How To Mosaic Blog

Tag: grout

  • Case Study: Non-Sanded Grout for Mosaics with Incidental Gap

    Case Study: Non-Sanded Grout for Mosaics with Incidental Gap

    For better glass mosaic images, tiny incidental gaps are the way to go. Just forget about grouting and fit the glass as tightly as possible.

    Or better yet, cut the pieces less precisely and use the slight errors in shapes to form an incidental grout gap.

    I highly recommend this latter mode of working because you focus on the visual and make better art instead of getting frustrated trying to cut precise shapes.

  • Nonstandard Method for Removing Mortar in Gaps

    Nonstandard Method for Removing Mortar in Gaps

    Natalija reminded me that she used her cordless drill with a mesh disc to remove the hardened mortar, and that cordless rechargeable tools exist.

    Either we didn’t have cordless rechargeable tools on my home planet, or I was having a stress-induced boomer episode yesterday.

    One of those two things is true, maybe both.

  • White Grout: The Floral Print Aesthetic

    White Grout: The Floral Print Aesthetic

    Artist Masha Leder‘s mixed pique-assiette architectural mosaics using white grout are so good I wanted to name this blog article “In Praise of White Grout.”

    I have been hoping more people would email me some photos of their white-grout mosaic artwork ever since I started posting about avoiding white grout in mosaic images, meaning figurative mosaic that strives to be as life-like as possible.

    Well, art doesn’t have to reflect nature or nature alone.

    This is particularly true of mosaic, which intrinsically incorporates the concept of found object (anything can be a tile) and intrinsically suggests the possibilities of abstract geometric art (when uniform tiles are used).

  • Imperfection as Grout Gap

    Imperfection as Grout Gap

    The Blue Crab mosaic I recently completed is a good example of how to create a grout gap by making use of imperfect cuts instead of spacing the tiles intentionally.

    The “imperfect cut” method makes the process of creating a mosaic faster, easier, and less tedious -first in the cutting and placing of tiles but also in the grouting process.

    Instead of cutting precise shapes with a stained glass scoring tool, cut your glass with a Mosaic Glass Cutter and embrace the slight imperfections in the cuts it makes.

    That “error” will create the grout gap for you.

  • Choosing Grout Color Using Tile Test Swatches

    Choosing Grout Color Using Tile Test Swatches

    Tracy Kaplan recently emailed us a picture of her FIRST mosaic, and it is nice solid work, impressive even, especially considering that her instructor gave her some problematic advice concerning the grout color.  Tracy’s teacher had recommended a chocolate or nutmeg colored grout, but Tracy wisely considered how a dark brown might cause adjacent tree trunks to no longer be distinct and separate.

    Perhaps Tracy’s instructor had meant a lighter shade of those browns, but I still think that those could have caused problems with the adjacent tree trunks.

    Most likely, the instructor only saw a portion of the mosaic without adjacent tree trunks. Tracy admits that she only finished about an eighth of the work during the course and spent many months afterward working to complete it.

    If so, this is yet another example of how artistic advice isn’t one-size-fits-all and can be counterproductive or even disastrous if the advice isn’t specific to a particular artist or even a particular work of art in its entirety.

    Fortunately, Tracy emailed us for advice.

  • Staining Grout With Acrylic Paint

    Staining Grout With Acrylic Paint

    Mosaicists sometimes mix in artist acrylic paint to create custom colors from white grout, but you can also use acrylic paint to “stain” grout after it has hardened (for dry indoor mosaics).

    Like the process of staining wood, “staining” grout with paint is a process of wiping on and wiping off. The paint sticks to the rough grout but wipes off the glass tile.

  • Consistent Grout Gaps

    Consistent Grout Gaps

    In my recent blog article about black and white grout, I wrote the following tip for minimizing the width of grout gaps and working a little faster at the same time:

    If tiles only touch at points but not along the length of their sides, then tiles can be positioned very closely and yet still be grouted. Consider working in this way instead of carefully cutting each tile to maintain a uniform grout gap.

