Layout Department

Creep

In printing, creep is the movement of your page contents in a zine because of paper thickness and folding. Specifically, the content on the innermost pages of your zine is going to look like it’s shifted away from the binding (compared to the content of the outermost pages) — unless you adjust for the creep. Creep only happens for binding methods that involve folding - so if you are perfect binding your booklet, you don’t have to worry about creep.

If you are making an informal zine (or if your zine is short) you absolutely don’t have to worry about creep. Also if you have wide open margins around your content creep is less of an issue. You don’t even have to trim it off! But if your booklet or zine is longer, the pages sticking out the front edge can look a little sloppy, and you might want to use a guillotine cutter or stack cutter to square them up. But in that case, sometimes you can end up trimming off the content on the edges of the inner pages — adjusting for creep moves the printed content on the page around to account for this before you print. This makes your content line up across pages and results in a more polished look.

How to adjust for creep in Layout Department

  1. Choose your paper type from the dropdown. We’ve provided two “approximate” papers for a best guess for common thin paper stocks, if you want to get the best accuracy or use other types of paper, use the custom entry.
    • Copy (75gsm / 20lb)
    • Text (90gsm / 60 lb)
    • Custom: enter a value in millimeters for the “creep increment” – how far to move the content on each page. The section below has instructions for how to calculate this.
  2. Choose which way to shift the content of the pages. You can:
    • Towards spine: shift the inside pages (nearest the centerfold) toward the spine of the book.
    • Away from spine: shift the outside pages away from the spine. You would want to choose this option if you are using a full spread image on the centerfold, since the other options could create a white line in the center of the page where there is no content.
    • Both: moves the innermost content (closest to the center of the book/signature) towards the spine, and the outermost (closest to the first and last pages of the book/signature) moves away from the spine. This reduces the largest shift by half.

Creep is useful for Booklet format (not Covers, Perfect Binding, or Magic Zine). Creep is off by default, but if you choose a creep amount, the “Both” shift direction is the default; you can change that in Settings to your preference.

How to measure a custom creep amount

In the Layout Department creep section, choose the “Custom” option in paper type dropdown. Then it’s going to ask you for a “Creep increment” in millimeters. So what’s a creep increment? It’s the amount of distance between the same vertical line on consecutive spreads.

There are three ways to measure this: the easy way, the more accurate way, and the no tools way.

You’ll need:

The easy way

  1. Measure the total thickness of your zine in millimeters. If your zine has a different type of cover paper (and you are laying it out separately) - then don’t include the cover in the thickness measurement. Calipers are the ideal tool for this job if you have them.
  2. Do some quick math: creep_increment = total_thickness / (number_of_pages / 4 - 1)
    • You can avoid doing this math by plugging in your total zine width measurement into the handy spreadsheet template and finding your answer labeled “spread creep increment, calculated from width”.
    • For reference, with this method we found that the creep increment for 20lb copy paper was about 0.23mm and for 60lb/89gsm text paper the increment was about 0.34mm.

Ok - so what’s up with this math? Remember, we’re trying to estimate how far apart content will shift from one spread to the next. And the (number_of_pages / 4 - 1) bit gives you the number of spreads. There are two pages to a spread and we’re printing on both sides of the paper - so that’s the 4. And we subtract one spread because there is zero creep on the centerfold. So we assume that the thickness of the zine gets distributed evenly across each spread. We also assume each portion of the thickness translates one-to-one into creep shift across the page. This last assumption isn’t entirely true (because folds add some extra shift), but it’s generally not too far off. If you really want to dig in - check out the next section.

The more accurate way

  1. With your zine folded, make a pencil mark on the bottom edge of the pages about 20mm away from the spine. Squeeze the pages together when you do this and try to keep your line perpendicular.
    • You can see the creep if you spread out your zine with the centerfold down flat and the outer cover facing up. Your pencil line will now look slightly diagonal.
  2. Starting with the first spread before the centerfold, measure the distance from the fold to your pencil mark and write it down.
    • If you are using calipers, we placed one prong inside the centerfold pulled tight to the paper. Then we aligned the other prong with the center of the pencil mark.
    • If you are using a 24 page zine, for this first measurement you’ll be aligning to the pencil mark on page 10.
  3. Keep moving toward the front of the zine, repeating the measurement for each spread until you finish with the outermost page (the front cover).
    • If you’re short on time, making 5 measurements should do the trick. Making a few more will increase the accuracy of your final creep increment by reducing the error contributed by any single measurement.
  4. Calculate the average difference between spreads. This is the creep increment.
    • Here’s a handy spreadsheet template to help you do this. Make a copy of the spreadsheet (File -> Make a copy) and fill in your measurements in the table. The answer is labeled “spread creep increment, measured” and is in bold. The creep increment you’re looking for is the slope of the trend line on the data.
    • We found that measuring the distance on the centerfold was usually fairly different from the other measurements - likely because our caliper technique was different from the rest. This changes the results slightly, so we don’t use a centerfold measurement for the slope calculation to make things more accurate.
  5. Bonus points: compare the creep increment you get from this method to the one from the simple method.
    • This method usually produces a slightly greater creep increment than the simple method - usually about 1.2x. If your result is drastically different (less than 1x or more than 1.5x), this might be a hint something is off.

The no tools way

This method is the least accurate, but also doesn’t require any special tools. It won’t produce perfect results, but it can be used in a pinch.

  1. Look up the paper caliper for the paper you are using.
  2. Do some quick math by plugging in your caliper into the handy spreadsheet template and finding your answer labeled “spread creep increment, calculated from caliper”.
    • The gist of this math is you take the paper caliper, use it to estimate the total zine width (in mm), and then follow the same calculation as method #1.
  3. Increase this number by multiplying by somewhere between 1.3 and 2.0. Since we didn’t measure anything, we need to account for the extra creep from the fold. Generally, we think you need less adjustment for thinner paper (say 1.3 for 20lb copy paper) and more adjustment for thicker paper (say 1.7 for 60lb paper).

References