my old backpack broke so i decided to make a new one myself.

so here is how to make a perfect backpack for the spring / summer. although not terribly big it fits quite a lot (a 13inch laptop fits perfectly). it has an extra pocket in the top-cover and an inside pouch to put a magazine or something similar.

although the sewing itself is not overcomplicated it sure helps if you got some sewing experience. and even with experience it will take some hours to finish, but the result will be worth the work!
i try to explain everything as good as possible with lot of pictures, but if things still remain unclear, feel free to contact me.

also since english isn't my native language i might use some unsual words - please understand!

Step 1: What You Need

materials
- 0,5 m of sturdy cotton fabric for the exterior of the backpack, 1,40 m wide
- 0,5 m fabric for the lining (non stretch! and best if it's cotton, too), 1,40 m wide
- 3 meters of belt strap 3 cm wide
- 1 zipper, 18cm long
- sewing thread
- 8 eyelets, 1,5 cm in diameter
- some metal parts whose names elude me - look at the pictures, if you know what they're called feel free to tell - they have to be the same width as the belt strap (3 cm). you need two rectangular ones, two rectangular ones with a movable vertical part in the middle, one carabiner-type thing and one the carabiner can connect to (the triangular one). those parts could also be plastic - just see what's available to you.
- 1 drawstring at least 1,20 m long

i chose a plain blue fabric for the exterior, green for the strap, zipper and thread and a striped lining.

tools:
- ruler, tape measure
- sciccors
- pins
- eyelet-tool
- sewing machine

Step 2: Prepare and Cut the Fabrics & the Strap

here are all the parts you need. i named them a - h to make them easier recognisable later. i added scematics for all the parts.

for the lining you need:
a) one piece 84 cm wide and 38 cm high
b) one piece 24 cm wide and 28 cm high
c) one piece (the bottom) 18 cm long and 26 cm wide with rounded corners - see scematic
d) and e) the two pieces for the top cover - see scematic
and two little pieces 3 cm wide and 7 cm long

for the exterior you need:
f) one piece 64 cm wide and 43 cm high
g) one piece 20 cm high and 43 cm high
c*) one piece 18 cm long and 26 cm wide with rounded corners - see scematic
h) one piece for the top cover - see scematic

these measurements (except the two little pieces of fabric for the lining) are all without seam allowance - add 1 cm of seam allowance on all sides before cutting out the pieces. where no seam allowance is needed is indicated on the scematics.
the scale of all the scematics is half the original size, except part a is a quarter the original size.
from parts a and f only the half is shown, you have to mirror the scematic along the center front line. mark all the lines inside the parts (red on the scematics) on the fabric parts as well, as you will need them in the process.

from the belt strap you need:
2 pieces 90 cm long
1 piece 23 cm long
1 piece 24 cm long
1 piece 6 cm long
1 piece 12 cm long
2 pieces 18 cm long

Step 3: Making the Top Cover

for the top cover you'll going to need pieces d & e and the 2 little pieces from the lining fabric, piece h from the exterior fabric, the carabiner metal part, the zipper and the 6 cm long piece of the belt strap.

fold the two little pieces of lining fabric and fold them in half lengthwise (so they'll be 3 x 3,5 cm).
sew them to the ends of the zipper.
then fold in the seam allowance on parts d & e where the zipper goes, pin it to the zipper and sew.

pin the two folds on the side shut.

Step 4: Making the Top Cover Part 2

now take part h and close the two side darts.

stick the belt strap through the carabiner-recipient and pin the strap to the exterior part of the top cover where indicated on the scematic. one centimeter of the doubled belt strap has to lie over the seam allowance. it helps to mark with pins where it goes.
the carabiner-recipient has to be facing to the inside. (see pictures)

pin the lining part and the exterior part together right side to right side and sew together along the rounded line - don't sew the bottom part. (this is all a lot easier to understand when you look at the pictures)

turn over the top cover and sew once around close to the edge of the top cover. it helps if you pin the the fabrics together with pins first (see pictures)

the top cover is now finished.

Step 5: The Lining

for this part you will need pieces a, b & c.

close the back seam on part a.

for the inner pouch fold the upper edge of part b over 2 cm from the right side to the left. then fold over again 2 cm. sew.

fold the seam allowance on the sides of the pouch part (b) to the left side and pin the inside pouch to part a where indicated (left side of the pouch to right side of part a). sew both sides.

now pin & sew the bottom part c to part a.

the lining is now finished. the right side has to be on the inside.

