External frame backpack

I went backpacking with a borrowed pack last month. The trip was great and the pack was great, but it felt wrong to be in the wilderness relying on equipment I wasn't familiar with. I didn't know how the straps worked together or what gear went on the outside. And I need a lot of time to work things out, so I didn't really get the hang of it during the three days I had the pack.

I decided to build a pack. If I were going to do this really properly I would buy a pack and take it apart and put it together to get a handle on the construction, but on accident I thought about how good upholstery tweed would look in a 1940s rucksack silhouette and it was settled. The only thing is, I am the littlest bit stubborn so if this pack isn't comfortable I will still take it to the ends of the earth because I am so attached to it.

The frame is some crutches. I was excited to find them because I don't know where to get aluminum pipes. So far they are a little difficult to work with. The molded plastic is attached really permanently. And I thought I might preserve the height adjustable portion, but  I accidentally broke one of the tubes while I was flexing it. 

I wanted wool tweed but at the fabric store the synthetic tweed upholstery felt fuzzy, like it would pick up dirt amazingly on the trail. So I got something crisp. It was lucky I picked a geometric pattern because it made cutting straight lines easy- I don't have a good work surface for projects this large.