A common mistake made in first mosaics is a variation in the width in gaps between the tiles which results in the details of some areas being “lost” in concrete once the mosaic is grouted. The problem is a little sneaky because it isn’t visible until the mosaic is actually grouted, and so an artist can be experienced in other media and still get caught by this. In my opinion, it is one of the most subtle points in the mosaic learning curve.
Consider the detail in the photograph below:Rose detail from artist Dorothy Stucki’s “To Begin and End with Nothing”
The artist wishes to depict the angularity and variability in the shapes of the rose petals, and has done good job in doing so. However, some of the gaps between the petals are almost as wide as the tiles. This means two things in terms of how the mosaic will look once grouted:The rose will not be as colorful because once the gaps are filled with concrete, about 50% of the surface area of the rose will be dull concrete at the same height as the red glass and just as visible. Gaps don’t look nearly as wide when unfilled. That is the crux of how the problem sneaks up on experienced artists. The rose will look conspicuously different from the tiling around it because it will be the only place where the surface area contains so much concrete.
The good news is that the problem is easily fixed. I have written an article about how to remove and replace glass mosaic tile to change a design before grouting.
Another relevant point is the importance of displaying and studying your mosaic before you grout it.
In my previous post, I wrote about how to remove and replace glass mosaic tile to make changes to a mosaic before you grouted it. I also explained why it was good to display the mosaic for a few weeks before grouting so that you had a chance to see the mosaic as a whole with a fresh eye before setting it in concrete.
But writing this got me to thinking about a common problem that isn’t visible until you grout the mosaic, and that got me to thinking about all the ways in which people “ruin” their mosaic in the grouting process. Fortunately, the mosaics aren’t actually ruined, and there are solutions to each problem, at least in the vast majority of cases.Conventional Grout, Not Epoxy Grout
Keep in mind that all of the mosaic advice on my websites is written for conventional portland-cement grout. If you are using one of the new epoxy-based grouts, then some of what I am recommending might not be possible or might require more work.Ways Mosaics Are “Ruined” By Grouting
Here are problems commonly reported after grouting a mosaic:My mosaic is covered with a dull gray or white haze. I let the grout harden on top of my mosaic before I could get it off. There are specks of grout in the pits and voids of my glass tile. My grout is crumbling and falling out. The grout stained my unsealed stone or ceramic tile. My grout is not as dark and colorful as it was when it was wet. I used the wrong color grout. My tiles seem smaller after grouting, or my mosaic isn’t as colorful as it was.
NONE of the above problems mean the mosaic is ruined permanently, and most are relatively simple to fix.A Dull Gray Or White Haze
Grouting involves pressing wet grout onto the surface of the mosaic, working it into the gaps
thoroughly, and then scraping off all the excess. But that is just the initial phase of the grouting process. The second phase involves cleaning and hazing, both of which must be done with care not to erode the grout from the gaps or moistening it with excess water.
If your sponge or rag contains too much water, then you wipe off the top layer of colored grout in the gaps leaving only the sand, and then the grout will look lighter than intended when it is dry. That is why installers only clean the tile so much when the grout is still wet and curing. They err on the side of caution and leave a thin residue that dries into a haze. That is why the process of buffing a freshly grouted mosaic with a clean rag is called “hazing.”
If you leave a little too much residue, the haze might be more substantial and not wipe off with a rag. If so, no worries. Simply use a Scotchbrite pad or wire brush to scuff away the haze. Do this process wet using a spray bottle to mist the mosaic to avoid breathing dust.The Grout Hardened Before I Could Scrape It Off
This problem can be thought of as an extreme case of the problem discussed above. If you have excess grout hardened on your mosaic, it can be removed. Concrete can be eroded relatively easy if the total surface area isn’t excessively large. For this situation, we has a wire brush of the type used to clean welds, which has thicker and stiffer bristles than the wire brushes used for cleaning barbeque grills. We mist with spray bottles, and once the excess is worked off, we finish up with Scotchbrite pads and rags as described above.Specks of Grout In Pits
Sometimes stained glass and even molded glass tile will have pits in the surface that were bubbles when the glass was molten. Naturally grout fills these voids just as it does the grout gaps, and it doesn’t wipe off. Often times, people won’t notice the problem until the grout is cured and lighter. This is a trivial problem. Mist the mosaic with water and use a dental pick to clean out the voids. You can also use a light gauge wire brush if the problem is fairly widespread, but take care not to erode grout from the gaps.Crumbling Grout
Concrete hardens by binding water, not by drying out. If you doubt this, then think about how concrete can harden underwater. If you let your grout dry out when it is curing, it will be soft and crumbly. Cover your mosaic with a plastic trash bag if the AC or heat or sun is making the air dry. The grout will also be soft and crumbly if you don’t add enough water when you mix it up. Follow manufacturer instructions on the package.