Step 6: Preparing the Back Straps

you will need the 4 rectangular metal parts, the 2 90 cm pieces, and the 2 18 cm pieces of the belt strap.

you have to seal one of the edges of each of the 90 cm belt straps (if they are made of plastic - if they are made from cotton you don't have to do it.) to do this take a lighter and pass the flame close to the end of the strap so that the plastic fibers start to melt, press the melted fibers together - carefully, since they are a little hot. i hope you can see the difference in the picture. you only have to prepare one end of each of the long pieces like this.

start with the sealed end and put one of the long straps through one of the rectangular pieces with the movable middle part accorsing to the picture. then put one of the rectangular pieces after it. (see pictures)

form a loop with the rest of the strap and put the strap through the first metal part (with the moveable bar) again - see pictures for how it is done. pull the end through about 6 cm and then fold back to the rest of the strap that you just pulled through.

now sew the 2 layers together by sewing a 3 cm square with a diagonal cross over it. see scematic and pictures for how it is done.
it can be a little difficult to sew this part because there is not a lot of space. just take it slow!

now take one of the two short straps and pull it through the rectangular piece and fold it over so that it lies double. sew another square with a cross about 3 cm lower than the metal part. the first strap is now finished.

repeat with the second strap.

Step 7: The Back Part

for this part you'll need the finished top cover and part g from the exterior fabric. you also need the finished back straps and the 23 cm and the 24 cm long piece of belt strap.

NOTE: with all the taking pictures and such i kind of got distracted and forgot to sew the top cover to the back with all the rest of the things. and i just noticed after i already sewed the rest of the exterior to the back part. then i had to undo the seams and put the top cover in where it belonged. so in some of the pictures the top cover will not be in the picture (just imagine it is there like in the later oictures under all the straps) - i hope you're still able to understand what is going on! sorry!

the 23 cm cm long strap will be the handle. fold both ends of the strap together so that the strap is double but half as wide and secure with pins (see picture).

now you have to pin the back strap, the top cover and the handle strap to part g where indicated on the scematic.

start with the top cover. mark the line where you have to sew it to the back with pins. now pin it to the back part:
it has to lie on part g so that the lining side lies on the right side of part g, the open end towards the bottom.

now pin the back strap and the handle strap to the back on top of the top cover. all have to face towards the upper end of the back part. look at the pictures to see how the pins have to be placed.

no take the 24 cm long strap and pin it lenghtwise over all the other things - pictures and the scematic should tell you how.

sew once close the upper edge of the 24 cm long strap and then once close the lower edge. be careful when sewing this part because there are a lot of layers and if you go to fast the needle of the sewing machine is in danger of breaking.
sew 2 times more back and forth over the upper edge-seam because there will be a lot of strain on this part of the backpack and you want the seam to be extra sturdy.

now fold the two back straps towards the bottom and sew over them close to edge 3 times (see pictures).

Step 8: The Exterior

you'll need: parts f and c*, the finished back piece.

pin and then sew part f to the back piece on both sides.

reverse the whole thing so that the right side is outside. pin the lose ends of the two back straps on the bottom of part f where indicated on the scematic. the end has to lie 2 cm over the line where you later sew the bottom on.

reverse again and pin and sew the bottom (part c*) to the rest of the exterior. reverse a last time and proceed to next step.

Step 9: Putting the Lining and the Exterior Together

you need the finished lining part and the finished exterior part now.

before you sew both parts together mark the place on the exterior where the belt strap for the carabiner will be with pins from the right (outside) side with pins.

put the lining part into the exterior part, the back seam of the lining has to line up with the middle of the back piece. the exterior is 5 cm longer than the lining. fix the lining with pins as shown in the pictures. then fold the part of the exterior that is 5 cm longer 2,5 cm to the inside and then again 2,5 cm. sew.

now make sure the lining lies extactly how it should lie inside and then from the outside fix the lining and the exterior together close to where the carabiner will go with to extra pins - see picture.

Step 10: Attaching the Carabiner

now you need the carabiner metal part and the 12 cm long part of the belt strap and the now almost finished backpack.

pull the belt strap through the carabiner and form a loop. press the loop flat and fix with pins. make sure that the part of the loop where the 2 ends of the strap meet is closer to the end opposite to the carabiner. (see pictures)

pin the strap to the backpack (the part with the 2 ends facing the backpack) and sew a square with a cross on the lower part like you did before with the back strap.

now to the last step!

Step 11: Making the Eyelets

almost there! all that's left to do is to add the eyelets and the drawstring.

8 eyelets are needed, with a circumference of 84 cm that's one eyelet every 10,5 cm. the placement of the eyelets can be found on the scematic. but you can also just measure where the go: start by marking one 5,25 cm from the middle of the backpart and another one 5,25 cm in the other direction. from both of them you can go in 10,5 cm steps for the rest.

i marked where all of the eyelets go with pins before i started with installing them.

since i guess there will be a description on how to install eyelets that comes with your eyelet tool i won't go into detail about it:
install all 8 eyelets (if you don't have the possibility to make eyelets you could also put button holes with your sewing machine but they won't be as sturdy)

if your string i made from plastic, seal both ends with a lighter like in step 6. in the picture you see the difference between a seal and an unsealed end.
thread the drawstring through the eyelets starting on one of the two eyelets that are closest to the middle front. tie a double knot in each of the ends when finished threading.

that's it!

Step 12: Enjoy!

finally!
enjoy your new backpack and take it out to the beach, the city, the library....

i hope you liked the instructable.
if you have a question or something was not explained clearly enough, please contact me!