breakfast cal 800.00 108.9918
gorp cal 730.30 135.847
lunch cal 1232.50 117.0465
aft snack cal 280.00 135.2657
supper cal 1054.60 139.4974
cal/hr (24) 170.73
Cal/hr (10) 409.74
oz/day 32.88
lb/day 2.05
total oz 334.13
total lb 20.88
average cal/oz 128.47
extra gorp oz 5.38
extra gorp cal 730.30
Cal/trip 40974

In light of this this food weight, I designed and constructed a hipbelt for my backpack (a sil-nylon frameless rucksack designed by a friend). It was quite simple. The idea was to sew a piece of fabric to the pack between the bottom shoulder strap atachments. The belt would slide into this sleeve and be held in place by 3" velcro strips.

I cut a 4x8 piece of sil nylon and attached the some velcro (loop side) to the patch. I sewed the long sides to the pack in between the hipbelt, with the velcro facing the pack. I then sewed the belt, 3x25 with ~23 inches of foam in it; the portion of the belt facing me is a coated cordura that has a rough face to it. It grabs my hips well. The outer portion is sil nylon (same as pack). The buckle is one with room for four slots of 1" fabric. It is similar to having four ladder lock buckles attached to a side-release buckle.

To test, I placed a blue foam pad in the pack, stuffed a blanket on the bottom and then set eight textbooks, each with at least 800 pages, in the pack. The belt worked well and effectively took weight off of my shoulders. I would like the pack to be a little deeper (may two inches) to create a more effective belt that would allow the weight to rest at the base of my back, but I don't want to remake the pack. That was pain enough in itself.

The sleeping back is on temporary hold until a project or two gets finished.

Thursday, November 8, 2007

How much clothes?

Another issue is clothing. Traditionally, I have carried the following:

[links are to same or similar products]

fleece skullcap
power stretch fleece gloves
Wool shirt (old REI sweater)
wicking shirt
Poly pro top&bottom
Spandex shorts
Pants /w zip off legs
3x liner socks
1x SmartWool medium cushion hiking socks
Precip Jacket
Precip Pants (mid-calf zip)
Keen Targhee II (low top) eVENT boots

Some recent additions are questioning portions of the above.

First, I picked up a Marmot Ion windshirt (5 oz, reasonably breathable) that one amazing piece of gear. It is a size small, one size less than it probably should be, but is is a snug fit moves well. Marmot's website says it is designed to be worn over a base layer or minimal insulation (think 100 or 200 wgt fleece). My testing (running /w base layer top) has confirmed this. The fabric appears water-resistant, but the seams are not sealed. My only test was in a heavy downpour during a 15 bike ride. The sleeves filled with water, but the water stayed there. It must have been leaking in from the seams.

I am going to carry this, even though it is additional weight, because it is annoying to wear a full-on raincoat/hardshell (Marmot Precip jacket) when the wind picks up but there is no rain. In comes the jacket. I have also found that if I do not wear a long-sleeve shirt, the fabric will hug my skin and make my forearms cold. The jacket also stuffs to apple size.

Second, I acquired a 200 wgt polartech fleece vest from REI (on sale for $10, normally $30). It is incredibly soft and sweet. I'm thinking about dropping the wool shirt in favor of this vest. It weighs less and takes up less room in the pack. My only worry is if it will be cold on the forearms at night.

I'm going to say no to that one. I'll be moving during the day, and I generate and retain a lot of body heat, especially if I wear hat/gloves. Wind and/or rain is covered by the marmot coats. At night, I'll be cooking under the tarp, and can lay sleeping bag whilst my dinner cooks.

