I believe this behavior may most often be caused by incorrect settings. But I also believe it is a bug somewhere in the Mac/LR/Epson printing pipeline. And the worst type of bug to figure out....absolutely intermittent and relatively seldom occurring.
I had this combo for nearly 8 years with an Epson 3800. Zero problems for 5 years, then every couple months, I'd get only about a third of the width of an image to print. Might happen 2 or 3 prints in a row. Found suggestions on LULA never to use the print button in the lower part of the right hand panel of the Print Module. Instead, after setting margins, profile, etc, click on Printer, then make final settings in the Epson driver window and print from there. That worked. For about 3 months. Then it happened again several more times over the following 3 years. My 3800 died and I replaced it with a P800. Had it now for about a year. I think I've had the behavior 3 times in this past year.
Last week, I had a print order of 4 copies of 20 different images. I made all image adjustments first, then began a very mechanistic, printing marathon. About ⅔ of the way through the printing, the third of the four prints of one image did the partial strip print. I simply put in the next sheet of paper, went through the identical button clicking routine and it printed fine. And all of the remainder of the 80 prints were fine.
Fortunately it hasn't become very common or persistent once it shows up. I don't like it, but I just live with it.
Brad
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