If you have crumbly grout, then scrape it out with the grout removal tool we sell or an old screwdriver and regrout the mosaic.The Grout Stained My Tumbled Stone or Unglazed Ceramic Tile
Porous materials like tumbled unpolished stone and unglazed ceramic tile can be stained by grout. We prevent this problem by wiping the mosaic with a rag dampened with Tile and Grout Sealer, such as TileLab brand a day BEFORE we grout. We are careful not to get any sealer in the gaps where the grout will need to bond to the sides of the tile, and we have used small artists paint brushes for this purpose.
If you didn’t know to do this, all is not lost. You can sand off the stained layer with 80 grit sandpaper followed by 120 grit and finer grits if needed. Of course, you don’t use sandpaper. Like any craftsperson in the know, you buy the belts used for belt sanders and cut them up. The belts don’t cost much more than sandpaper, but they last literally a hundred times longer.
Also, you should wet sand this using a spray bottle to mist and wear a dust mask to avoid breathing the silica dust.The Grout Is Lighter Than It Was When Wet
Grout will always be lighter when it is cured and dry, no matter how dark it was when wet, and this is particularly true for dark colors like charcoal black.
There are two solutions:
The first option is to seal the grout with a sealer known as a “stone enhancer” instead of a regular tile and grout sealer. However, enhancers are invisible pore sealers just like regular grout sealers and not a coating that actually forms a gloss layer over the top of the grout. That means there are limits to how much color you can bring out with an enhancer.
If you need an extra dark grout gap, then consider painting it with artist’s acrylic paint instead of sealing it. Glass tile is non-porous, so the paint should wipe right off the glass and stick only in the porous grout. Of course, you should only do this for dry indoor mosaics. I don’t want to get any emails from dodo birds painting the insides of their tile showers.The Wrong Color Grout
Grout can really change the look of the mosaic, especially if you use wide grout gaps. Grout works best when it serves to separate the tiles visually like a thin pencil line in a watercolor painting. That is why the best choice of grout color is usually a medium gray, unless you are using gray tile. It’s important that the grout color CONTRAST tile color instead of matching tile color. If it matches the tile color, then the tiles will run together visually and not stand out as individual tiles, and the mosaic usually looks poorly as a result.
There are two alternatives when you use the wrong color to grout your mosaic: Scraping the grout out with a grout removal tool or painting the grout with color as described above.My Tiles Seem Smaller or My Mosaic Isn’t As Colorful
The grout gap always looks wider once it has grout in it. It also has no color until you fill it up with concrete. In an ungrouted mosaic, the colorful sides of the tiles are visible. That means a mosaic with wide grout gaps is particularly susceptible to looking duller when grouted.Smaller Grout Gaps For Smaller Tile
If you use small tile or small pieces of tile, then remember to use a correspondingly smaller grout gap. Sure, a 1/16 inch gap is standard, but if your tile is 3/8 inch, you probably want to use a smaller grout gap if you are rendering the details of an image instead of merely tiling a wall.Rounded Tops
Another solution is to not fill the grout gap all the way to the top. This is particularly important when using tile with rounded corners or a rounded top surface. Think of it this way: If you let only the peaks of the tile show above the grout, then your mosaic’s surface area will be mostly dull concrete instead of colorful glass.Solutions
If you haven’t yet grouted a mosaic with wide grout gaps, consider reworking the areas with the widest gaps. Often that isn’t practical because the problem is widespread, so the remaining option is to rub the wet grout off more aggressively than normal when you scrape away the excess and try to erode some of the grout from the tops of the gaps.
