Cheap Comfortable Waterproof Carry-on Size Backpack

Hi, everyone,

this is my first Instructable and I want to share this backpack I recently made :)

I'm not professional and still have to learn a lot.

It took me around 2-3 months to complete but worked once a week. I think it could be completed in few weekends.

Total cost was ~30£

Step 1: Materials

Waterproof fabric ( ~ 2 x 1.5meters)
Fabric for lining ( ~ 1.8 x 1.5meters)
Fabric for padding ( ~1.5 x 1.5m)
Big zipper (0.85m)
Smaller zipper(0.48m)
Light flexible plastic for the back (0.05 x 0.3m) x 2 pieces (I used some kind of plastic that I found laying around)
Bias tape ( ~3 m)

Keep in mind that if you change the design or size you will require more/less of the fabric.

Also:

Scissors
Sewing machine
Fabric glue (optional)

Step 2: Design

Before I started sewing this backpack and sketched a bit (I'm not that good at it tho) and came up with few specifications.

Waterproof
Minimalist design
Have a pockets for pens
Have a pocket for 15.6 inc laptop
Could be opened almost fully
Comfortable
Have a back support

Step 3: Cutting&sewing

This part the trickiest and takes the most patience but practice makes it perfect. I started by cutting all the pieces than sewing padding to it. To the back I sew to pieces of plastic because I wanted to be hard before that covering with padding. After this comes time to add lining and then sewing all the pieces together. I did this in this order :

Sewing :

all the pieces individually
front pocket with the zipper to front piece
straps and to the back piece
side pockets to side pieces
zipper to side piece
side piece to back ( I recommend doing this first instead of front because it's harder to reach back)
back with front

I found sewing bias tape to raw edges inside of the backpack too complicated so instead I decided to use fabric glue to do the trick :)