Medium Grain Plasters, Lime-Based & Acrylic, which is better?
Medium Grain Plaster is smooth, yet textured like true sandstone and can resemble the cut stone used in the old buildings found in Europe. Protek offers you Lime-Based (Marmorino Carrara) and Acrylic (Carolina Sandstone) versions.
Its most common use is to reproduce antique or polished stone as it contains clay that can be both tinted with universal colorants or washed with pigments.
The essence of true stone colours and textures can be reproduced effectively using these methods described here in this blog. The question we often get is, “Which is better, lime or acrylic?”
Marmorino Carrara Medium Grain Lime Plaster
Marmorino Carrara Medium & Coarse are traditional Italian plasters utilized to produce Istrian Stone or Dense Limestone design styles.
They are becoming very popular plasters in North America. Marmorino Carrara creates a stone effect with striations and reflective specks to diffuse the light on walls, columns and architectural features.
Medium grain Lime Plasters when applied go on a set point (the moment between wet and dry). Once this occurs the plaster goes into a plastic state, called by some ‘putty like’ that can be smoothed without fear of delamination or residue stickiness. Using pressure on the trowel it will crush into a smooth surface and, if required leaving pitting, if the texture permits.
Preparation of the substrate:
In order to do a correct application, the surface must be completely smooth, dry, and without dust or moisture. Use Protek Sharktooth Primer applied by roller or brush, which helps adhesion.
- Sharktooth Primer is a white, water-based primer containing extra-fine ground expanded glass specifically designed for acrylic and lime-based plasters.
- The VOC content is very low- 20g per liter.
Apply it to traditional Concrete, Concrete Based Plasters, Gypsum and Plasterboard.
- In the case of old and previously painted surfaces, apply one coat of Texprime.
- In case of powdery deposits, or surfaces coated with wax or soap, it is necessary to sandpaper the surface before applying a coat of Texprime or maybe two.
Applying Marmorino Carrara Medium Grain Lime Plaster
Remove any excess water in the bucket before use. Once the primer is completely dry (after 6 hours) apply an even first coat with a plastering trowel. Consumption for the first coat is 60 sq. ft. per 3.78L.
The idea is to create a smooth, absorbent surface so the subsequent coats can bond.
- When the first coat is dry (approx. 12 hours),
- Apply a second coat homogeneously, creating an even surface by compression. The amount of product for this coat is 80 sq. ft per 3.78L.
- After an hour or less, proceed with a wet-on-wet application in order to compact the grains in the plaster.
- Polish the surface as it is drying with the trowel at a 45° angle to the surface.
- The gloss is the result of pressing the trowel onto the surface with the correct inclination 25°. Let the surface dry for at least 48 hours before applying wax.
- Apply a coat of cream wax with a trowel. Remove any excess wax with a cloth (TNT, cotton, microfiber).
- Proceed to the polishing stage using the trowel at a 25° angle firmly applying pressure.
Thanks to its great versatility, Carrara may be applied as described in the traditional application
method; alternatively, in one coat combined with other products such as Classic, or with special additives as salt and pepper to obtain the typical speckled effect.
Technique
Applying a blocker (wax that allows recoating) coloured glazing can be used to accentuate the varied layering.
Application
Very useful when aging or adding another layer of color only on a textured finish as the image below.
Technique
Applying a blocker (wax that allows recoating) coloured glazing can be used to accentuate the varied layering.
Application
Very useful when aging or adding another layer of color only on a textured finish as the image below.
For a smoother effect and velvety touch, in light colored surfaces, apply Savon de Marseilles after at least 48 hours when the surface is completely dry. Apply it with a trowel smoothing until complete absorbed. Proceed by polishing the surface with a dry cloth (TNT, cotton, microfiber) carefully removing any possible marks from the soap.
8ft high wall by 15 feet
The detailing and depth of movement is astounding as the surface is completely smooth
yet has lots of detailed visual texture.
Application
The technique achieved using Carrara and a lot of skill.
If applying a glaze over this lime-based plaster, it needs to be blocked, so manipulation of the glaze is possible without penetrating the surface. For this purpose, we use a wax called Flat Wax. Like a varnish, it will block and seal the surface. Texturline Flat Wax which comes in a paste form, drying clear. Available in quarts and gallons, a quart covers 250sq. ft. The glaze we recommend is Easy Glaze, a flat glaze that can be burnished when required, also covering 250 sq. ft. per qt.
The image above is a double-layered texture with a colored wash and waxed.
Create an old plaster wall that resembles a marble that has aged multi color plaster note.
NOTICE how the colors remain in separation and not blending together everywhere on the surface.
To create a distressed marble look, several colours can be applied simultaneously. The technique is to apply several colours without intermixing them too much. Lay 2 or 3 colours without smoothing them, just put it on thickly and wait until is sets up, about 10/15 minutes. Taking a clean trowel, crush the product until you get a smooth surface with blended and non-blended colours. Then wax as usual and polish the resulting effect. If further aging is required tint the wax, and trowel over, and depending on the colour you can distress at will.
Distressed Look: Cracking
Marmorino Carrara Coarse
Coarse Marmorino presents an alternative in a lime-based product. It has been specially designed for maximum simplicity (single coat) and versatility; with it you can create smooth to intensely textured effects. Installation instructions are the same as Carrara Medium but the texture will be more pronounced.
Carolina Sandstone
An innovation in acrylic plaster, Carolina Sandstone is a truly remarkable product for interior use, which gains new applicators every day. It comes in paste form to accommodate the varied requirements distressed plaster.
The classic application simulates Marmorino Carrara lime plaster designs.
Examples of Carolina Sandstone simulating Marmorino Carrara
- When cracked walls are needed, dilute it at 15% water heat with a hair dryer or use Aquaglass crackle medium in the areas cracking is needed.
- For embossed stencilling, use the paste to fill the stencil to create a relief. Allow it to dry, Stonewash the whole area, then sand the high spots on the stencilled relief.
- It is ideal for creating blocks, and can be used in combination with our Stonewash pigments or glazes.
Sealing is generally done using our dead flat varnish Zero Gloss.
Surface Preparation done in the usual way, filling holes and sanding as required. Prime the surface with Protek Sharktooth Primer, and allow to dry 6 hours.
Depending on the look you want, apply the first coat with a trowel. Use a thick one coat application. Try to spread the plaster evenly as possible.
On the second coat, for the classic look, trowel on, tightly compressing as you advance across the surface. Best to use the Co Me Bianko trowel because it leaves no grey marks.
Medium Grain Plaster Blog (continued)
An innovation in acrylic plaster, Carolina Sandstone is a truly remarkable product for interior use, which gains new applicators every day. It comes in paste form to accommodate the varied requirements distressed plaster.
The classic application simulates Marmorino Carrara lime plaster designs.
The varied coating options open to you are:
- Flat Aspect Using Zero Gloss Varnish
- Colored Distressing Using Glazes
- Washes Using Stonewash Pigments
- Waxing Will Get A Honed Stone Effect
