At this point in time, the Coolest Fanny Pack has not hit production.  I know, we are sad too, but that is okay!  We have open sourced the design and manufacturing steps below.  Now everyone can be cool with the Coolest Fanny!

Step 1: Sketch

All great ideas start on a scrap of paper.

Carbon Fiber Fanny Pack Sketch

Step 2: Model

In this day and age, a sketch is then transferred to a computer and turned into a CAD model.

Carbon Fiber Fanny Pack SolidWorks Model

Step 3: Shape

For a prototype, it is okay to hand shape a master plug.  If this were to go to production, this process would be replaced with a CNC router.

Hand Shaped Foam Plug

After the rough sanding, it is important to bring in the detailer who can finish the plug and ensure it is symmetric.  How provocative!

Final hand shaped foam plug

Step 4: Gelcoat

To save time, we are going to be using the male plug as our final mold, which means the interior will be perfectly glossy and the exterior will need additional work.  To finalize the plug, we spray it with a mix of gelcoat and hi-gloss additive (to force an air cure).

Gelcoated foam plug for a carbon fiber fanny pack

Step 5: Sand and Wax

After gel-coating, the plug needs to be sanded to a smooth surface finish and then waxed.  If this were to be the outside of the fanny pack we would also buff the surface to a high gloss finish.

Sand and Wax a gel coated foam mold

Step 6: Layup Prep

Using the plug, determine the shape of the carbon fiber that needs to be cut out.  Do this by wrapping a scrap of fabric around the plug and trimming it to fit like you would want the carbon to fit.  In the case of a fanny pack, the pattern happens to look like a big diaper!

Carbon Fiber layup prep  Peel Ply Release Cloth

Step 7: Wet Layup

Time to get wet! For a one-off part, a wet layup is the way to go.  It is quick and simple, but also very messy!

Carbon Fiber Wet Layup for a fanny pack  Carbon Fiber Wet Layup for a fanny pack

Step 8: Vacuum Bag

Once the plug has been wrapped in carbon fiber you need to pull a vacuum on it to consolidate the layers and let the resin cure.  In this case, a simple envelope bag with release cloth , perf-bag, and breather bleeder will be used.

Carbon Fiber Fanny Pack Vacuum Bag Layup  Carbon Fiber Fanny Pack Vacuum Bag Layup

Step 9: Surface Layer

When making a part off of a plug instead of a mold, the surface finish is never going to be great.  After pulling the part and sanding it flat, it can be nice to add one final surface layer just for appearance.  This will eliminate all wrinkles and surface flaws.

Carbon Fiber Surface Layer  Carbon Fiber Surface Layer Cosmetic Skin

Step 10: Trim and Sand

It’s time to get artsy!  With the part laid up we will now trim it to size, cut out all the speaker and button holes, and sand it to the appropriate finish.  This step is messy, but it’s worth it for the perfect fanny!

Trimmed Carbon Fiber Fanny PAck

Step 11: Clear Coat

With the part cut to shape it is time to make her look pretty again! Bring on the clear coat!  Add many layers to achieve a deep clear finish!

Carbon Fiber Clear Coat Spray

Step 12: Assemble the Electronics

With the shell complete it is time to bring the fanny to life!  We dismantled two stereos, spliced together the four Bluetooth speakers and installed them with custom backing plates. We cut the backing plates on our laser, but they can be as simple as a piece of wood with two holes cut in each of them.  The Bluetooth speaker we used is Available o purchase on Amazon.

Carbon Fiber Fanny Pack Electronics

Step 13: Sew the Cooler

Now that we have the internals assembled we can start fabricating the cooler.  Based on what we had on hand, we decided to use thermal insulation blanket and clear vinyl to make the cooler.  Probably the hardest part of the whole project was sewing the Zippers… They are really tricky!

Sewn Interior for a Carbon Fiber Fanny Pack Sewn Interior for a Carbon Fiber Fanny Pack Sewn Interior for a Carbon Fiber Fanny Pack

Step 14: Attach the Cooler

With the cooler sewn, double sided tape (3M LSE Tape) and super glue (3M SF100) can be used to attach the cooler to the carbon.

Attach the Interior to the Fanny Pack  Clamp the Interior to the Fanny Pack

Step 15: Add Sunglasses Pocket

Once the cooler is in place, it is time to start filling features in around it.  We sewed a micro suede pocket with stiffening for sunglasses and glued it in using the same adhesives. It’s the details that make the Coolest Fanny a big hit!

Clamp the Interior to the Fanny Pack  Sunglasses Pocket on a Carbon Fiber Fanny Pack

Step 16: Back Panel

Getting to the end! All that is left is the addition of the hip belt. In order to attach this firmly we sewed Velcro to a panel of super durable rubberized nylon.  From there, we actually riveted and glued the panel onto the carbon fiber shell.  Velcro +Rivets + Glue = Life Proof

Riveted Carbon Fiber Fanny Pack Construction Final Back Side of Fanny PAck

Step 17: Attach the Belt

We made some slots in the carbon fiber for us to slide webbing straps through.  This provided an attachment on the sides of the hip belt (purchased on clearance from REI).   The center of the hip belt already had Velcro so we stuck this portion to our fanny pack and clipped in the sides!

Final Carbon Fiber Fanny Pack Final Carbon Fiber Fanny Pack

Step 18: Bump Music and Party!

The Coolest Fanny is complete! With speakers loud enough to throw a party anywhere and enough beer storage to almost get one bro drunk, it truly is a Party in a Pouch!

And beyond that, it also happens to be awesome to take traveling, rock climbing, quading, scootering, and just about anywhere else!

Carbon Fiber Travel Fanny Pack  Carbon Fiber Climbing Fanny Pack

Carbon Fiber Quading Fanny Pack

Carbon Fiber Party Fanny Pack

Carbon Fiber Scooter Fanny Pack


Life is Carbon Based



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