Pocket Folder Printing: Some Paper Considerations

It helps to learn to think like a printer or, more specifically, to think like a printing press.

I had been working with a print brokering client to conceptualize a custom pocket folder with a brochure saddle stitched into its center fold. I had been thinking of sheet sizes appropriate for the digital printing I had suggested for the interior pages, but I really had not given much thought to the pocket folder paper stock, other than to tell my client I thought she should consider 110#, 120# or 130# cover stock weight.

Taking Press Requirements into Account

To begin, since my client wants a 12” x 9” pocket folder (oblong) instead of a 9” x 12” pocket folder (upright), and since she wants a 6” vertical pocket on the back cover of the pocket folder, I stopped and did some math.

The flat size for such an offset printed product would be 30” wide (12” + 12” + 6” pocket) plus bleeds, plus gripper margin (the part of the printing press that pulls the press sheet through the equipment) and any printer’s marks, color bars, etc.

I know that press widths go all the way up to 50”+ (or probably more). I also know that press sheets come in various sizes. However, now it was time to get more specific.

Since I already had received five bids on the job, I needed to look closely at each printer’s press equipment. It so happened that the lowest bidder had an offset press that could accept a maximum 30” press sheet. The second lowest bid was from a printer with a 40” press. In this case the pocket folder flat size would not be a problem, but the first printer could not handle a 30” unfolded pocket folder on their maximum sized press sheet.

At this point—fortunately–my client is considering an 8” wide front cover and 12” wide back cover for the pocket folder. (The job is morphing as she considers design options and pricing for the custom pocket folders.) This option would fit on the first printer’s 30” press (8” + 12” + a 6” pocket = 26”).

But What About the Paper?

Having the proper press doesn’t necessarily mean having the proper paper. The weight of cover stock (I had suggested 110#, 120#, or 130# cover stock) is the weight of 500 sheets (one ream) of paper at the basic cover size of 20” x 26”.

(Text stock has a different “basic size,” which is 25” x 38”. This is actually why you can measure sheets of 100# cover stock and 100# text stock with a caliper, and the cover stock will be much thicker than the text stock. It is because the basis weight of the cover stock and text stock are determined using different press sheet sizes.)

That said, a 20” x 26” sheet would not be large enough for the flat, unconverted custom pocket folder my client wants (even with the short fold on the front cover). You’d still need room for bleeds, gripper margin, printer’s marks, color bars, etc. What to do?

Fortunately, even though paper is weighed at the basic size (“basis weight” at the “basic size”), you can still buy paper that is of different dimensions. For instance, if you’re a printer, you can buy 25” x 38” text stock, or you can buy 28” x 40” text stock, depending on the size of your press.

But what sizes of cover stock can you buy? I wanted to check and make absolutely sure. Furthermore, cover stock comes “coated one side” (C1S) or “coated two sides” (C2S). More specifically, you would be more likely to find a cover stock measured in “points” (thousandths of an inch) that would only be coated on one side (such as 12pt C1S). For paper that is coated on two sides, you would be more likely to select a 120# white gloss cover stock, for instance (which would normally come coated two sides).

So how is this relevant? If my client wants to print on both the inside and outside of her custom pocket folder, she will need a C2S sheet (the printing would look different on the two sides of a C1S sheet). Now in many cases, you wouldn’t print on the inside of a pocket folder. You’d leave it white. After all, the pockets are on the same side of the press sheet as the front and back covers until you convert the job (fold up and glue the pockets).

More Paper Choices to Consider

So I had to find out my client’s plans. Did she want to print 4-color on one side or two sides?

To be safe I went to two websites:

1. 1. First I went to a paper comparison website that listed paper weights side by side for bond, cover, text, ledger, etc. (all weighed at different basic sizes). The website even included point sizes, allowing you to compare one sheet to another (on an approximate basis, since paper thickness still varies from one paper brand to another). So, for instance, you can see that 120# cover stock is roughly the same as 15pt. C1S paper. This will be very useful information depending on whether my client will need to print on one or two sides of the custom pocket folder press sheet.

1. With this information in hand, I wanted to make sure the proper press sheet sizes existed. So I went to the International Paper website. (I looked for Carolina Coated cover since I know it is a good C1S sheet.) Fortunately it comes in 23” x 39” and 25” x 38” (for the first printer’s 30” press, he can just cut down the sheet, but for the second printer’s 40” press he can use the sheet as is). So paper size and press size need not be deal breakers, depending on which of the two printers my client prefers. For the C2S option, for now I picked a paper at random: Kallima cover. The website noted custom pocket folders as a good use for the paper. Fortunately, it also noted availability in 24” x 36” sheets. Again, although this is too large for the first printer’s 30” press, he can cut the sheet down to size. It’s always better to cut down a large sheet than to not have a large enough sheet in the first place.

What You Can Learn from this Case Study

1. 1. Think in terms of the flat size of a commercial printing product. How large must the press sheet be, and how many copies of a job can you fit on a sheet?

1. 1. Also think about the size of your printer’s press and the maximum sheet size it will accommodate. Your printer probably has an equipment list with this information on his website.

1. Check paper websites to make sure the proper sized press sheet exists, and then leave it to your printer to buy as much paper stock as he needs for your job.

This entry was posted on Monday, September 21st, 2015 at 4:33 pm and is filed under Pocket Folder Printing. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.