    I need to clarify what I meant by that.

    Uniform Versus Consistent

    Sometimes novice mosaicists will carefully cut each tile to maintain a perfectly uniform gap, which can be a little tedious, and worse yet, they make the gap a little wider than it should be because the artist does not have the experience to visualize what it will look like when grouted.

    I think it is better to work a little less uniform, and to err on the side of being slightly narrow, even if that means tiles occasionally touch at a point or corner. By better, I mean more efficient, less tedious, and better looking.

    All that being said, it is extremely important that the mosaic have the same type of grout gap in all regions. You want to be consistent in your style of gap. You do not want to have loosely executed in one place and tightly uniform in another, nor do you want wide gaps in one region and narrow gaps in another.

  • Black Grout vs White Grout

    Black Grout vs White Grout

    Black grouts bring out the intensity of tile colors while white grouts overwhelm them. Natalie Knox’s Day of the Dead Skull mosaic is a good example of how well black grouts work and how a light colored backer isn’t a good indicator of the mosaic would look with white grout.

    Don’t Be Fooled

    If you lay the mosaic out on a white backer and try to use that as an indication of what the mosaic will look like with white grout, remember this:

    When the gaps are filled with grout, they won’t have all the contrast provided by empty gaps, which have depth and shadow. A lot of white concrete at the same level as the surface of the glass tends to make the colors look washed out.

  • Grouting Case Study (Plus Mosaic Art Worth Seeing)

    Grouting Case Study (Plus Mosaic Art Worth Seeing)

    Artist Sherri Grasmuck created a mosaic facade of Guatemalan women on her house in Philadelphia that is the perfect case study for choosing a grout color.

  • Matching Grout to a Room’s Color Scheme?

    Matching Grout to a Room’s Color Scheme?

    Choosing a grout color is more of a situation where you want to avoid making a mistake that causes the tile to look wrong than it is an opportunity to tie in the room’s color scheme by selecting some optimal color.

    A Case Study

    Should you match grout color to a room’s color scheme? Not necessarily. Making sure the grout color works with the tile colors is much more important.

    Recently a customer emailed us the photo above and asked for advice on how to match the grout color to the room’s color scheme, which includes rich gunstock brown cabinets and paint that is pale green or taupe and a black counter top. The mosaic backsplash itself is made from long gray and black tile in varying lengths.

    Choosing By A Process of Elimination

    Grout colors should always contrast tile colors enough so that each tile is visually distinct. If you were to use a gray grout on this mosaic, the gray tiles wouldn’t stand out as individual tiles. If you used black grout, you would would have the same problem with the black tiles. Since the mosaic is a gray and black color element, a white grout of some shade makes sense. A pure white grout is likely to be too bright, and so an off-white grout that is more or less the same color as the exposed backer between the tiles would be a safe choice.

    Too Clever for Your Own Good?

    What if you still thought that you needed to tie in the grout color to the room’s color scheme? Then you might consider using some sort of terracotta or brown grout in either a light or dark shade. The problem with that approach is that there are many different hues of gray, and not all of these will look good with a particular brown, even if that brown is optimal for the room.

    If you are bent on using some sort of brown or other color for a black-white-gray backsplash such as this, then make sure you take some of the tile with you to the building material store and actually hold the tile up to the grout swatch. That way you can see if the hues look odd together. Avoiding that mistake is much more important than trying to match the other colors in the room.

    How You Know This Is Good Advice

    Notice how the counter top is black, and the stove and microwave oven are black and silver in color. They don’t have any brown or taupe color elements, but they are perfectly at home in the room’s color scheme. Similarly, the mosaic backspash is a black-white-gray color element that needs nothing extra to tie it in.

     

     

  • Black and White Photorealistic Mosaic Art

    Black and White Photorealistic Mosaic Art

    Black and White Telescope Mosaic. Mark’s grandson gazes at the stars.

    Stylized or Photorealistic?

