November 22, 2022

Production and Design Notes: Addax 31 and Addax 26

Mike, Ben, Jose, and Cindy (and Daikon) discuss the Addax 31 during a PPB meeting

What follows are production and design notes pulled from various meetings, our project management app, and our recollections. In some instances, we added to the notes to make them more descriptive of what we, in person, were discussing: folks asked us to share more about design choices and considerations or explain more about aspects of the manufacturing process. We first experimented with this format for the Old School Carry-All; see our Production & Design notes: OSCA edition. Now, it’s the Addax’s turn.

We share these notes in the hopes they give you a sense of what it’s like to be here on the factory floor and understand more about what goes into realizing the design of a bag like the Addax. 

  • ADDAX 26 and ADDAX 31 NOTES -

  • When our design team came together to discuss the next addition to the TOM BIHN line, our designer, Jose, pitched up this idea: create a roll-top bag, something that we didn’t yet have in our backpack collection, designed with commuting in mind. His vision included implementing the following features into this new bag:

    We went through many different prototypes of what would eventually become the Addax 31. 

    An early design of the Addax by JoseAn early design of what would eventually become the Addax 31.


    Below is Jose’s feedback from the very first iteration of the Addax 31:

    The Good:



    The Not-so-Good:

    Roll-top panel

    Exterior side pockets

    Interior mesh pocket at back panel

    Laptop Pocket

    Changes for the next sample:

     Exterior side pockets

    Roll Top Panels

    Back panel


    There was one main challenge that we were trying to solve: how do we achieve a clean look for the maximum number of rolls while also allowing the bag to buckle together with any number of rolls?  The day after our meeting, Jose proposed sewing the male buckle ends to the webbing at the back panel that holds the shoulder straps. This helps bring the folded roll top panel towards the back panel and leaves a clean-looking roll even when the bag is not completely filled. He also suggested swapping out the male and female buckles on one side, allowing the bag to buckle filled to max capacity, without an extra piece. Could our roll-top problems finally be solved?


    The question of pocket height also came up, as the bag needed to be able to roll all the way down, which would limit the height of the water bottle that could fit. Mike suggested that many of these issues could be addressed with an exterior water bottle pocket – a first for us here at TOM BIHN!


    When Jose brought this sample to our next meeting, we felt ecstatic about this sample. Finally, it seemed like our roll-top issue had been solved! We loved the versatility his solution provided, now you could roll the bag one, two, three times, or not at all! There were a lot of other things we loved about this version too. The exterior water bottle pocket was balanced with the Cambiata-style pocket and was able to fit in both without too much issue. 


    Cindy tests out an Addax 26 sample in the showroom
    Cindy tests out an Addax 26 in the showroom.


    Below is Cindy’s feedback on the Addax, after traveling with the first X-Pac prototype:

    What I really like:

    What I'm a little unsure about:

    With the feedback in mind, Jose then began to implement many changes to the next sample, most notably dividing the laptop pocket and adding an interior zipper. However, in an early prototype we felt a "bump" when unzipping the exterior laptop compartment, we realized this was caused by the interaction between the interior and exterior zippers.


    Below are excerpts from notes detailing the Addax construction process with co-Production managers Fong, Honguyen, and Trang:

    We suggested using bartacks to hold certain parts down and away from the zipper track to help the zipper glide better. 

    The back panel is difficult to sew.  There are a lot of different parts going into one area, making it very complicated. The zipper used is a bit softer and more flexible, better for the laptop. When it comes to sewing, it makes it very difficult to incorporate not only softer fabric with harder fabric at the bottom, but also compounding fabrics, zippers, binding, foam, mesh, and corners. Many layers, complicated and difficult!

    Honguyen suggested cutting the back foam slightly smaller.  This provided a bit more generous spacing for the joining of the bag and helped with binding bulk, at the final interior and exterior back pieces. 

    One touch that Jose wanted to add to the Addax’s exterior laptop compartment was a zipper garage. It gives the zipper an extra level of protection from the elements, especially important for the laptop compartment, and we liked the look. It’s a small piece but required some design iterations, what feedback did you provide to Jose? 

    Trang was the one who came up with a better way to construct the zipper garage in this particular back panel piece. She suggested changing Jose’s original two-piece panel into a one-piece panel with a longer extension. It accomplished Jose’s goal while creating a more efficient production process. The new piece has a special fold internally where binding is not required and the zipper ends are protected at the same time. Also, the best part is that it looks good, especially as an exterior piece, with small details.