If you have already grouted the mosaic, then consider using the grout removal tool to scrape some of the grout from the tops of the gaps. This is particularly effective when the tile used has rounded tops. If you get some of the grout off the slopes of the tile so that more of the faces are showing, then the mosaic can become a lot more colorful. Again, this isn’t as useful an option if the mosaic is wet or outdoors. In those cases, you would have to pay close attention and make sure that enough grout remained to keep the out moisture, and you would need to reseal the mosaic.Don’t Give Up Hope
It is an act of faith to dump wet concrete on top of a detailed picture that you just spent weeks making by hand from tiny pieces of glass. Not surprisingly, most novices expect the worst when anything goes wrong or appears to go wrong, and they are usually convinced their mosaic is ruined. This simply isn’t true.
The Pace of Art
Taking time to reflect on what you are doing can be the difference between producing a mediocre work of art and a great work of art. All too often, we miss opportunities to make something really wonderful because we are too concerned with just getting the job done. When we work on our art at the same pace that we run errands and do other tasks in the modern world, we end up making artwork that is more product than art.It Takes Time To Really See
Like many artists, I have trouble seeing a work of art as a whole while I am actively working on it because I am too focused on the details of specific areas or specific aspects of the work. Ironically, these details usually don’t turn out to be nearly as important as something I’m not even paying attention to at the time. That is why painters let “finished” paintings hang out in their studios for a few weeks before applying the final varnish. After you are supposedly done is when you usually see what needs to be done.Display Your Mosaic Before Grouting
I always display a mosaic in my studio for at least several weeks before grouting it. Before things are literally set in concrete, I want to look at the mosaic with fresh eyes and really see it for the first time. Most often I notice little things, things that might be good to do on the next mosaic or things that aren’t significant enough to justify the work required to change them. But other times I notice fatal flaws, things that make all the difference in the world and have to be changed. What do I do then?
I have written a post about how to remove and replace glass mosaic tile to change mosaic designs before grouting.
If you have already grouted your mosaic, you can still use these instructions, but you will first need to remove the grout using a grout removal tool, which is normally used to scrape grout from the gaps between glazed ceramic tile. It may take a little more care with glass, but this tool can be used to remove grout from mosaics made from small pieces of glass tile.How To Remove and Replace Glass Mosaic Tile A Caveat
Glass tile doesn’t usually pry up in one piece. If you are able to get most tiles off in one piece, then there was probably something wrong with your adhesive or mortar. Expect the glass to come up in sharp pieces and slivers and not be reusable. Never chisel the glass off by banging at it forcefully. If your scraping tool slips past the tile being chiseled, your knuckles and wrists will be headed straight toward razor sharp teeth mounted in concrete. Wear leather work gloves. I wear my welding gauntlets.Moisture Helps
If the mosaic in question was made with a white PVA adhesive such as Weldbond, then I use a moistened cotton swab to selectively wet the edges of the tile, taking care not to wet the surrounding tiles too much. Note that if the Weldbond has had several months to cure, it may be more water resistant, but you should still apply water. Keep plastic kitchen wrap such as Saran Wrap over the tile and reapply moisture as needed to let the glue soften for an hour or two.
If the mosaic is an outdoor or wet mosaic made with thinset mortar, moisture doesn’t really help. For thinset mortar, it is best to make any changes within a week at most. Thinset is hard and tough and it really grips the glass once it has had a chance to fully cure.Prying Tools
I usually use a medium size standard screwdriver to pull the tile up with a combination of scraping and prying. Notice that when you attempt to pry the tile up, you tend to use the surrounding tile as a fulcrum on which to rest the screwdriver, and this is a problem. It can crack or even shatter the surrounding tile, and it is likely to do so because the glue is usually stronger than the glass. Fortunately, there is a simple solution: Lay a Popsicle stick or ruler over the surrounding tile and use that was your fulcrum. Of course, you will need to use one hand to keep the ruler from sliding back slightly as you pry. If you let the screw driver slide the ruler away, it will make contact with the tile underneath and damage them.Damage To Backers
Plywood and concrete backer board aren’t as strong as Weldbond and thinset mortar, so they will sometime delaminate when use start prying and scraping and you end up pulling off the top layer of the backer. If this happens, don’t panic. Plywood can be patched with a mixture of sawdust and Weldbond, and concrete backer board can be patched with thinset mortar. However, you can minimize the possibility of this happening in the first place by attacking the tile from multiple angles instead of just working from one side.Safety Requirements
When you pry up glass tile that has been glued down, sharp pieces can break off and go flying across the room. (I try to keep my leather work glove over the tile to prevent this possibility.)