    Mosaic is usually used to make stylized images, meaning images that are simplified in certain ways, and that is done because the constraints of working with tile that only comes in certain colors and can only be cut so small forces the artist to simplify the details. Think about how ancient Roman mosaic faces and figures are outlined like cartoons and how scenes are composed of 6 to 8 colors, and you will know what I mean. I strongly prefer this type of art because it is a dialog between the symbolic and visual aspects of the artist’s mind, and it produces a lot of quirky and interesting details that would never be possible in mere realism.

    BUT, it is important to remember that you can use mosaic to render images in a naturalistic or photorealistic way even if you can’t find tile in all the colors you think you need. First, you can use two colors in place of one. For example, if the teal color you think you need is not available, use small pieces of blue and green tile positioned closely together and rely on the eye blending the two colors together.

    Another means of working photorealistically is to make a monochomatic mosaic or a black and white mosaic, such as Mark did using our 8mm recycled glass mosaic tile when he made the mosaic of his grandson peering through a telescope.

    Note that Mark’s mosaic doesn’t use concentric rows of tiles to convey a sense of motion such as seen in the andamento of most stylized mosaics. Rather, the tiles are treated as pixels in a grid, which is how most though not all photorealistic mosaics are made. The alternative to gridded pixels is to use large irregularly-shaped pieces in a mode similar to stained glass artwork.

    Patterns For Mosaics Made From Photos

    I didn’t ask Mark how he made the pattern for his mosaic, but I know how I would do it:

    I would take the photograph I wanted to use and convert it to a black and white image using Photoshop or another photo-editing software package.

    Then I would enlarge it to the actual size I needed and print it out in sections, and then tape these together on my work table.

    Then I would would cover this pattern with clear contact paper, WITH THE STICKY SIDE STICKING UP.

    Then it just a matter of positioning tiles over the pattern and filling in the design.

    The only question is: Do I put the tile right side up or upside down?

    Upside-Down Tile

    If the mosaic is relatively small. I can spread adhesive on the backer and then press the backer onto the mosaic. In that case, I would want to position the tile upside down.  Of course, this reverses the mosaic design from left to right as if in a mirror. Complete instructions for working in this way are given in my blog article Using Contact Paper To Transfer A Mosaic Design.

    TIP: If you don’t want the above method to reverse your design from left to right, then reverse your pattern from left to right in the photo-editing software that you use to make the pattern.

    Right-Side-Up Tile

    If I would like to work with my tile right side up so that the mosaic is not reversed, then I can use clear mounting tape or opaque mounting paper to pick the mosaic off the contact paper and then press it onto an adhesive-covered backer. This method is commonly used for laying up large mosaics such as murals. Instructions for this method are given in my blog article Mounting A Mosaic On Clear Adhesive Film.

    To Grout Or Not To Grout?

    Grouting can totally change the look and feel of a mosaic, and so this question can be critical for photorealistic work depending on the colors and grout gap used. You can minimize the visual impact of grout by making sure that your grout gap isn’t too large. For most mosaic tile, the recommended grout gap is 1/16 inch, but for 8mm and 10mm tiles, use a grout gap of 1/32 inch.

    For dry indoor mosaic, you can mount the tiles so closely together that they touch and simply not grout the finished mosaic.

    You should also test grout colors before you apply them to the mosaic. The “test” can be as simple as taking some of your tile to the building material store and holding them next to different color swatches in the grout aisle.

    For his mosaic, Mark did exactly what I recommend: he glued some of his tile to a scrap piece of plywood and grouted them with different grout colors to see what they looked like in situ.

    The visual impact of grout color on a mosaic can be evaluated by gluing some tile on a scrap piece of backer and grouting it.

    If that seems like a lot of extra work, the simple truth is that it isn’t. An experiment like that can be done in 15 minutes of gluing one night and 15 minutes of grouting the next, and what is that compared to the amount of time spent on the mosaic itself? Before you dump concrete on something you spent a month creating, make sure you are using the right color concrete.

