how should I cut a piece of foam?

the height is 4". the width and length are 24". I want to cut into an angle. I am not sure how to explain. I don’t want to cut straight. what should I do? thanks
the foam comes from a futon bed.
It looks like a match box now. I want it to look like a semi triangle.

Sharp, I mean really sharp, knife and slice it as though you were slicing a tomato. Watch the wrist.

This entry was posted in foam cutting. Bookmark the permalink.

3 Responses to how should I cut a piece of foam?

  1. sensible_man says:

    Foam rubber, or foam insulation? If it is rubber, draw the lines you want to cut. Place a piece of board along the line and put your weight on it. Then cut with a utility knife. You can move the board for each successive cut.
    References :

  2. Lam Sanders says:

    Sharp, I mean really sharp, knife and slice it as though you were slicing a tomato. Watch the wrist.
    References :

  3. Grandmabird says:

    use an electric knife. and then wash the knife and put it away.
    References :
    crafters do this all the time