This post is a little different than my usual “info about a kind of leather” but I thought I’d share a brief post about a bag I’m developing. The prototyping process and what goes into the design process.

I’ve been making “box” corner totes for a few years now and last year we came up with a 3-piece design that we really liked that allows for interesting types of combos with the leather.

The inspiration:

After a fellow crafter suggested that the design could be adapted into a back pack, I started to think about other ways to make the “theme” into other bags. I’ve been dying to make a messenger bag for years but we’ve never really had the time to work up a design. Additionally this design had the possibility of being something new and different.

Working out the changes to the pattern:

The first step was adapting the pattern. Tote bags look great if they get wide at the top but a messenger bag needs to keep a more or less rectangular profile. This meant that the middle piece needed to be a trapezoid, that narrowed to roughly the same width as my bottom seam. My first attempt came out too narrow and honestly looked more like a backpack:

The flap also came out wildly too long and in the above picture I’ve actually cut it back and shaped it.

Strap attachment issues:

The next pattern came out much better, but when I went to attach a strap I noticed a problem: The flap, which originally had a much more rectangular shape didn’t allow for the handle/ring attachment I had planned.

Instead of starting fresh, I cut the already sewn strap to allow for the strap attachment:

Now we had the general design of the bag:

Another test of the pattern:

Next step was to draw the pattern out for the strap and then test it again. To save a little sewing and gluing time I drew the pattern out a one piece:

I found a thinner leather and we sewed the design and added straps:

The leather was a little thinner than ideal but the strap attachment worked.

3-piece Prototype:

Now to try it as 3 pieces and add a couple pockets while we’re at it:

We also decided to try adding a top handle:

Final Prototype (for now):

Complete with front and back pockets and a strap that’s absurdly too long for any normal human (but I didn’t want it too short).

What’s next?

After carrying this prototype around at a convention this weekend I got lots of compliments but was also able to see some things I’ll change before this ever hits production. The top handle is slightly too far forward and a little big. The back pocket is about 1″ to narrow to fit an Ipad with a case, both easy fixes.

I’m also thinking about change the flap shape to more echo the shield on the front and reduce the “lobes.” I think the pattern in the top right of the picture below may be the way I go.

So this is still a work in progress, but I thought I’d share the process and some of the lessons learned. I’d also love any input you’d like to give on this design.