(Q)I have been using powder grout when mosaicing with ceramic tiles. I found that after a few days, a few small hairline cracks appear. Can anyone offer a solution?

(A) This has happened to me when I have worked on table tops and then either the base reacts or I move it before it is set (I'm not sure which causes it). What I have done is to mix some very thing grout and pour into the cracks. It worked fine for my small projects so fa

(Q)I've just completed a mosaic and I find that the grout I have used is too light in colour. As a result it has spoilt the effect of the design. Does anyone have advice on how I can darken the grout please?

(A) I've used regular acrylic paint to highlight grout (gold paint on black grout, rubbed off), and assume you could do the same to darken the grout. Also, have read in several books that others have used acrylic paint to completely color white grout. I'd do a test first. Sheri Hooton

(A) According to the book, Mosaics with Natural Stone, by Walter Lauppi, Pg. 34. COLORED MORTAR Any mortar can be colored by adding pigment dissolved in water or by using colored cement in the mixture. Use only earth colors, such as terre verte (earth green), raw or burnt sienna, raw or burnt umber, English or Indian red, vine black, etc. Chemical pigments are decomposed by cement. The color pigment or colored-cement is best mixed with water and added as a liquid to the finished mortar. An important point to remember in adding pigment is that the color will appear 50 per cent brighter when dry. (Author uses term mortar for grout.) The point the author is trying to make is that pretty much any color pigment will work. Chemical pigments, such as in liquid paints, will decompose and leach away over time, due to a chemical reaction caused by the cement. Sorry this doesn't solve your current dilemma, but it's good information to know. MM:(useful info from Cat in SC

(Q)Is there a supplier of colored grout in the United States?

(A) I have used this grout for an out door wall mural in zone 4. comes in lots of color sanded or unsanded, latex-fortified. made by DAP the product is called: durabond ceramic tile grout. might check your local hardware store. they can order it for you or check for tile suppliers in your area. ask for a color chart. Pamela, Oswayo, Pa.

(Q)I'm a mosaic artist who has been doing mosaics for many years, and I have a problem that has come up repeatedly. To one degree or another, I have problems with dark grouts. Recently I tried a new product from Tile Lab, that is supposed to be an excellent sealer for outdoor works. However, when the mosaics got rained on the other day, and I saw what happened to the color of the grout, I was very upset because the black grout which was mixed with latex instead of water, prior to using the sealer a week or so later, turned absolutely grayish-white on the surface! I've talked to the company and other industry professionals and no one can tell me a thing! These pieces are done on cement. Outdoor use, and I have no idea what is the cause, or if there is an easy surface remedy to return the surface to black? Public show coming up, as well as city looking at work for future project, this can't be happening!! Anyone know what's going on? Please reply in a hurry!

(A) I have also had this problem and it was finally discovered, after a lot of attempts, that the dark grouts were being coated with a whitish coating by the nature of the hard water chemicals in our water source. We had only recently moved into our studio... This coating never appeared in our light grouts for obvious reasons. Adjusting the water was the solution...I have never had a problem since!! I do not know the quality of your water source but this was our experience with that whitish coating. I never successfully fixed the grout of the affected mosaics. It was an expensive live-and-learn experience!!! MaryAnn Jagg




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