Plotters aren’t as common as they once were. Today, many printers can get high enough resolution with dots that drawing things with a pen isn’t as necessary as it once was. But certainly you’ve at least seen or heard of machines that would draw graphics using a pen. Most of them were conceptually like a 3D printer with a pen instead of a hotend and no real Z-axis. But as [biosrhythm] reminds us, some plotters were suspiciously likeĀ typewriters fitted with pens.
Instead of type bars, type balls, or daisy wheels, machines like the Panasonic Penwriter used a pen to draw your text on the page, as you can see in the video below. Some models had direct computer control via a serial port, if you wanted to plot using software. At least one model included a white pen so you could cover up any mistakes.
If you didn’t have a computer, the machine had its own way to input data for graphs. How did that work? Read for yourself.
Panasonic wasn’t the only game in town, either. Silver Reed — a familiar name in old printers — had a similar model that could connect via a parallel port. Other familiar names are Smith Corona, Brother, Sharp, and Sears.
Since all the machines take the same pens, they probably have very similar insides. According to the post, Alps was the actual manufacturer of the internal plotting mechanism, at least.
The video doesn’t show it, but the machines would draw little letters just as well as graphics. Maybe better since you could change font sizes and shapes without switching a ball. They could even “type” vertically or at an angle, at least with external software.
Since plotters are, at heart, close to 3D printers, it is pretty easy to build one these days. If plotting from keystrokes is too mundane for you, try voice control.

Back in the late 70’s I ran a test fixture that was composed of a commodore PET, an HP SCR meter, and an HP printing plotter, the fixture was used to test L-network antenna tuners for radio ranging and surveying equipment.
The HP was a flatbed type, used a static charge to hold down the paper, and drew, and wrote on it with a pen…. it was much quieter than the Panasonic plotting printer….. and you had a choice of several different colors of ink to use.
Most current vinyl cutters also accept pens. I have 3 different brands and they include a way to hold a sharpie, gel pen, or fine-point. I can pretend to be president and auto-sign things!
A vinyl cutter is essentially a single pen plotter. Some vinyl cutter knife holders are based off of old plotter pen designs.
I have always wondered how good plotters are for text? I mean I would assume unlike printers they cannot make “dots” well since they require their pen tips being moved to actually draw so stationary things like dots etc cannot be done well?
Dots are done with small squares. It’s very readable, as long as the pen is good. Also, being inherently a vector based system, the text scales well.
Actually, even though ALPS make all of these mechanisms, they don’t all use the same pens. There are to my knowledge, two different sizes. the typewrites and printers use a larger pens and mechanism than the smaller computer printer-plotter and calculator plotter type mechanism.
My memories of pen plotters are mostly unpleasant. On small, dense multi-color plots the ink would soak and swell the paper so that the rotring metal tip pens ripped the paper when multiple passes went over the same spot. Using mylar instead of paper wore down the tips so fast that a thin line became a smudge before the job was done. More expensive ceramic tipped pens were available, but my recollection is that they still weren’t durable enough for large prints on mylar.
This was a grit-wheel plotter capable of plots at least 3 feet wide. Fun to watch it in action.
These ALPS type plotters use ballpoint pens (short ones) and don’t have the problem of the ink soaking the paper.