JP, when reading your problem I'm trying to understand if the printer is behaving as designed or if HP has a problem. This excerpt is from the "using your printer" doc.
Select margins options
By default, the printer leaves a 5 mm margin between the edges of your image and the edges of the
paper (17 mm at the foot of a sheet of paper). However, you can change this behavior in several ways.
● In the Windows driver dialog: select the Paper/Quality tab and then the Layout button.
● In the Mac OS Print dialog: select the Paper Type/Quality panel and then Layout.
You will then see at least some of the following options.
NOTE Under Mac OS, the available margins options depend on the paper size selected in the Page Setup dialog. For instance, for borderless printing you must select a paper size name that includes the words “no margins”.
● Standard. Your image will be printed on a page of the size you have selected, with a narrow margin between the edges of the image and the edges of the paper. The image should be small enough to fit between the margins.
● Oversize. Your image will be printed on a page slightly larger than the size you have selected. If you cut off the margins, you will be left with a page of the size you selected, with no margins remaining between your image and the edges of the paper.
● Clip Contents By Margins. Your image will be printed on a page of the size you have selected, with a narrow margin between the edges of the image and the edges of the paper. In this case, if the image is the same size as the page, the printer assumes that the extreme edges of the image are either white or unimportant, and do not need to be printed. This may be useful when your image already contains a border.
● Borderless. Your image will be printed on a page of the size you have selected, with no margins. The image is slightly enlarged to ensure that no margin is left between the edges of the image and the edges of the paper. If you select Automatically by Printer, this enlargement is done automatically. If you select Manually in Application, you must select a custom page size slightly larger than the page on which you intend to print. See also Print with no margins on page 49.
Print with no margins
Printing with no margins (to the edges of the paper) is known as borderless printing. This can be done only on rolls of glossy paper.
In order to be sure of leaving no margins, the printer prints slightly past the edges of the paper. Any ink deposited outside the paper is absorbed by the sponge situated in the platen.
NOTE If you wish to print with no margins, you must ensure that your image will fill the page. If your image is smaller than the page, it will not be automatically stretched.
You can request printing with no margins in the following ways:
● In the Windows driver dialog: select the Paper/Quality tab and press the Layout button. Then select Borderless.
● In the Mac OS Page Setup dialog: select a paper size name that includes the words “no margins”. Then, in the Print dialog, select Paper Type/Quality > Layout > borderless.
When you select Borderless, you must also select one of the following Image Enlargement options:
● Automatically by Printer means that the printer automatically enlarges your image slightly (normally by a few millimeters in each direction) in order to print over the edges of the paper.
● Manually in Application means that you must enlarge the image yourself in your application, and select a custom paper size that is slightly larger than the actual paper size.
NOTE If the first print job after loading paper is a borderless job, the printer may trim the leading edge of the paper before printing.
At the end of a borderless print, the printer normally cuts the print slightly inside the image area to ensure that the print is borderless. It then cuts the paper again so that no residual part of the image is included in the next print. However, if the job is cancelled, or if there is white space at the bottom of the image, only a single cut is made.
