I have a tedious document production task that would be greatly simplified if I could use the dual-tray feature of the printer (a Canon MF414dw in this case.) Basically, I have an MS Word document with separator pages for exhibits, Exhibit A, B, C, etc. I output this to a PDF, then insert the exhibits (already PDF files) to assemble the entire PDF document. Then I want to print this in one go, with the separator pages printed on color pages fed from the manual feed tray of the printer and the content pages fed from the main tray. There are many exhibits and many copies to be printed, hence the desire to automate the collation.
To solve this, I figured I could create a custom paper type of Color Letter at 8.5" x 11.25", i.e. just slightly different than Letter size. MS Word can then output the separator pages to this custom paper type, and the printer could auto-select the tray based on the slight difference in size.
I can create the final PDF file with interlaced page sizes, but can't get it to print correctly. Researching says that the Mac printing system is incapable of driving the printer to auto-select the paper source based on the page size. Neither Preview nor Adobe Acrobat seem to do this. Preview insists on scaling all the pages to one paper type. Acrobat has a checkbox option to auto-select based on PDF page size, but it doesn't work.
Is there a solution for this very simple use case or is it not possible for MacOS (Sierra/High Sierra in this case) to auto-select the paper source from a dual tray printer? Preview really needs to support this and from researching the issue it's something Apple has turned a blind eye to for years.