I'm going to design the sleeping bag this weekend. The first prototype should be done by Sunday sometime. As I said earlier, it will be a snug fit and have a jacket-like hood a-la Sierra Designs bags. example

I'm not sure which insulation I'm going to use. I'd like to go with down on this one, but is is quite a bit more expensive than Climashield XP or Combat. (XP @ 5.0 oz/yd^2 /w 1.2" loft and 0.82 CLO is $13.95 or so per linear yard (36"x60"). I would need at least two yards, maybe four. Down is $25.95/3 oz. Just with rough calculations (36" x 72" x 2" = 5184 in^3)/800 in^3/oz I need at least 6 oz, and I bet I'll need much more than that, at least another 3 oz package.

I'm aiming for about 20 deg F with the bag. I'm making it with no insulation on the bottom (like Big Agnes and Stephenson Warmlite bags) and a full two-way separating zipper. The goal is to keep it under 32 oz (2 lb).

Tarp update - I'm definitely going to go with a tarp, a 5'x9' one at that. I will be bringing the tent (Tarptent Double Rainbow by Henry Shires ) in the car and will take it if the weather looks really nasty for the week. I'll be using 1.1 oz silicon impregnated ripstop nylon. It comes in at ~1.3 oz/yd^2 after the impregnation. The tarp (6.5 oz) /w 6 stakes (2.1 oz), 50' of Kelty Triptease (1 oz), 6 webbing loops ( .5 oz) and a 40" x 72" Tyvek groundsheet (~5?) should come in at about 14-16 oz (it's a guesstimate, mostly on the Tyvek).

I would use the .7 SpinnTex (.88 after impregnation), but it comes in rolls of 54" wide, and I need all of the width I can get. It would save me about 2 oz. I'll take the protection.

I'm going to also make a pot cozy out of close-cell foam. It will weigh may an ounce or two and allow me to get away with two fuel canisters instead of three (4 oz canister, 8 oz of fuel per bottle). I am planning to use the stove only for supper.

I'll try and post some pics of the design this weekend.

Wednesday, November 7, 2007

Upcoming trip

Two trips are planned in upcoming months:

I'm heading to the BWCAW this winter, around the end of December between X-mas and new years, with return new year's day. There are a few considerations to take care of:

We don't know where we're going to go - this includes entry, exit and route. Gear is a slight issue, being having proper shelters, bags and boots. I think the tents are taken care of (old kelty dome tent and REI half dome 2), but I don't trust them completely in winter. A heavy snow storm would really mess things up. I also lack snowshoes, but that is something else to think about.

More importantly, I'm going to solo thru-hike the SHT this May. I'll plan for 15 miles per day and try to do 20. I'm going to plan for 12 days and take try to do it in 10, me thinks.

Base packweight is somewhere around 12 lbs, and a fully-loaded water bag will add about ~5.5. The water weight will not go away, so I'll consider it an average of 2.5ish, so that's 14.5 lbs packweight. I'd like to cut that down to 12ish with water included. Food is heavy, naturally, but I'll be eating a lot per day.

Last May on the SHT, things did not go so well because of the excessive distance, poor conditioning and I believe that pack weight was too high (although it is not much higher than it is now). For the solo hike, some changes are in order.

I'm seriously considering making a 5'x8'+beaks tarp for the SHT thru hike. Such a shelter would by about 5 yd^2 of fabric at ~1.3 oz/yd or 8 oz. Lines, stakes and pullouts might add 6 oz. With a custom-cut tyvek, the shelter could weigh just over a a pound. It would cut two lbs off of my shelter weight. Also, we took a custom tarp/tent shelter last year, and it was floorless. It worked well. However, I have little experience with tarp camping. As much as I love the tarptent Double Rainbow, it is heavy when compared to the tarp. My gut says this is going to be a night-before decision, as bad weather could force me to bring the sturdier shelter.

I'm working on a design for a legitimate sleeping bag, something along the lines of the Sierra Designs bags with the jacket-like hood. In the same vein, the new Thermarest weighs in at 20 oz, and if one throw out the the tent, it is the heaviest single piece of gear in the bag. My blue foamer would weigh in at about 8 oz.

Anywho, I'll publish a full gear list before I head off, with weights, food and trip budget.