Art Masking Fluid

Using art masking fluid with watercolor

What is art masking fluid and how is it used? Masking fluid is liquid latex, which is a natural rubber, though there are synthetic versions of it as well. As a watercolor artist it allows you to protect parts of your painting. It allows you to quickly paint over areas of your paper without having to try and paint around complex shapes. Masking fluid is used by Acrylic artists as well watercolor artists.

For this demonstration I am using Winsor and Newton’s Art Masking Fluid which I have been using for about 14 years without any problems.

What you need to apply art masking fluid

Here is a list of the tools you will need when applying masking fluid to your watercolor paper.

Equipment for applying art masking fluid

Figure 1: Masking fluid, water container and range of old watercolor brushes

  • Bottle of masking fluid, also known by various brand names.
  • A water container filled with about3/4” of water – for use with cleaning the latex from your brush
  • Old watercolor brushes, do not use your good brushes as any latex left in the brush will destroy their good point very quickly. I have a number of such brushes with varying shapes, one has quite a fine point (obtained over time as hairs have worn away) for masking narrow lines and shapes.
Concentrated dish washing liquid for use with art masking fluid

Figure 2: Concentrated dish washing liquid for use with art masking fluid

  • Dishwashing liquid.
Crepe eraser for remove dry art masking fluid

Figure 3: Crepe eraser for remove dry art masking fluid

  • Crepe eraser for removing the dry masking.

Steps for apply masking fluid

The first step after you have completed the drawing for your painting is to give your bottle of masking fluid a good shake. I do this about 15 minutes before I need to use it to allow all the bubbles thus generated to settle back down. Otherwise you get masking fluid up the side of your brush when you dip it into a half full bottle.

While waiting for the bubbles to settle down add some dishwashing liquid to the container you will use for cleaning the masking from your brush. Stir it all up so the liquid soap is dispersed evenly throughout the water.

Add some dishwashing liquid to water used to remove wet art masking fluid

Figure 4: Add some dish washing liquid to the water container

Add a few drops of dishwashing liquid in water and stir used to clean art masking fluid

Figure 5: Stir up the dish washing liquid

Start by dipping your brush into the soapy water. Drag the brush over the rim of the water container to remove some excess water and then dip it into the latex masking.

After dipping brush in soapy water pick up some art masking fluid

Figure 6: After dipping your brush into the soapy water dip it into the masking fluid

Now you can paint the masking fluid onto your dry paper over the areas you need to protect.

Paint art masking fluid directly onto dry paper

Figure 7: Paint the masking fluid onto your dry paper over the areas you want to protect

Between every one or two times that you pick up fresh masking liquid rinse the brush out in the soapy water. If you fail to do this the masking will start to dry on your brush and you will end up throwing it out!

Dip brush in soapy water before dipping into art masking fluid

Figure 8: Frequently clean you brush in the soapy water

Continue this procedure till you have finished applying the masking fluid to your watercolor painting.

Finish placing all your art masking fluid and let dry thoroughly

Figure 9: Continue applying masking fluid to the watercolor painting till finished

Let the masking fluid dry completely. Once dry you can lay your watercolor wash over the unprotected areas of your painting. In my case I have used the masking to protect the flowers and branches of my painting so I can easily lay in the background watercolor wash. The masking will protect the paper underneath from staining. However sometimes you may find you have missed a spot leaving you with a small patch of watercolor where it isn’t wanted. This will need to be removed with some light scrubbing after the masking is taken away.

Once art masking fluid is dry lay down your watercolor wash

Figure 10: After the masking is totally dry you can lay your watercolor wash

After your watercolor wash has totally dry (this is very important) then you can proceed to the next step of removing the masking. The easiest way to do this is to use a crepe eraser. You do not have to press very hard as the latex of the masking fluid seems to be attracted to the rubber of the eraser and comes off quite easily.

After the watercolor wash is totally dry you can remove the dry art masking fluid with a crepe eraser

Figure 11: After the watercolor wash is totally dry you can remove the dry art masking fluid with a crepe eraser

You now have the background done and can concentrate on the details in the areas which were protected.

After removing art masking fluid from watercolor painting

Figure 12: The painting with the dry art masking fluid removed

If you had left a gap in your masking now is the time to remove as much of the unwanted watercolor paint as possible with a barely damp stiff brush. You can also use this same brush to fix any edges that you feel are not correct or too sharp before proceeding to the next step.

Key points for using masking fluid with watercolor paper

Make sure you only apply masking fluid to watercolor paper which is totally dry. Do not apply it to wet or damp paper or the masking fluid will be absorbed into the paper and will damage it when you remove it. Also, it should not be used on soft sized paper – I use Arches watercolor paper which has plenty of sizing. Otherwise it could be absorbed into the paper fibres. If this happens it cannot be removed without damaging your paper.

Do not use it on soft sized watercolor paper. This means watercolor paper with very little sizing on it. I mainly use Arches paper and have never had any trouble with it. The problem with soft sized paper is that the masking may be absorbed by the paper and not be able to be removed properly without damage.

Clean you brush in the soapy water very frequently.

Don’t use your best watercolor brushes for applying masking fluid or they will be damaged.

Wait until the masking is fully dry before painting over it.

Wait until you watercolor wash is totally dry before removing the dry masking with a crepe eraser.

You can apply masking fluid over a dry area of watercolor wash before laying another wash. However a little of the watercolor being protected is likely to be lifted and may need to be reestablished anyway with more watercolor.

I only use masking when I really have to as it slows down the whole painting process rather than letting me get right into the painting – but there are times when it just must be used.

Hopefully this information will allow you to use art masking fluid successfully with your future watercolor and acrylic paintings.