How to Make a Mosaic Coaster from Beer Bottle Caps

After making the trivet my next object of delight is a coaster. I like doing mosaics but instead of using ceramic tesserae I used beer bottle caps. This would make a great gift for a husband, dad, brother or any other beer loving person!

This is my tutorial

1. I decided to make a large coaster 4x4 bottle tops. I measured them and cut a piece of plywood to size. 
2. I prepared the plywood by first sandpapering it, then sealing it with a PVA and water mix (1 part PVA to 4 parts water) I left it to dry. 
3. One side I painted with a coat of black acrylic paint, I left this to dry. 
4. I then gave it a coat of varnish and let that dry over night.
5. The tile adhesive and grout I bought in powder form. I followed the instructions on the packet but added some black acrylic paint to achieve a dark grey colour. 
6. I covered my prepared plywood with a generous layer of tile adhesive. 
7. I arranged the beer bottle caps on to the plywood and pushed them into the adhesive making sure I wiped off any excess from the edges. I left this to dry (24 - 48 hours approx.) 
8. When the tile adhesive was thoroughly dry I mixed up the grout in the same way as the adhesive. I applied the grout thickly with my fingers pushing it between the caps. I wiped the excess off with a slightly damp sponge. Make sure all excess grout is removed because once it's dry it's difficult to remove and you might damage the caps.