     

     

  • Shrinking Grout: Fixing Holes In Groutlines

    Shrinking Grout: Fixing Holes In Groutlines

    Grout does not shrink, but it is prone to forming voids and bubbles if it is not rubbed thoroughly into the grout gaps. These holes are easily repaired.

    My friend Fredrik reported a problem while grouting his mosaic portraits of famous rock icons. He described the grout as having shrank in the grout gap.

    Shrinking Grout Detail shows voids and bubbles at the intersection of groutlines. This is a classic problem and indicates that the grout was inadequately rubbed and pressed into the gaps.

    Real Grout Doesn’t Shrink

    The grout didn’t actually shrink, which isn’t possible with traditional grout made from portland cement, sand, and water. (I can’t speak for the newer epoxy-based grouts because we haven’t used them.) What actually happened was that voids were left in the intersections of the groutlines, and these voids got covered with a thin film of grout that then dried out without curing.

    Press Grout DOWN Into The Gaps

    When you grout a mosaic, it is important to press the grout down between the tiles, and to rub and press the grout thoroughly. Otherwise, voids and bubbles will be left down in the gaps and get covered over with a superficial layer grout similar to how a thin layer of wind-driven snow and ice will sometimes form over a crevasse in a glacier. That is why pressing down is important, and you shouldn’t just rub tangentially across the surface.

    You can also “pull” voids into grout by rubbing it repeatedly in the same direction. That is why it is best to rub in circles and to vary the direction of the rubbing randomly.

    Avoid Dry Air: Use Humidifiers

    Fredrik reported that he wasn’t able to able to spend very long pressing the grout into the gaps because it started to harden almost immediately. It takes grout a while to harden, and this hardening happens by binding water not by drying out, but grout can become prematurely stiff and difficult to manipulate if it starts drying out. Since Fredrik was working in Sweden in February, I suspect the air was very dry due to the heat running, not to mention the already low humidity of the winter air. You can avoid this problem by running a humidifier near your mosaic and by doing the grouting away from heater vents. You can also cover the grouted mosaic with plastic kitchen wrap such as the Saranwrap brand.

    How To Fix Holes In A Groutline

    The good news is that it is possible to grout voids and holes and bubbles in a mosaic that is already grouted. The only caveat is that the old grout can suck the moisture out of the new grout before it can properly cure and harden. To prevent this, mist the mosaic thoroughly with water before you begin so that the old grout is saturated with water. Note that the mosaic should not be coated with water because droplets of water or a thin layer of water could interfere with intimate bonding. It really helps to have a humidifier running near the mosaic, and you should start the humidifier an hour or so before you grout so that the old grout isn’t bone dry.

    Before you regrout, you need to expose all the hidden voids and bubbles. You can do this by pressing on the grout with a small screwdriver and vacuuming out all the loose crumbles. Of course, you need to do this in places that look like there is a problem, and but you also need to press in places that look deceptively fine. You don’t want to have to grout a third time.

    I prefer to press straight down instead of dragging the screwdriver because I want to avoid scratching up grout that is fine. If you do get some scratched up grout from your probing, use a stiff bristle brush and a little water on the finished mosaic to buff out the scratches and make them less noticeable.

    If you notice that your grout is crumbly in general, you should scrape it all out and regrout. In that case, you might want to use the grout removal tool.

    Mixing Up Small Amounts of Grout

    One objection to fixing small grout problems is that people don’t want to mix up a whole container of grout and end up wasting almost all of it. The good news is that you don’t have to waste any or at least very much, and you don’t have to be paranoid about whether or not you are adding the right amount of water. You can easily mix up a small amount using a few rules of thumb:

    If you have a small postal or kitchen scale, use 1 part water by weight to every 4 parts dry grout. If you don’t have a small scale, add a little water and mix thoroughly. Stop adding water when the grout has the consistency of dough. Once you have enough water in the grout, mix it thoroughly to ensure even consistency with no tiny lumps of dry material. These can sabotage the grout hardening process.