Front view of bag with Mustard Beetle patches (strap unbuckled)

Back view of bag with Urban Native Era patch (strap unbuckled)

I started volunteering as a nature/tour guide at Bird Alliance of Oregon and Hoyt Arboretum this year and needed a water-resistant messenger bag to hold my gear (hand lenses, pinecones, dead moles, etc). Luckily I had just enough dry oilskin leftover from previous bags to make a scrappy improv-patchwork Mia Messenger Bag. I modified the bag to have an adjustable nylon strap (better for rain!) and added patches galore for maximum delight. The banana slug on the strap is a crowd favorite 🍌

Pattern

Mia Messenger Bag by BF Patterns

Bag features: two external slip pockets on the front, one interior device pocket with velcro tab closure, one interior zip pocket; main opening has both a recessed zipper and magnetic snap closure
Easily holds a 24 oz Hydroflask, a tablet or book, laminated 8.5 x 11 tour visuals, snacks, and a jacket.

Messenger bag when worn. Note the prominent banana slug.

Fabric & Supplies

Merchant & Mills Dry Organic Cotton Oilskin (245 gsm / 7.2 oz) in black, oxblood, storm, and fern (purchased from Modern Domestic and Charlotte’s Webbing)
Robert Kaufman Big Sur Canvas in Unbleached
Pellon SF101 Shape Flex Fusible Interfacing
#4.5 nylon coil handbag zipper trimmed to size
9” YKK #3 nylon coil zipper for interior zip pocket
18mm brass magnetic snap (optional)
Velcro for device sleeve tab (optional)
1.5” wide herringbone nylon webbing
1.5” wide plastic flat side-release buckle and plastic d-ring
1” swivel snap and twill tape for key lanyard
Patches galore: snail, toad, banana slug, you are on native land, American Kestrel, California Quail, Red-breasted Nuthatch, American Goldfinch
Worm and banana slug zipper pulls
Woven label (Subject to the Unstoppable Ravages of Time: All Things Return to Dust!)

Modifications

I experimented with improv patchwork using scraps of dry oilskin to create the main body of the bag. I omitted interfacing for the exterior fabric since I was working with a waxed fabric and didn’t have sew-in interfacing; I used a heavier lining fabric to compensate a bit.
After cutting the fabric but before assembling the bag, I sewed a bunch of patches to the exterior and lining. I used a small stitch length (~2.0mm) and a clear presser foot for visibility, sewed slowly, and pivoted often.
I prefer a heavier lining fabric for more structure and durability, so I substituted canvas for the quilting cotton suggested in the pattern.

I substituted lightweight interfacing for the recommended medium interfacing for the device pocket since I was using a heavier weight fabric. If I made this again I might use the medium weight interfacing—it’s a little floppy as-is.
The Device Pocket Tab (pattern piece 14) in canvas was a bit too thick to comfortably sew through, so I used a piece of cotton webbing instead.

I added a key lanyard by tucking the end of a length of twill tape (you can also use double-fold bias tape that’s been edgestitched) into the seam around the top raw edges of the main bag and lining. I threaded the free end through a swivel snap, folded under the raw edge twice and edgestitched the fold down to secure.

In the future, I’d make this out of a strip of fabric instead because the twill tape is a bit too soft and pliable for my liking. I’d also make it shorter; I made it long so I could unlock my door without taking my keys off the hook, but the length means it often gets stuck under everything at the bottom of the bag.

Mustard Beetle toad patch

Mustard Beetle snail patch

Recessed zipper with Curlworks worm zipper pull

Adjustable Nylon Strap with Buckle

I wanted a lightweight, water-resistant adjustable strap with a buckle that would make the bag easy to remove while wearing a rain jacket and bulky layers. Here’s how I modified the strap:

I shortened the outside and inside straps (pattern pieces 6 and 7) so they extended a few inches above the body of the bag. I sewed the side seams as instructed (steps 34–36), but stopped about ~1—2” from the top edges.
I turned the straps RS out, then folded the remaining raw side edges towards the WS at an angle until the top edge of the straps was slightly wider than my nylon webbing. Then I turned the top raw edges towards the WS. I ensured that the angles were the same and the folded edges of the inner and outer straps aligned. I trimmed some of the excess folded fabric to reduce bulk.
Next, I sandwiched the free end of the nylon webbing in between the fabric straps so that it extended about 2” below the top edges of pieces 6 and 7, then edgestitched around the three folded edges to secure. I added a zigzag stitch along the top edge only to reinforce the strap. See photo below.
Since I am right handed, I usually wear cross-body bags so that they rest on my right hip. I prefer that the buckle and strap adjuster falls along my chest for easy access. I cut a shorter length of webbing (16”) and attached it to the side that will face forward when worn, and cut a longer length of webbing (32”) for the side that will face backwards.
I threaded the nylon webbing through the side-release buckle and tried the bag on to find my preferred strap length.

I attached the side of the buckle with the adjustable slider to the shorter length of nylon webbing towards the front of the bag. I fed the webbing up through the slider, then slid on a d-ring before feeding it back down through the slider (the d-ring helps quickly loosen/lengthen the strap when worn). I threaded the webbing from back to front so the excess webbing ended up on the RS for easy adjusting. I found my desired length, added an inch or two extra, then folded the raw edge of the webbing towards the WS 2–3 times and sewed 1–2 stitch lines to secure (make sure that the folded end of the webbing is thick enough that it can’t be pulled back through the slider). See photo below.
I attached the other end of the buckle to the nylon webbing attached to the back of the bag (the excess webbing should be towards the WS here). I found my desired length, folded the raw edge of the webbing towards the WS once to enclose the raw edge, then sewed 1–2 stitch lines close to the buckle to secure.

I finished the strap by sewing on a cute patch!

How to attach the the bag to the nylon webbing.

How to feed the front webbing through the buckle and d-ring.

Sewing Notes

Dry oilskin is a wonderful alternative to waxed canvas for folks with sensory sensitivities. I love the look and practicality of waxed canvas, but I really disliked the feeling of wax all over my hands, legs, and machine after making previous bags. The Merchant & Mills dry oilskin is easy and pleasant to work with.

FYI: the black colorway does collect lint and cat hair 🤷🏻‍♀️
The oxblood colorway is a gorgeous muted purple-brown that my camera struggled to accurately capture. The pictures on Merchant & Mills are a good representation of how the fabric looks in person.

It’s nice to have BOTH the recessed zipper closure when it’s raining AND the magnetic snap for easy access to tour items.

Notes for Next Time

Add a wide slip pocket on the back exterior of the bag.
Use thicker interfacing for the device sleeve.
Make the key lanyard out of thicker material and shorten the length.

Interior zipper pocket, key lanyard, Inside Voices Label, and Bird Collective patches.

Device sleeve (closed), key lanyard, and Bird Collective patches.

Device sleeve (opened).

Keep In Touch

Thanks very much for reading! If you’d like in-person support and instruction, please sign up for my classes at Modern Domestic or reach out to schedule a private lesson. If you have any questions, feedback, or corrections regarding this post, please don’t hesitate to contact me!

scrappy mia messenger bag