Hi Ray, it sounds like you've got the slicing covered, but just to make sure yes like Pilou write above you can use boolean difference to slice a solid with a 2D curve including a set of lines and the booleans are oriented around keeping things solid so the lines will leave the "side walls" where they cut, resulting in solid sliced results unlike Trim.

For a thread script, see the "Nuts and bolts" script from Max's page here: http://moi.maxsm.net/media/files/

Also some other scripts are collected here: http://kyticka.webzdarma.cz/3d/moi/ and instructions for installing a script are in the FAQ here: http://moi3d.com/wiki/FAQ#Q:_How_do_I_install_a_plug-in_script.3F

- Michael