First I figured out the size I needed for the bottom of my coffee filter by using the a coffee filter - I accidentally used the last one I had so I had to get one from a friend :-).
If anyone is interested I can make a PDF of the pattern so you don't have to go through the trouble of figuring out the sizing. :-)
Here is the template I made on thick paper.
I can take a photo when I make another one and post it. This part was pretty frustrating and tough but I basically just pinned the upper part around the circle and sewed it together. I used lots of pins and pricked myself a lot. I don't know if you can tell in the following photos but I had made the upper part a little longer than necessary so there would be a small overlap of the edges. I decided I'd rather have an overlap and room for error than cut it too short and have to start over. :-)
Here is the final piece inside out (I trimmed the edges at the bottom after taking this photo).
While making this I came up with an idea for a pattern that might be easier to sew - I'll post about that when I get a chance to work on it.
I plan on making a few more of these so that I can have one to use when one is in the wash - I make a lot of coffee and don't want to risk not having a clean filter. :-)
Since the fabric had been pre-washed I tested it out and it made a perfect pot of coffee. If you make one just make sure to take it out, rinse it and let it dry when the coffee is done so it doesn't sit wet in your coffee machine.
Supplies: Sewing machine, old coffee filter (for measurement), thick paper (for the pattern), pencil, fabric marker, compass, thread, canvas fabric.
Cost: $0 (I already had all of the supplies)