    Co-Production managers Fong, Honguyen, and Trang's interview excerpts continued:

    Sewing a new bag with a new fabric also led to some exciting, new challenges for production. Here are some of their thoughts on working with X-Pac:


    Fong explained that the X-Pac fabric has unique characteristics, different from Ballistic Nylon and all other fabrics we currently use. The feel of X-Pac seems to have a bit more crispness to it, it’s easier to crease during production and has very little give and flexibility. Working with it at the beginning was a little different and took a little bit of getting used to since it is not a very forgiving fabric. It may take someone with good sewing skills and attention to detail to work with this fabric. If a sewing mistake is made, there is a good chance that the panel cannot be reused on the same bag due to the punctured marks on the existing panel, which will need to be recut and replaced with a new panel piece. 

    Honguyen agrees with Fong and explained that with the X-Pac fabric there is no give (think sewing thick paper). When sewing this fabric one has to consider and prepare it for joining. This involves sewing a smaller inseam (normally 1/2 inch, now closer to 1/3 of an inch) to accommodate the fabric. At the later stages of joining the fabric, it makes it easier and provides just enough spacing.  It is an exterior fabric, so we have to be very careful with how it is sewn, basically no room for errors. 



    Below is also an excerpt of feedback from advisors Tom and Nik: 

    We translated the concerns about the corners and bottom shape of the bag to Fong, Honguyen, and Trang. 

    Fong: I think because I am so used to it, it is not as hard for me to sew the corners. I know where all the points on contacts are, and I know exactly where the hard parts are so I can make adjustments as I am sewing to accommodate these points of difficulty. It will take a bit of practice to understand the bag and how to properly sew it. 

    Trang and Honguyen both agree that once you understand how the fabric works, and how to manipulate it in a way that works best, then the sewing is not too different from our other bags. Of course, it will be hard at first, that’s why we always plan extra time for Production Managers to train the rest of the floor on sewing new bags.


    The idea to create a second Addax in a smaller size came from our Production managers, who are all on the more petite side. They loved the look of the bag but felt the 31 was too large for smaller frames. Jose tried a couple of different dimensions for the smaller Addax and had a few more petite members of the team try the bag to make sure that proportionally it felt right. We wanted the bag to sit close against the back and prevent it from pulling away from the back when fully loaded. 

    For the smaller Addax, we wanted to have all the same great features we loved about the larger Addax, especially the ability to fit a 16″ Macbook Pro even with the reduced dimensions. 


    Jose’s notes for creating the new Addax 26 sample:

    New Dimensions

    13W x 17H x 6D

    The change from our current Addax is in the height. I am making the height of the front and back panel shorter by 3” and shrinking the width by 1”. The new dimension would get us closer to a 21/22 liter bag.

    Front Panel

     Back Panel

    Side Exterior Pockets


    During this fine-tuning process, we moved the wings of the backpack straps over to the inside panel, a deviation from the Synik construction. Since the Addax has a longer opening to the laptop compartment than the Synik, this change was added to ease the user’s experience of removing their laptop from the compartment by ensuring that the wings would not get in the way as one unzips the pocket. 

    When we received the next sample of the smaller Addax, we found that it could hold a 16″ MBP with some restrictions, this being that the laptop could only go in through the top side in one slide. Satisfied with these results, we had finally come to the finish line of the design phase. 

    Now, on to color choices. For the X-Pac fabric, we wanted something that would pop with the new fabric which led to the usage of Solaris Halcyon. We also wanted to try two new colorway options – Burnt Orange Ballistic/Moab Halcyon and Constellation Blue Ballistic/Island Halcyon. These choices were made by Maia, our Social Media Coordinator, and Jose, our designer, respectively. 

    Jose liked these two fabrics together due to their similarities. We liked the look of a monochromatic bag and thought that it could be a cool option! Maia was inspired by the fall leaves for her colorway. She loved the combination of colors, and so do we!


    Richard M - January 10, 2023

    Is there any chance that the Addax is ever made with Halycon exterior? I just like the flexibility of that material the best
    TOM BIHN replied:
    Hi Richard! At this time, we’d say it’s more unlikely that the Addax will be made with a Halcyon exterior. Mostly this is due to the factory that makes 400D exterior Halcyon was shut down in early 2022, so we are using the last of the rolls we have on hand currently, and it’s possible that we would not have that fabric available before the next batch of Addax are made. We do have our newer X-Pac material in the Addax, which has a bit more heft than Halcyon, but is more flexible compared to the Ballistic option.

    G42 - December 6, 2022

    Lots of notes shared for this one, very interesting to read! It’s cool to see how the whole team brings perspective on function and manufacturing challenges (and that Daikon is leaning into his supervisory role).
    Thanks for keeping both side pockets in the final iteration – they’re very useful.
    And that’s an intriguing shade of sage’ish green X-Pac Cindy is demo’ing…
    TOM BIHN replied:
    Thanks Wendy! That sage’ish green is my new favorite :)

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