How to lime paint and care for your lime paint brushes

Lime paint brushes (plafone) are the essential tools for lime paint applications.

They may seem too big, but after the first time you use them you will never do without them again.

Here is a guide on how to use and care for your brushes:

PRIME YOUR BRUSH: Before you begin your lime paint project, submerge the entire brush in a pail of water, shake the brush until all the water has dripped out. This will help keep the lime paint from drying out towards the heel of the brush. Never whip the brisles against any hard objects as this will damage the bristles.

SATURATE YOUR SUBSTRATE:  (say that three times really really fast!)

It is crucial that the substrate of your painting project is kept humid for several reasons:

• It allows the lime paint to cure and carbonate slowly and not "burn" by drying too quicky. If the paint dries too quickly it will turn out weaker and is more likely to dust when rubbed against.

• Allows for more open time to complete the selected area without painting over dried edges. 

Painting over dried edges or "feathering" over dry areas will leave a noticeable and unsightly spot.

It is critical to soak the substrate TO SATURATION. Test a small area by spraying water on a spot and wait one minute or so, spray again, does it change in color? does the water just disappear? if it does it is not saturated. spray it again then wait a few minutes then spray it again until it is saturated, meaning that it will not draw water in anymore. 

For very porous and dry substrates it is advisable to soak the substrate with a hose as described above, a day in advance and spray again just before the paint application. 

MOIST BUT NOT WET: There should not be any visible water present on the surface when you 

begin painting. Spray or mist the entire area and wait a little while before you start painting.

MAKE LIME WATER: Spaying the substrate with "lime water" instead of tap water has many benefits. Lime water contains free lime in a solubile form. This lime rich water will penetrate deep into the substrate and deposit the free lime as it evaporates improving a weak or dusty substrate.

This also works well for reinvigorate soft "powdery" brick, stone or mortar. This is an effective, safe, non invasive technique also used on historic fresco restoration work.

I use lime water to soak all my restoration work. A quality sprayer with a good nozzle is very helpful.

To make lime water: simply put about a 1/2 gal of lime putty in a 5g pail, fill with water and mix until it is all dissolved, cover with a tight lid and wait 24 hours or until all the lime has settled at the bottom and the water is CRYSTAL CLEAR. Carefully siphon out your lime water without disturbing the bottom, replace with more water and stir for your next batch. If you do not cover the bucket well or do not harvest the lime water right away, a very thin clear "crust" may form on top of the water which will shatter to the touch and sink to the bottom. This layer is pure calcium carbonate, a thin layer of limestone!!! Harvest ONLY the clear water.  

DEVELOP A PLAN: Select a "wall"  or "panel" to be painted and make sure the substrate is properly moistened but not wet (presence of water). Starting from the top work from side to side, moving downward maintaining a wet edge until the entire area is completed. Lime paint dries quickly and going over dry edges or touching up a spot will inevitably leave an unsightly overlap. Never stop half way through a wall or touch up missed areas on your final coat. On stucco apply alternate coats horizontally and vertically making sure the last coat is applied vertically. On brick apply horzontally, On stone work apply randomly.

Wait 24 hours between coats and moisten substrate before each additional coat. 

 A large brush will enable you to move quickly and avoid the "dry edge issue". For very large areas you will need a good plan of action or additional help to complete the selected area in time especially for the final coat.

PROTECT YOUR WORK: Time of year, temperature, rain, sun exposure and wind play a role on how fast your lime paint job will dry, cure and how well it will turn out overall. It may be necessary to protect your job with tarps or burlap to keep the sun and wind at bay or choose a time of day when the sun is not hitting the substrate, like early mornings or late afternoons and make sure the surface is not warm from sun exposure.

Spring and fall are ideal times of year for lime paint application.  

In summer you may need extra precaution from sun overheating the substrate and drying your lime paint too quickly.

Apply lime paint well before freezing temperatures arrive. 

GO SLOW: Lime paint is very liquid and these brushes are designed specifically to hold a lot of liquids with minimal dripping. Never dip your brush in lime paint more then half way down the bristles, start with 1/4 of the way in, then shake it gently once or twice over the bucket or give it two gentle "slaps" on either side of the bucket walls. Slowly raise the brush to the wall and start spreading the lime paint (move slowly) going over the same area two or three times. Moving slowly allows the paint to be drawn from the center of the brush toward the tip of the bristles and onto the surface. 

MIX THE PAINT OFTEN: Lime paint settles quickly and must be mixed constantly. Keep a sirring stick into your paint bucket and stirr the paint often. If you don't you will end up applying unevenly diluted paint, too thin at the beginning and too thick at the end.

For larger jobs mix all the paint in a large bucket and immediately transfer a portion of paint into a separate container for immediate use. Mix the paint in the large bucket again before transferring some more into the small container for immediate use. This way you won't end up with very thin paint at the beginning of the job and very thick paint toward the end of the job.

You still need to keep mixing the paint in the small bucket as you apply it on the wall.

KEEP YOUR BRUSH DOWN: Always hold your brush in a "bristles down" position (not up) while you are not appling paint to prevent paint migrating toward the heel of the brush. If paint starts dripping from the heel of your brush, unload your brush: shake your brush several times in order to fully unload the lime paint from it, start again by loading the brush with less paint. 

As you get used to it, you will pick up speed without painting the whole neighborhood and yourself in the process!

Be prepared to make a mess when painting a ceiling.

KEEP YOUR BRUSH CLEAN: Stop and wash your brush every two hours or as necessary. Lunch brake is a good time to wash your brush. The brush will perform better when clean and is a lot faster and easier to clean if done a few times a day rather then at the end of the day.

Also, the globs of paint drying up on the sides of the brush will inevitably end up on your freshly painted surface. (not good on smooth surfaces!!)

At day's end wash the brush well with clean water using your hands to gently move the bristles around while submerged in a bucket of water. Try to avoid plunging the brush to the bottom of the bucket as this may kink and weaken the long bristles. Do not hit the bristles against anything hard as doing so also will weaken, kink or brake off the bristles. Shake the excess water from your brush and hang it up side down by the hole on the handle.

TAKE CARE OF YOUR BRUSH: At the end of a job you can additionally wash your brush with a mild soap. I use linseed oil soap or Marseille olive oil soap which will keep the bristles soft and supple, ready for the next job. Always store your brush hanging upside down on a nail or hook throug the hole in the handle. do not store the brush in a bucket, tool box or with the bristles bent or you may run the risk of bending the bristles permanently.

These brushes will last a long time however the bristles will wear down especially when used on rough and coarse surfaces.

Once your brush is no longer suitable for smooth surfaces it will still work well for coarse surfaces. 

After your brush is too worn for lime painting you can still use it for wetting your substrates, applying slurries, washing tools, etc…

Do not hesitate to call for more information!


© fabio bardini 2012