Back to Work

The first prototype is basically finished.  Well 90%.  The last 10% is a real pain because I need to make the straps longer and come up with some way to attach them to the pack for testing.  I know how they need to be attached in the future but currently i need to test some variations and it's a bit more work.  Truly this is the critical step in my initial design prototyping.

Getting the pack to this point was full of delays and challenges.  I thought I could be here weeks ago but I had difficulties with the sewing machine that took while to figure out.  Apparently you need a special needle for heavier gauge thread, and that made the machine jam up every time I tried starting a stitch.  Plus the tension was all wrong.  That was frustrating but I now know the machine a lot better.  I first sewed the sides to the front and then to the back.  That part was pretty easy although the curved sections proved to be a pain in the butt.  I know I can find a better way to do that.  Something repeatable, because I sit here and design this, I am totally thinking with an eye towards a small scale production.  If this project goes anywhere, that's where it will end up.  The hip belt was a little difficult getting straight with the whole pack sewn together.  Next time, I will sew that onto the back panel first.  That and the shoulder straps.  It is way too much of a pain sewing those on last.  I like what I did with the straps.  I made a 6 inch long piece of fabric that I sewed on to the pack as an upside down T.  The piece extended 2" off the pack and was angled at just the right angle of my shoulders.  I am not sure where the strap should sit yet, closer to the outside shoulder or closer to the neck, but with the 6" length of my attachment piece, I can vary the strap placement pretty easily.  I would also like to do something like that with the bottom of the shoulder strap but there is too much variation in what I would like to try right now.  That is whats throwing me off right now because I have 4 different ways that I want to take this right now.  I'm not real sure how to do comparison testing without make separate prototypes.  I think I just need to make one model and try it out and then vary the position and try it again.  That will give me a lot of additional data to use as I move forward and make another model.  The hip belt is a real small 1" wide strap that I had lying around.  It works but I'm not sure how well it will do with weight in the pack.  Right now with a sleeping bag and a tent rain fly in it to hold its shape, it is extremely comfortable.

Dimensions

The other day, I think it was Wednesday, I fiddled around with finding out some dimensions for my first prototype.  I mainly took the sleeping bag as the design driver since it is the the most important gear piece for me.  I care that it not get too compressed.  I want it to stay as lofty as possible, really, but it needs to be protected.  Therefore it needs the protective stuff sack and the current design is the one I should start with.  I wrapped the tape measure around the current one and figured out the tightest circumference I would want to hold.  I used that to find the diameter of 7".  So that is where I am going to start with the width of the pack.  I also always put the sleeping bag in the bottom of the pack so I just need a curved bottom of the pack.  A nice fit will be nice because the Six Moon was a little too big and I always had to stuff clothes in there to get  a well compacted back pack.  It was frustrating because I never had a well figured out plan with how to stuff things in there all the time and I know that it was awkwardly crushing the sleeping bag or etc...  This will be a nicely welcomed change.  It's simple, it requires zero thought to put together, and I can use the clothes to wrap around all the awkwardly shaped items like the cook pot, the food.  (That reminds me that I need to make a new stuff sack for food.  Something lightweight that fits inside the pack well.)  Is it really only the cook pot?  Heh, beers at some point for sure.  Oh, and the water bag or bottles, maybe the poncho if I use it.  That lends me to believe that I can get away with a much smaller pack.  The only things that take up any real space are the sleeping bag, the down jacket, food, and the cook pot/fuel.  Actually, at some point it will be the bear can but I need to come up with other ideas for that later. I do like the idea of the bear can on the outside of the pack.  That lends me to believe I can make the pack the right size for everything and figure out a way to strap it on.  I can tackle that issue later, though.

Strap Testing

I know that I am going to be trying a lot of different strap ideas or configuration.  Instead of sewing the straps into the seems of the pack, I need to sew in another sheet of fabric that extends out an inch or two from the seem down the side of the pack.  This will allow me to easily get different configurations of the straps without having to actually take apart the side seems.  I'll only need to remove the straps themselves.

That works for the sides down near the base of the pack but where the straps connect to the top of the pack, I am going to just sew them into the back of the pack.  They are easy enough to get at to take apart anyways.

Sewing

No internet for almost a week but finally it was fixed today.  Someone literally drove down the street and caught the cable wire and tore it out of the house.  The funny part is that the AT&T people that came that day when the street was blocked off, didn't even fix it.  They cut the wire and left it like that.  What morons.  The guy that came out today was cool but obviously was pissed at the laziness of others.

