The following instructable details how to build your own gym/duffel bag. The pattern is simple, and easy to make. I chose to create my gym bag because I had an old sail that I wanted to re-use the canvas from, and I was in need of a new gym bag for school.

This is my second time creating a duffel bag from this pattern, and I haven't had a problem with it to date. The bags produced are able to take a beating, and still draw a lot of attention for their looks. So what's their overall best feature? They cost about 5 bucks to make!

Step 1: Materials

Since I create my duffel bags based on my needs, I use a random measurements in my pattern. In other words, I eyeball it. The measurements in this 'ible are based on my preference, and you can modify them to produce a duffel bag of whatever size you need.

Materials:

-An Old Sail, or some form of sturdy material. I would highly recommend using canvas for this project, as it is a sturdy and durable material.

-A Carpenter's Square, or some form of measuring tape. A square will pay off when you need to trace out rectangular shapes!

-A Circular Object, I used a mixing bowl, this will be used to create the patterns for the two circular ends of your bag!

-A Zipper, its length is dependent on how long you want your bag to be.

-D-Rings if you are planning on making a bag with a shoulder strap

-Optional: Material for the handles I just used sailcloth

Step 2: Cutting Out the Pattern

Cut out four circles from the canvas first. These will serve as the ends of your bag, and will be sewed together in pairs of two to make the bag more rigid.

Next, we get to do some math! Fold one of the circles in half, and measure the length of the straight edge that you created by doing so. Then, multiply this measurement by 3.14. This will give you the length of the rectangles that make up the main part of the bag. In my case, I cut out circles with 9" diameters, so I ended up with a length of approximately 28.25 inches. It's better to slightly underestimate this measurement than to overestimate it.

After you perform your calculations, cut out two rectangles of canvas that are of the measured length. The width of these rectangles is up to you, their width will make up the width of the bag itself. I cut mine to be approximately 28.25" by 16".

I also cut out three additional pieces of cloth to use for making handles and sewing stoppers on my zipper.

Note: leave room for seams in all of your cutouts

Step 3: Sew the Main Body

Take the two sets of fabric circles and sew them together. Sew the two fabric rectangles together as well. You should be left with two circles of cloth and a rectangle, each being two layers thick. Pin the cloth before you sew it. On a side note, I personally used tape. I find that canvas is difficult to pin, and the pin holes stay visible later on.

Next, take the two shorter sides of the rectangle of cloth and fold them over by about 1/2". The side that you fold onto will be the inside of the bag. Pin these folds in place, and then sew along them.

Step 4: Handles and Zipper

Next, affix the zipper to the cloth rectangle, with the zipper material pinned to the folds that you have made on either of its ends. Cut the ends of the zipper so that there's about 1" hanging off either end, and unzip it to separate the two sides. Then, sew the zipper onto the bag.

After the zipper comes the handles. I created my own by folding two pieces of canvas and sewing them into long, rectangular shapes. The size and width of the handles is up to you, along with their placement on the bag. The ends of each handle should be placed evenly from either side of the cloth rectangle. Make sure to leave an ample amount of room between them as well. In my case, I attached each handles' ends approximately 3" apart, and 5.5" from the sides of the bag. Fix a handle on, and secure its ends with stitching; repeating the process for the other side.

If you're going to attach D-rings to the bag for the shoulder strap, now's the time to do so. Sew a small rectangle of cloth that's slightly smaller in width than the diameter of the D ring. Fold it in half with the D-ring secured in the fold, and sew the D-ring into the piece of cloth. Then, secure and sew the D-ring onto one of your circular canvas cutouts. It is important to note that the position of the D-ring should be away from the edge of the circle, leaving room for the seam. It should also be sewed onto the side of the circle that you want to be the outside of the bag. Repeat this process for the other D-ring.

Step 5: Putting It All Together

You're almost done! At this point your should put the zipper back onto its tracks, creating a cylinder of canvas that is zippered shut. Turn this piece of cloth inside out, so that the handles are inside of it. You can now sew stoppers on the excess zipper if you choose to. I did so using two small canvas rectangles folded in half.

Now, take one of your canvas circles, and either baste or pin it in place onto one of the ends of the cylinder. Attach it with the side that you want on the outside of your bag facing inwards! I would highly recommend basting it in place over pinning it, as you'll end up with fewer if not any folds in the ends of your bag this way. Then, using your sewing machine, sew each of the ends of the bag onto its main cylindrical body. If you have attached D-rings to your canvas circles, make sure to affix the circles to the bag so that the D-rings are lined up with your zipper.

Step 6: Finished!

Turn your bag right-way out and admire it, you're done!

Comments are welcome, and be sure to attach pictures if you make your own bag!

Also, if you're interested in creating your own projects like this, along with electronics, be sure to check out my blog at www.coffeeandcircuits.blogspot.com.

Thanks!