Preflight - PDF fixups - how to Scale pages to US Letter, NOT A4!

Here' the best explanation I could find:

• ISO Tips to Save You Time

  Simplified Enlargement and Reduction

  Many copy machines have preset magnification factors for enlarging or reducing a copied document in order to print it on a different paper size. These presets typically take the form of buttons labelled A3→A4 and so forth. This eliminates wasted margins and saves you the trouble of trying to guess the right magnification factor, which can lead to a heap of misspent paper. Below is a table of the magnification factors between the most common A sizes in case the copiers at your local library do not have such presets.

The bullet above is taken from this useful article with historical fact about why A4 and the International standards:

https://www.swiftpublisher.com/useful-articles/paper-sizes-and-formats-explained

Yes I think I understood your inquiry correctly.

I was referring to when you click on print to use the Adobe PDF  as the default printer option, not your actual printing hardware device.

When you select this option to print directly from Acrobat, you click on the "Page Setup..." and select the desired page size. 

All you have to do next is fit, shrink, or scale the oversized pages under "Page Sizing & Handling".

However,  this setting will not stick, meaning that is only executed on the fly at printing time.

If you have to have a permanent preset that you'll reuse many times later,  you may also click on the Properties button which will open up the "Adobe PDF Document Properties dialogue window".

You'll notice three tabs.

Two of the the three tabs allows you to select "Letter" page size (also on the fly and right before committing the print to PDF action), then by clicking on the "Advanced" button.

In the next dialogue window click the + sign "Paper/Output" --->>> and select "Letter" from the dropdown menu  labeled "Paper Size".

These tabs are:

• Layout
• Paper Quality

Since you're printing to PDF this will

produce an exact PDF from the original file with the new page size.

Both of the tabs mentioned above are part of the Adobe PDF Converter Advanced Options.

The third tab is:

• Adobe PDF Settings

In this tab you can also produce a pdf from the source file, but you'll get much more options to customize and save those printing profiles for specific work, like embedding text and fontypes, working around image quality and image conversion methods,image colors, PDF optimization and tweaking some postscripting elements.

You can access those settings by choosing  the default preset from the dropdown menu "Default Settings:", and then clicking on the "Edit..." button.

In addition, look four lines below, where it says "Adobe PDF Page Size:".

In that dropdown menu you can select a desired page size or click on the "Add" button to customize and save your own preset.

When you're done you will be back to the "Print" dialogue window where you may reflow the page content using the  scale, shrink or fit options mentioned earlier.

Last, if you're on Microsoft Windows, you can also customize a specific page size preset from the control panel; click on Adobe PDF and a new ribbon menu bar will display under the search bar of that settings window.

From left to right,  you'll notice the following options:

"Add a device"

"Add a printer"

"See what's printing"

Just click on the "Print Server properties" link.

In the " Print Server properties" dialogue window that will open up, you can create and customize the desired page dimensions ticking the box "Create a new form".

Once you've saved the new form, it'll be always available as a " sticky setting" and it will always remain accessible from the lists that are are accessed at printing time with the method(s) described above.