You should wear safety glasses with side shields. You may even want to wear the plastic safety shield masks that are made for working with power tools. You also want to make sure anyone else around your work area has proper eye protection.
Another issue is the tiny sharp slivers of broken glass. Keep a vacuum nearby and use it periodically to clean the work area. It is always the tiny invisible slivers that cut you when you wipe the work surface clean with your hand. Use a vacuum instead.
Wear leather work gloves and be cautious of jabbing forcefully at the tiles. Use deliberate motions and think about where your hand will be headed if the tool slips off the tile: The freshly broken glass is sharper than any steel razor and it is mounted. If you punch your hand or wrist into it, you will be going to the emergency room in all probability.
You Can’t Force Freshness
To make it as a professional artist, you have to keep your art fresh and always be enthusiastic about working on it. The easiest way to do that is to keep a variety of media in your studio and move between them as needed.
Yes, you need to have discipline and focus and stick to a craft over time to develop any depth of skill in it, in mosaic or in painting or whatever your preferred medium of art happens to be, but sometimes you need a break from the routine to have perspective on what you are doing. Sometimes you need to make little clay sculptures instead of mosaic. Or work with paper cutouts or collages from old Kodachrome photographs from 1960’s National Geographic magazines. Sometimes the most important work you can do is to not bang your head against blockages or monotony.The Importance of Play
As an artist, you will most likely live on small commissions and day jobs and can’t afford to let too much time go by in an unproductive way. Most likely you are painfully familiar with how competitive the world is and how much economic incentive there is to always by sharpening your skills. The question is how to take a break without taking a break, and the answer is alternative mediums.Legos Tonight
I play Legos with my 4-year-old son every day after I pick him up from preschool. We built up our collection of Legos from a few key starter sets and ordering specialty kits like wheels and doors and windows as needed. I am careful to avoid anything that is too theme specific, especially franchise themes like Star Wars and Harry Potter, and stick to generic Legos instead. I want to show my son how to build things he imagines from generic components, not make copies of things that are already saturated in video and other commercial media.Used Bulk Lots on Ebay
The best source of Legos turns out to be eBay, where you can buy them in 10-pound and 20-pound bulk lots and get thousands of used blocks and components for the price you would pay for just a few hundred new pieces. Also, the selection of blocks in the used bulk lots is much more diverse than what you could find in any new set because these bulk lots contain blocks from countless sets of different themes from different years, many of which are discontinued and no longer available. The latest bulk lots I bought probably contained blocks from at least 40 to 50 different sets, and about 50% of the blocks were components I had never seen before: shafts, brackets, panels, hinges, beams, axles, etc. The color selection in these used bulk lots is also more diverse than what you find in a new set for exactly the same reason.How To Clean Used Toys
One concern about buying used toys is that they can be covered in several decades worth of filth, contagious germs and little-kid stickiness. Since Legos and most contemporary toys are plastic, it is very easy to clean them by soaking in a basin of warm water with a small amount of chlorine bleach added. We use one of our large plastic recycling totes and a colander to process the whole set in one batch. The colander is more or less required to catch all the hundreds of tiny pieces.
If you are buying toys to make assemblage sculpture, you should also consider cleaning them in a batch before starting work, although I am referring to newer contemporary toys and things that don’t have an interesting patina that defines how the object looks. Antique metal toys and even plastic toys from a few decades ago often have some rust or dirt or patina that can’t be cleaned off without changing if not downright ruining the look of the toy. Make sure you avoid the bleach bath for these type pieces and give them individual attention. I have even seen artists paint a layer of thin acrylic over patinas and dirt to make sure it didn’t come off.My Latest Lego Creations
Enough babbling about how to make art! Here is what I made last night. Let the bidding begin at one million dollars. That is how much fun I had making them. Note that the hoist on the crane works, as does the magnet, and all of these creations were built from generic components without a plan:Lego Crane Truck Rear View Lego Crane Truck Front View Lego Asian Taxi Lego Amphibious Duck Vehicle Lego Adjustable Camera Boom Mounted on Rolling Swivel Platform Lego Jet Car