Recently someone emailed me about how to estimate how many plates would be needed for a medium-sized mosaic of several square feet.
Each type of plate is different in terms of how many useable tiles it will produce due to how round/flat the plate is and how well it cuts. The only way I have found to estimate how many of a particular type of plate I will need is to cut up one of the plates and see how much useable material I get from that one plate. Make sure you look at the pieces critically and not count anything that is too jagged, small or weirdly shaped. Arrange the useable pieces into a rough square, and measure the dimensions. For example, if you get 8 inches x 8 inches, then you know that each plate produces about 64 square inches of tile. Divide that number by 144 to get the square footage produced, which in this example would be 0.44 square feet.
Some types of ceramic dinnerware can be cut with a regular tile nipper, but many types are extremely hard and should be cut with a compound tile nipper, which has compound lever mechanism to multiply the force of your hand.
You can use a hammer to break the plates up into large pieces, but avoid using the hammer to make the individual tile pieces because it tends to crush and splinter the material, and you end up wasting too much of the plate as scrap, especially if there are patterns on the plate you are trying to cut out. A compound nipper is well worth the investment if you are trying to cut out pieces from china with patterns like blue willow or floral prints, and you may want to consider getting a powered tile saw from the building material store if you want to carefully saw them out without losing too much as scrap.
Here are a few more tips about using dinnerware to make mosaic tile:
If you do use a hammer to make the initial breaks, then wrap the dish in an old towel. That will keep shards from flying and help contain the grit and slivers produced by the breaks.
A ceramic and marble file is very useful for smoothing the razor edges of cut dinnerware. Keep in mind that some types of dinnerware are made from some of the hardest ceramic materials known to science, and the broken edges exposed by cutting can be sharper than any knife. Depending on the type of dinnerware you are cutting, something like a marble file may be required before the pieces are useable and safe.
For years, I didn’t own a marble file. Instead, I used a piece of sandstone flagstone and merely rubbed the pieces on that as I cut them. Always remember that you are free to use improvised tools and methods to save time and money and stress!