I’ve found that GUI scripting the Print Dialog rarely, if ever, works for me. Today, I saw the solution:
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1) Go to http://www.codepoetry.net/projects/cups-pdf-for-mosx
CUPS-PDF is a backend module for CUPS (Mac OS X's printing system)
by Volker C. Behr that, rather than printing to a device, prints
straight to PDF files that appear in a folder on your desktop.
2) Download and install the package (requires an admin password)
3) Follow the simple instructions on the CodePoetry site
*)
property OP : missing value
tell application "Printer Setup Utility"
set OP to current printer
set current printer to printer "Virtual Printer"
end tell
-- later on after getting your pdf files by printing to the Virtual Printer
delay 3 -- you can watch to check that this works in the Printer List window
tell application "Printer Setup Utility" to set current printer to OP