I have noticed that when I’m writing scratch notes on the back side of waste printer paper with my fountain pen I get blobby lines. It usually feels difficult to write clearly, especially when I scribe crossing paths in a (pointless) attempt to clarify my handwriting mistakes. Of course there are many variables at play in writing, but I was curious about why it seems particularly crummy in the common case of scratch paper.

This post looks at realized line widths for the same pen, the same ink, on three kinds of paper. My working mental model is that a wide line makes writing more blurred and blobby, and therefore harder to read.

Results

Properly designed notebook paper is smooth and less toothy. Line widths on notebook paper are 10% narrower and have very consistent width. It is probably also sized with treatments that limit the absorption of the ink. The archival paper seems also to be sized causing the ink to stand proud of the paper; on the other hand it is about as rough as the copy paper causing a wider line with feathering.

The standard deviations are based on three measurements each, so are not brilliantly reliable. However, the significant smoothness and narrowness of the notebook sample are consistent with eyeball observation.

Measurement Conditions

Ink is Pilot Iroshizuku in the Yama-budo color, a beautiful magenta-purple ink. This ink is very liquid, even runny, compared to an ink like Rohrer & Klingner Schreibtinte document ink. The latter is waterproof, but is acidic and corrosive to pens in addition to smelling bad.

I tested on three kinds of paper:

1. Copy paper is generic a generic printer or laser copier paper.
2. Archival paper is Southworth Business 25% cotton 20 lb. (75 grams/square meter) and is listed as acid and lignin free.
3. Notebook paper is from an Oxford Black n’ Red notebook. The lines are qualitatively similar to those from an Oxford Signature Journal.

The pen is a cheap knock-off of a TWSBI with an EF nib. The nib came with the pen, but is not made by the cheap-o producer. I believe it is a rhodium-plated steel.

Data and Results

I drew a set of lines on samples of the paper. Notice, in the following figure, that the journal paper smeared–this did not corrupt my results but it illustrates a common problem I have with this writing.

Zooming in to the practical limits of my scanner shows the same three samples in a different order. Notice how uniform the journal paper’s line is (at right), and how feathered the archive and copy paper are (center).

To get a more accurate measurement I put the samples under the microscope with a calibration slide on top to get the absolute scale. All photos use the same oblique bright-field lighting. The line looks shiny on the copy and archive paper, though much more so on the archive paper. The line on the notebook sample is very consistent and flat.

I measured each line’s width at three arbitrary places transverse to the line. These three measurements are summarized in the first table. With only three measurements the numerical utility of the standard deviation is questionable; however, simple inspection shows that the notebook has a more consistent line width with smaller feather features. That is followed by the archive paper line, with the copy paper bringing up the rear with bad feathering.