I put the sewing machine together today and figured out how to use it.  I tried a few different stitches in hope of finding something that works well.  I had to play around with the tension of the threads(obviously a common activity).  I guess I could say that I have a pretty good idea how this thing works.  Now I need to get some basic dimensions put together and find some fabric to use and get a basic test model built.  I think that using old sheets or equivalent will mimic the type of fabric that I want to use for my initial design, so I think this could be a good place to start to see what happens.  Well that's not true.  I think pillow case material which is a little thicker is probably the better option.  I feel like sheets might be too thin to hold any serious weight.  Than again, I'm not trying to carry any serious weight.  I'm trying to build a semi-working prototype that I can learn how to sew on and get some basic idea what I am doing.  This will ensure a working model essentially that I can build a more functional prototype off of.  It's a learning curve and I need to slow(or quickly)  build all of my skills to get towards the major goal of a functional CDT pack.

Pack Testing

Yesterday, I filled up the Six Moon pack that I had with basically everything that I take with me on a long distance hike.  Except for the food; I didn't really have any of that lying around.  Instead I filled up a gallon jug with water.  Since Harley was coming with me, I figured that I could get rid of some of it somewhere through the couple of hours we would be gone.  I tried out a configuration of my new strap idea.  It wasn't the best test model because the geometry and the straps themselves were a little uncomfortable but the concept was certainly proven.  I had some issues with the straps being too tight around my neck.  It wasn't bothersome enough to prevent me from hiking for over an hour like that but in the future I am going to need a wider platform.  That will allow the straps to really hug onto the middle trapezius muscles.  Geometry will correct the right fit so that there is no digging into the shoulders, as commonly seen on current packs when carrying loads for extended periods of time. 

The pack weight itself, though, felt good.  It was really weird at first.  I could tell that something was off.  My side to side movements felt weird and when I bent over (especially to the side) the pack was strangely centered.  The pack weight didn't shift at all on my body.  It was more upright and didn't rotate with me.  There was no moment of inertia there needed to move the pack with my body.  When I got back up, it was easier.  There was less strain on my muscles to do so.  I guess a good way to picture it is when you bend over with your pack on, there are times when you feel that pack is going to keep going and pull you down with it.  I didn't get this sensation nearly as much.  I know that I have worn packs for over 3000 miles now but this was different and once I got used to it, I wasn't a huge fan of going back.

I put the pack on the way it was intended after this test phase and it just didn't feel right.  Something was out of place.  The weight felt alright on my shoulders but not good enough.  I was expecting to put it back on the right way and fall back in love with it but I didn't.  I wanted to take the pack back off and put the configuration back to what I was testing.  That's a really good sign because I think a few geometry changes can shore things up for me and ensure that the pack will fit me properly.

I also came up with idea to figure out how to design the ideal pack for my body.  I think the best way is going to be tracing my body while it's up against a mirror.  I can have a roommate of mine draw the outline on the mirror while I stand right next to it.  It's an easy and simple way of "tracing" the profile of my back.  Then I can begin to figure out what shape I need to make it.  A good contoured fit like the Jam had is going to be more comfortable on the shoulder and hips.  The higher friction area on the back will help keep some of the load off those areas directly.  And a nice snug pack will ultimately be most comfortable.  The problem with that may be the wicking away of sweat off the body.  The right fabric will need to be chosen.  In the ultralight community there is no room to add the weight to add vents, plus the closer the load is to the back, the less it will pull the body backwards.  I want the center of gravity as far forward as possible.  Otherwise, the pack is just pulling you backwards as you need to pull it forwards, as you walk.

Design thoughts

I took my little pack and loaded it up with some weight to see how the straps felt.  It wasn't enough weight though.  Maybe 10 lbs.  I guess that's a significant amount when compared to my real pack weight but really not enough to thoroughly test it out.  Either way, the bag felt really comfortable.  The straps are the real problem, though, they loosed up too easily and that's mainly because they are these thin maybe 1/2" wide straps that don't have enough friction to prevent the slippage.  Tomorrow I am going to get my packs out and load them up with all my weight and test some things out.  I want to play around with the straps a bit and also get some basic dimensions for a size and fit.  Just a rough outline that I can start with so that I can start thinking about putting together a basic design.  Having the packs all loaded up will give me the information that I am looking for in regards to strap design.  The ideas I have here are the main focus I have for an improved design.  I actually feel kind of dumb for not realizing that I could have done this 2 days ago to figure out the initial feasibility and basic structure that I need to think about next.

It's good to be focused on working on this each day.  The blog has really helped keep my attention locked in.  I feel that I have to write about something every other day or so.  Therefore I need to constantly be productive even if it's brainstorming while I am busy or working all day on a 3-D model.

Better Straps

I came up with a really sweet idea to make better straps on the new pack yesterday.  It was really a simple concept but I think that it will work.  It has the principle that I believe is going to significantly increase the comfort of carrying a pack.  It has it's design flaws that need some thoughtful engineering but this idea I have could be a complete different kind of pack than the market has seen.  I am excited to prototype it and see where the potential lies in this design and use it to further create a better product for myself.  I wish I had a test model tomorrow so I can could see the principle in action.  I want to understand how it all might work and where the next step in the creative process unfolds. Either way, I have an idea to continue basing my custom design on.

