Thank you for your post.
I am unable to replicate the issue with a HP LaserJet M3035. Both printouts are identical
From both machines, instead of printing to the printer, print to a PDF file. Then, compare both files to see if they are identical. If the files are identical, try printing the PDF files. Does this work?
Have you tried reinstalling the printer driver under Mac OS X 10.10?
Any other information you can provide may be helpful.
printing to PDF (via the print dialog and via save as PDF in Filemaker preview) generates output of the correct size, and it prints the correct size from the Yosemite computer. Printing a 3x5 rectangle drawn in illustrator prints a correct size rectangle. I haven't been able to reinstall the print drivers because those pages are down at HP right now, but I've found something else that appears related to the problem. I had the page size set to a half sheet of paper (5.5x8.5 inches). If I print to 8.5x11 inches on page set up (via filemaker), the cards print the correct size on my problem (yosemite os) computer). If I change the page size back to 5.5x8.5 (even creating a new profile for that instead of using the old one), then the size is off. So it seems to have something to do with using a custom page size, but again, only from the computer running os x 10.10; the computer running os x 10.9 is fine. Printing from Adobe illustrator onto 5.5x8.5 paper also scales the image (even though its not supposed to) -- its slightly larger than the FMP output, but still smaller than 3x5. So, it looks like a yosemite or HP driver on yosemite problem right now, not a FMP problem. I'll replace the driver when I can and see what happens. Thanks.