blueman wrote:

Well, I am having 2 problems.
First, I am finding it hard to score precisely on a straight line
(even though I am following a steel straight edge). The blade keeps
wanting to slip away slightly.

1.) Use a utility knife blade with the tip broken off or use the blade
backwards, so the straight, non-beveled side of the blade is dragging on
the plastic. Scoring plastic is more like scraping than cutting.

2.) Slightly angle the blade so that it plows slightly into the straight
edge.


I've cut miles of styrene and plexiglasses by hand with this method
with excellent results. Try it!