Creating a custom paper is recommended for the following reasons:
Generic Esko EPL files are mandatory to use for any kind of media. They use however the Epson Proofing Paper White Semimatte media type. Creating a custom paper allows to fine tune the printing behavior (by means of a Print Head Alignment and Paper Feed Adjustment) towards the used media.
A paper feed is recommended by Epson. From the Epson help menu: "When you use Epson special media, the optimal print results can be acquired without any modification. However, the paper feeding may go out of alignment due to the individual differences of the printer. When you are using non-Epson special media, you need to adjust the paper feed adjustment value according to the media, as well."
This KB describes the process of creating a custom paper for the Epson SureColor P7000.
The process might be similar for other Epson series as well.
Procedure
Environmental Specifications
Operate the printer within the recommended temperature and humidity range, therefore it is recommended to place the printer in a room with air conditioning.
Do not place the printer in direct sunlight.
Don't place the printer next to a heat source or directly in the path of the exhaust of a ventilator / air conditioning.
Keep the printer turned on so that the ink can keep circulating. Perform a pre-storage maintenance if you plan to leave the printer turned off for more than a week.
Load the paper in the printer and select as Paper Type "Epson Proofing Paper White Semimatte".
Install the Windows driver for the Epson SureColor P7000.
Install the EPSON LFP Remote Panel 2 utility.
Start the tool.
Click the Custom Paper Setup button.
Select the correct printer and select an Unregistered Custom Name, e.g. "#4 Unregistered".
Select as Reference Media Type "Epson Proofing Paper White Semimatte" (the same media type is used by the generic Esko EPL files).
Ignore all other settings at this moment and click the "Save..." button.
Enter a name.
Click "Activate" to load the paper setup on the printer.
Verify the ink level and make sure that the ink level is not critically low.
Verify the ink expiration date. Note that it is not recommended to use expired inks. Check the ink cartridge itself for the expiration date.
Execute a Nozzle Check and perform a Head Cleaning (if needed) via the Proofer panel.
Do a Print Head Alignment via the Proofer panel
Choose Uni-D option (automatic way) when using uni-directional printing (generic Esko EPL files use uni-directional printing).
Choose Bi-D All Color (automatic way) when using bi-directional printing.
The importance of a Print Head Alignment
Aligning the print head is the most important thing you can do to ensure the best print quality (to avoid: banding, a grainy or blurry output, mis-registration or “ghosting).
Go back to Custom Paper Setup window.
Click the Thickness Pattern button to print the thickness pattern.
Confirm the best print that has no gap of the top and bottom lines in the pattern from #1 through #15. The pattern number (1 to 15) correspond to the actual paper thickness (0.1 to 1.5 mm).
Select #3 in this case.
Click the Details... button of the Paper Feed Adjustment Value option.
Click the Print button and evaluate the printout. If the paper feed correction value is too small, black banding (dark colors) appears. In this case, move the slider in the positive (+) direction. If the paper feed correction value is too large, white banding (white or faint colors) appears. In this case, move the slider in the negative (-) direction. Please consult help for more information about this process.