On the second-to-last day of my last trip to Rome, I was tired, lost, and wandered upon an art supply store on a narrow street near Piazza Navona.
While there I discovered a product I’d not seen in the US before- masking liquid in a pen- and eagerly bought it for about 7€. I immediately began using it in my travel journal for my paintings of things I saw in Rome and found, after a little testing, that I loved the effects it created.
When I got home to Seattle, I was shocked to see the same pen selling in local stores for more than double what I paid in Rome, and, while the price was much lower online, the reviews there at the time were pretty terrible.
After reading a few, I realized that most of the reviewers sounded like they were using the pen very differently than I was- and getting much less satisfying results- so I decided to write this quick tutorial for success using the Molotow Grafx Masking Fluid Pen.
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Paper: Do’s and Don’t
This pen was developed for use on watercolor paper, so you’ll have mixed results when using it on other types of paper. In testing, the BEST results were achieved on very close-fibered, smooth paper- paper that either had NO texture or paper with a stamped texture, like watercolor paper. The worst was on open-fiber paper like sketch pads. Thickness/weight of paper seems to have no effect on the final result.
DO: use on smooth or stamped paper
DON’T: use on open-fiber paper, like sketch pads
Masking Pen Prep: Do’s and Don’ts
This is a pump marker, which works very differently from a typical marker. The liquid inside will not flow unless manually pumped into the soft nib. To prep your marker, place the tip on a scratch piece of paper and press down until the nib moves back into the barrel and release. Repeat, gently, until the blue fluid flows well into the nib.
DO: pump the nib into the barrel gentle EVERY time you start to use the pen.
DON’T: use the pen without pumping or when the nib isn’t generously flowing.
TIPS for Using the Molotow Masking Fluid Pen
Because the nib won’t automatically refill, you’ll need to stop periodically and pump the pen. The fluid should be flowing onto the page, rather than the nib feeling as though it is dryly dragging across the page. If the pen isn’t leaving fully opaque, almost-pooling blue marks behind, you need to pump more and reapply.
DO: pump the nib until the pen leaves fully opaque marks.
DON’T: move forward to painting if the mark is translucent or shows the white of the underlying paper- paint WILL bleed.
Painting Over and Removing Molotow Masking Fluid
Let the masking fluid dry fully before painting. I give it about two minutes for details or double that for large areas.
Once dry you can paint over the blue masking fluid. When you have finished watercoloring and the paper is 100% dry, you can remove the masking fluid.
Typically, I rub with my finger to remove the fluid, but you can also use an eraser.
DO: Apply masking fluid thickly, in order to allow easy removal by rubbing.
DON’T: rub aggressively, as aggressive abrasion to your paper may damage to the surrounding color.
Final Thoughts on Using Molotow masking fluid pens
This is my two cents on this somewhat controversial new product: This pen has a learning curve that will disappoint less careful users, but is an outstanding product. I think most of the negative reviews are probably not using the pen correctly. The pen is meant for certain papers, and requires a unique step- pumping. Master those obstacles and lay down a thick layer of masking fluid and give it the appropriate drying time and I think you’ll love this pen as much as I do!
I first learned about watercolor masking fluid in my high school art class. As a budding artist in high school, I reveled in the creative space of my high school’s art department. Often, I even snuck into the art classrooms when I should have been in other classes to check in on a bit of pottery that had just come out of the kiln or to finish up a portion of a painting. I remember the first time I was introduced to masking fluid- it blew my mind!
As a messy watercolor painter, I loved making huge pools of color and blending them together with clear water. Because of the messiness of my style, clean lines were almost impossible to maintain, but masking fluid was a game-changer.
Back then, and especially on a high school art department budget, masking fluid was a precious commodity, and was difficult to use. The tiny bottles of masking fluid- which would have to be applied with a small paintbrush that would inevitably be ruined by the vicious goo- cost over $10 each (and we regarded them so preciously, that often they dried out before they could be used!)
Unless a student artist was working on a final project or a watercolor painting to be entered into a competition, in those days we generally swapped out masking liquid for rubber cement. Like making fluid, rubber cement created a waterproof barrier between the paper and watercolor pigment. However, rubber cement was difficult to apply precisely and even more difficult to remove.
Often, when using rubber cement as masking fluid, the removal after the watercolor paid had dried would result in torn paper and disappointment. What we wouldn’t have given in those days for liquid masking in a pen like these Molotow masking fluid pens which can be applied precisely and removed (usually!) without drama.