March 29, 2009

This week: What is this thing, and what do I do with it?




Comic Tools reader Stephen emailed me saying that his girlfriend has bought him a ruling pen (good girlfriend), and he was wondering what it was and what do you do with it.

A ruling pen is a very old-fashioned precision drafting tool. It it one of the tools that allowed illustrators and letterers to create the kind of super-precise drawings that people now use illustrator to create. Think stuff like the Sears and Robuck catalogue.

A ruling pen is basically a two-pronged fork of metal with a screw that allows you to bend the points closer together or farther apart.


To use the pen you dip it into ink about half an inch deep and then lift it out,

Which will leave you with a very sizable bead if ink in between the prongs. The ink is held between the prongs by surface tension, and as long as you don't sharply hit the ruling pen it will stay there. Being able to hold so much ink at once means you can draw an insane amount of lines before you need to dip the ruling pen again.

After you've dipped the ruling pen, you need to wipe the ink off the outsides of the pen's forks, or else it will crust on or smear where it's not wanted. I like using a folded up paper towel. You must be careful NOT to allow the ink inside the pen to touch the paper towel or it will suck up your entire load of ink.


Ruling pens aren't generally used as a freehand drawing tool- they excel at precise ruling of straight lines and curves. Whether you're using a ruler or a French curve or a triangle, you need something that has a beveled or elevated edge. If your ruler lies flat on the page then the ink will get sucked right under the ruler and spread. An elevated edge insures this won't happen. I have two elevated rulers, one with cork backing and one with foam rubber. I prefer the foam rubber because it has some traction and stays put even on an inclined drafting table.

If your tool isn't beveled or elevated, you can tape pennies onto the bottom to raise it up.

To use the pen with a ruler or French curve, simply adjust the pen to the line width you want and draw against the edge of the ruler.

Ruling pens will draw for a crazy amount of time with thin lines, but as you can see in the picture below (click to enlarge), the thicker you go the faster you use up ink. However, you can get around this problem (and draw a razor-straight line of any, literally ANY width) just by drawing two parallel straight thin lines and then filling in between them with a brush, or even digitally later.

Old drafting tool sets also come with ruling pen attachments for their compasses, allowing you to ink the circles you've drawn with a totally even, uniform line. (which again, can be literally ANY width at all, by making two small lines and filling between them)

As you can see below, my ruling pen attachment has an adjustable joint to keep the ruling pen straight up and down with the paper, ensuring both prongs are always touching the page.


Next week: Tiny metal ball

19 comments:

Sarah said...

Reminds me of my engineering drafting class almost a decade ago. Thanks for this post on a lesser-known tool.

What is that skinny stripe-y pencil type thing near the back of your pile of utensils?

Comic Tools said...

A porcupine quill pen.

B2-kun said...

I haven't dusted mine from storage in ages. Might give it a try for nostalgia's sake. They can now usually be found on clearance at Office and Art Supplies stores.

Sam said...

I have a smaller pen that came with my compass. I fill it by dipping something thin in the ink, then drop a bead of ink inside the pen.

Anton Emdin said...

Thanks. Is there a great advantage in using this over a technical pen?

I guess what I mean is - besides the variable width and using your own ink, is the quality of line any better than a good pen?

Greg H said...

Coincidentally enough, I was just showing the same pen to my studio assistant this afternoon. I have my dad's set from engineering school in the 1950s, complete with the compasses in a gorgeous metal case.

You can save the step of wiping the excess ink off the outside by applying it to the inside of the pen with an eye-dropper or loading up an old brush (at least a #3 or larger).

To answer your question Anton, they won't give you a much different line than a technical pen, they're just easier to clean, have the variability you mentioned, and being simpler they're more reliable.

They're also a bugger to learn and be prepared for a lot of tears and spilt ink. Try and draw a set of plans with these things and you'll understand why CAD was invented.

Hugo Sleestak said...

Great post. I'm really mad about these jurassic skills. I guess it's the artsy survivalist in me, but I don't trust the digital age enough to surrender the old fought-for ways of doing things. Photoshop and Illustrator are great, but you can't afford to be crippled if you don't have them around.

Comic Tools said...

Anton: What Greg said.

Hugo: Love the phrase "Jurassic skills."

Anton Emdin said...

Thanks for that info Greg.

And Hugo - yes, my sentiments exactly! I gave up on brush and ink for a year, but I'm back, baby... I'm back!

Rivkah said...

THAT'S what you meant by "ruling pen"! For some reason I was thinking something completely different . . .

I actually have one of these in an antique compass set that I own, and I'd always wondered what it was used for as well. I'll have to test it out because I've never thought that the lines regular technical pens give to be very straight. Except for rapidographs, but ugh . . . the cleaning . . .

Rivkah said...

Rather I should have said "smooth" instead of "straight". Multiliners give straight enough lines with a ruler obviously, but the edges are more ragged that a person should expect for panel borders and even more highly noticeable after scanning.

Comic Tools said...

Rivkah: Yeah, ruling pen lines are as smooth as they get. So straight and perfect you'll want to cry.

Raluca Z said...

Thank you for reminding me I have one of those too...
I was looking for something do mark the pannels border so that I can still do them clean in photoshop but have the guidelines after erasing. Felt tip pens kept dying after 20 pages or so - when you use a felt tip pen for ruling you'll ruin the tip a lot faster.

Per-Erik said...

What is the mark of your ruling pen/compass? Would like one with that adjustable leg!

Beyla said...

Just discovered your blog. Glad to see some love for the ruling pen. It's probably the best thing for laying down masking fluid I've ever found.

The Big Blue Frog said...

I love my old rule pens. In the early 90's, we were still being trained (as graphic designers) to use rule pens as well as rub-down tone and lettering. I still have a nice collection of rule pens that even includes a rule-compass pen for perfect (ha!) ink circles.

johnholdway said...

You can fill it with a brush so you don't have to wipe it. Also I sometimes use watercolor in it.

Emily said...

I hadn't thought of using watercolor in it- I will have to give that a try. Do the lines come out relatively dark?

Steff Chan said...

Thank you for this! My dad just gave me his old set with absolutely no explanation except for "I know you like drawing". I was so confused as to what those nibs were. This really clears things up.