Your hands are the best judge in determining whether it is a well crafted, functional, quality mosaic. It can be very discouraging to to spend hours creating a piece (or spend your hard earned money purchasing a piece) only to watch people grimace as they touch it or quickly pull their hands away from it because of sharp or uneven areas of the surface.
We want to incorporate art and beauty onto a function piece that we use our every day lives. The last thing I want is a surface that scratches or cuts my fingers, or worse still, topples my glass of wine!
Before I address how to level and smooth your mosaic surface, I feel I should briefly mention a couple pointers that both a beginner and novice should always consider before tackling a mosaic project.
First, a bit about your mosaic "base". Contrary to popular belief, a birdhouse, small or large, is NOT the best beginner or novice project. I'm sure many of the novices out there have already that found out. It is far more difficult to mosaic a birdhouse and end up with a piece that has smooth level surfaces and clean edges, similar to heirloom quality pieces. May I suggest that it is best to start with a small table top or tray made of wood or metal.
When choosing a small table, try to select one that has nice lines and curves; such as queen ann style legs or turned legs. It will add to the overall appearance of your mosaic piece! Check thrift stores and flea markets for incredible deals.
Second, before you even being to adhere your first china tile, be sure you have primed and then painted the piece. It is far more difficult to paint your piece after you have finished laying your mosaic design. Be sure to cover the area of the base you will place the mosaic, do take care not to get any of the top coat in that area.
CREATING A LEVEL SURFACE: As you know, not all vintage china pieces are the same thickness, therefore, a press comes in handy. A press is a flat piece of wood or metal. The length and width should be manageable for the size of your base, but does not need to be more than 1/4" thick, just firm enough not to bend or "give".
Now, always place the thickest piece first (the anchor) and level the thinner pieces to it. After you have placed or thickest tile, if the next tile is the least bit thinner, butter a bit of thinset on the back of the thinner tile, then place that buttered tile on the base. Next, hold the press over the thickest (anchor) tile and the freshly placed tile, then gently press down until your "press" rests on the thickest china tile. (Be sure that the anchor is always as near to the center of the press as possible.) To know if you have used the appropriate amount of thinset, after you pressed, some of the thinset will oozed out the bottom of tile, if you don't see any, add a bit more thinset to the piece and press again. With a little practice you will do it with ease in no time at all
I have found that it is best to press one piece at a time, and most importantly, clean off the excess thinset from around the bottom of that tile and off the press. If you don't it may hinder the placement of subsequent tiles. (I use toothpicks to clean off the excess thinset)
Be sure the press size is appropriate for the piece you are working on. I have several different press sizes: 4" x4", and 8" x 4" and my table/count/dresser top base press which is about 18" x 12".
Now, you may think, why not just spread the thinset is a small area and place several tiles down and press them all at once. Been there, done that! The bloody cleanup was a nightmare! The longer thinset stays on the tiles, the harder it becomes. By cleaning the tops of tiles before the thinset underneath the tile has harden you will risk pushing that tile down lower than the other tiles. Also, most thinset do not dry white, so having too much thinset in your grout lines will darken white grout.
For smoothness: when grouting, make sure to push the grout well into all the spaces between the tiles and the base (such as a the side walls of a tray). Also, when cleaning the grout off the surface, be very careful not to remove the grout lower than the surface of your china tiles. Your fingers will be the best judge in knowing if you have removed too much grout, as you will feel the sharp sides of the tile edges.
A sponge or damp cloth will remove too much grout if you aren't careful. I use a small rubber float. I lightly squeegee some grout off the surface of the mosaic with the edge of the rubber float, then I clean each china tile one by one, doing my best to avoid the grout lines. I use a damp paper towel. I find that a soft cloth is too thick and you inadvertently wipe off too much from the grout lines.
Again, because you are working with varying thicknesses, you should expect some rough spots and some sharp edges. With a little practice you will be able to keep this to a minimum.
Before smoothing out any sharp corners of the tile, clean the surface of grout residue, then let the piece dry completely. After the piece has dried, using your fingers and palm, lightly feel around the piece for any sharp tile corners. A quick touch of a dremel will smooth it out. I recommend a dremel over a drill as it is easier to lightly grind off that sharp corner without hitting the grout line or taking too much off the tile. If you don't have one and do not wish to invest in one, see if you can borrow one. Otherwise you might try a metal file.
It is more time consuming to apply these methods, but the end results will be well worth it! You will have made a beautiful, quality heirloom piece that you will cherish and proudly display for years to come! You will find yourself running your hands over the smooth and level surface time and again. You will get loads of compliments and when asked "where did you get that beautiful piece?" you will beam with pride as you reply "I made it myself!" ;-)
If you have any questions, feel free to email me. I will be happy to clarify or provide more detail.
For more topics, instructions and helpful hints, a table of contents is provided at the top of the left margin, entitled "How To's" just click on the topic of interest.