I made a small jig to hold my exacto knife when cutting dollar tree foam board.
It works great for cutting control surface hinges.
I made 2 of them, 1 for straight cutting & 1 for bevel cutting.
One is made from plastic (UHMW) & the other is made from wood.



Doesn't make any difference what you make them out of.
The one made from wood was cut on a combination cut off saw to get the 2 different angles.