Next up is learning to use the sewing machine with skill and building a prototype.  I guess my initial thought is to get the sewing machine out and learning how to do some different sewing patterns and then segueing into finding a sewing pattern that works for today.  Definitely not the end result but something that can really be applied to what I am trying to built in this prototype.  It's not a endurance bag equipped for a thru-hike; it is there to see the feasibility and learn about the dimension, fit, strap placement, comfort, initial design to get some packets incorporated to.  Preliminary type stuff to keep the ball rolling.  I just need a prototype that is strong enough to get me through these tests.  My sewing techniques and design will improve with the more time I spend doing it.  It need not be perfect right now.  I also need to start roughing out some rough sketches and dimensions.  A 3-D model would be sweet but initially I need to start with some sketches and take some basic dimensions from my other packs.  That will give me a starting point for my design and will allow my creative juices to keep flowing as I understand the form and function of each of those "other" packs.  A lot of work is to be done and that doesn't even include the free body diagrams I have been working on that I would like to have completed at some point.  Sweet, I'm loving this project.

Free Body Diagrams

Today I have been working on the free body diagrams for the pack.  I am trying to understand what the forces are on the pack.and where they are applied.  I don't like the idea that what is out there currently is the best design.  Understanding what the forces are on the straps, and how effective the hip belt needs to be are the key to streamlining the design.  Less is more in this approach.  I am looking for a stable design that is going to fit the scaled down approach a thru-hiker needs with my point of view.  A simple, lightweight, quick access pack that will fit the load that I will be carrying in it.  I also have the ability here to fit pack design around the use of my bear canister which will certainly see heavy use in Montana.  It is all those little inconveniences that slow you down or annoy you on a daily basis that slow your day down.  The less time spent on daily life necessities is more time spent taking in the beautiful scenery.  It has to be fast.  The closure of the Six moon pack is slow and annoying.  I had to roll it up every time and then clip it together.  It was slow.  And annoying every time I wanted to get something quickly out of my pack that I had forgotten about.  Like that granola bar, a headlamp, or the occasional drink mix.

The free body diagrams are definitely good work.  They are giving some real good insight into what is going on with the pack.  One thing I wasn't really thinking about was how the straps wrap around the shoulder and create a moment on that shoulder due to friction.  I was only really thinking about the tension in the straps themselves and not that huge frictional force that plays a major role in pack design.  It's really good to be working on a project like this.  I like the problem solving that I have going on.  I like the school work theory that I am back to understanding.

Sea to Summit Backpack

The easter bunny brought me the best gift I have gotten since the Jet Boil for Christmas.  It is this small backpack made by Sea to Summit and it is incredible.  It is this thin, flexible cordura fabric but feels strong.  The shoulder straps are so thin yet the pack feels incredibly comfortable.  It is exactly the type of thing that I have had in mind.  It packs down into a little stuff sack about the overall size of a racquetball.  I love this little thing.  It is so lightweight and a perfect size for taking around town or as a nice day rucksack. 

This pack also gave me some great ideas for a backpack.  Ideas that are not on the market now.  I was blown away by this pack and I saw things in the way it was durable and simple at the same time.  I started to question a larger scale version because it is sort of how I have viewed my next back pack.  That's when I began to take a closer look at the functionality of the hip belt and shoulder straps.  They have typically been designed the way  you see them on most backpacks but why?  Where does their purpose really lie?  The hip belt as well.  These are many questions that need to be answered.  That thought process is the jump start I have been trying to achieve and now it is time to put my new ideas to good use.

Fueling the hike.

I started putting together the meal plan for the CDT and understanding what type of calories I should be ingesting.  During the hike, your body is a machine.  It is a power plant.  You ingest food and your body turns it into 30+ miles of rigorous hiking every day.  It's not a long walk on the beach with a young love interest.  It's a fast pace grind where you are pushing your body at all moving times of the day.  I need the right fuel for the fire.  The right amount of protein will keep my muscles strong and replenished.  Too much and I'm taxing my body's system.  Carbs are my fuel.  They supply my body with all the energy it needs.  It is the main source of fuel.  Fats are the vessel for receiving necessary vitamins.  Good fuel storage that my body will be burning constant stores of.  A good diet is necessary.  I need to find more information on high performance sports nutrition.  Everything I have found so far has no clue to how much protein my body really needs.

Continental Divide Trail 2012

I decided to hike the Continental Divide Trail in 2012 with Spartan and Flannel.  It's definitely going to be a "solid in your mouth."

First Post

Yeah, I finally started a blog about my adventures.