Some capitals such as New York, London or paris, are covered with a beautiful and quite hyper resistant street art project called "Invasion", made by... "Invader". This consit in reproducing pixel-drawings (also named as "sprites" in the video game industry) with mosaic and stick it on the walls, in the streets. invader has a simple technique : he is using a glue that is more solid and resistant than the tiles itself, so any attempt to steal these pieces of street art remain unsuccessful. Quite clever!
Knowing nothing about how to do tiles mosaic and where to by the stuff, I started to do some searchs on google image to find an appropriate drawing to convert into mosaic. With a bit of luck I knew I could find one that will exactly fit my wills : not too small, and not to large. A 25x25 tiles mosaic was my absolute limit as it's already involving 625 tiles.
I finally failed in google images, and before starting to convert a bigger image into a smaller one, I did some extra effort to find an original sprite with the size I wanted (pixel design is so well done that I couldn't expect to get the same quality by myself). I finally found the exact 18x18 pixels image I wanted, in a backup of a nintendo GameBoy Advance cartrige. I had to extract the content and one particular design on a splash screen fitted my needs perfectly. I can't reproduce the drawing here as it's strongly under copyright.
Step 1: Sketching the Mosaic - Tiles Count, Color Selection
For my 18x18 mosaic I needed : 20 orange tiles, 26 yellow tiles, 16 black tiles, 63 green tiles and 36 white tiles. I also needed 162 tiles for the background, for a grand total of 324 tiles.
I then started to look for the material. I did researchs, I found mainly the Briare's tiles in every shop, which are very expensive ($180+ for the tiles), so after a few weeks i put the project in standby. One year later, I finally found the appropriate materials at a decent price.
Step 2: Material - 350+ Tiles for Less Than $17
I also discovered a great mosaic shop for professionnals and people. The prices were just a bit higher, but I could find there advices on how to fix my mosaic : I bought a plastic net to fix the tiles on and a tube of Neopren glue, which I recommand, especially if you want to put your mosaic in a bathroom or anywhere outdoor.
I also bought this special paper you use while baking, when you don't want your cake to attach! It prevents the glue to attach on the table where you wil fix the mosaic.
But let's forget the net, the glue and the paper and play with the tiles...
Step 3: Assembly the Mosaic
I first did the mosaic reversed, tiles upside down, to prepare myself to the work. It was very fun and when it was done, I was quite satisfied with the result. You can see on the first pictures than the side with the stripes is the side that has to be sticked on the wall. The stripes are here to make the glue penetrate better.
One it was done, I now had to stick it on a net. When it's sticked on a net, it is ready to be sealed on a wall: you just put your cement glue on the wall and apply the whole mosaic, net included. The net will disapear in the cement of course. If you have large mosaic, you can prepare them on squares of max. 30x30 tiles and assemble them later.
Let's glue the dino baby!
Step 4: Final Mosaic: the Gluing
1 - place the paper on the table. Don't save it, you'll be able to reuse the leaves.
2 - place the net on the paper
3 - put a bit of glue on a tile (stripped side) and place it on the net, the glue on the net's side.
4 - now for the next tiles, put a bit of glue direclty on the net and gantly place the tiles on the glue drops.
...and repeat 4 until the mosaic is finished ! It will need 12 hours+ to dry completely. After that, the tiles are very very well fixed on the net. You can still remove them to correct a mistake, but it not always that easy.
Also think to work in a big enough space with opened windows.. after 324 tiles, I was quite dizzy with the Neopren vapors, I was giggling silliy :)
Gently place your tiles on the net, helping you with a ruler and the net grid to let litle regular spaces between each tile: it's very important that the glue or cement fill this space when placed on a wall, or the mosaic won't be that much solid and resistant.
Now let's see the final result!
Step 5: Result - the Complete Mosaic
I also did myself a Space invader one, just for fun :)
Enjoy, and good work!