# Differencing/Splitting/Trimming a dense pattern into a plane -- best tactic?

I’m having trouble with the final step preparing a file for laser cutting for which I have a dense 2D pattern (6000+ closed curves) that I’m basically trying to invert, as if die cutting the pattern into a single plane. (The negative will be the engraving toolpath).

I’ve tried a few varying tactics between trimming/splitting/boolean differencing the pattern onto a plane but everything seems to lag so deeply or outright fail that I’m not quite sure what the best tactic is besides doing it row by row, which it seems to be able to handle. Splitting the plane using the closed curves as cutting objects seems to be the most reliable, as long as I’m deleting the vestigial planes before doing the next command.

Anyway, that might be a fine (slow) solution, but I feel like I might be missing a more direct route that I wasn’t able to glean by searching around.

curve boolean?

I looked at curve boolean and understood it only as a method of combining selected regions of overlapping, closed curves into one combined curve, not for differencing curves from a larger surface (and I believe I need to be working with a plane in order to actually be selecting the area itself as the negative). Unless if I misunderstood an aspect of that command which would work for my need of differencing.

To use CurveBoolean for this, make sure your plane is the construction plane. Call DupBorder to get the outline of the plane. Get rid of the plane. Call CurveBoolean, set Output to Surfaces. Select your curves and the plane border. You may now have to wait a while depending on the curves. Click in the area that you want to keep. There may be another delay. Press enter and after possibly another delay, you should have your answer.

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Ah, output to surfaces is the trick. Thanks for clarifying Chuck!