If your are like me and grew up on boiled coffee or have traveled to places where they make coffee 10 times the normal strength, a few grounds in your cup doesn't bother you. The wife however doesn't like grounds in the bottom of her cup.
We use the paper filters in our coffee maker and sometimes they will fold over and allow the grounds to spill into the container then wind up in the pot.
My solution to this was to cut a ring out of a 2 liter soft drink bottle then use that to hold the sides of the filter in place.
And since it has been quite a while since I have posted one of my plastic drink bottle tools here is a new one for you. It is a clear bottle so it doesn't show up well in the photos