I am pretty pleased with the job I did on the bathroom vanity top. But--what am I doing wrong to cause some separation of the grout from the tile edges. Only in a few places has this happened but I still have more tiling to do and would like to not see this again. I used non-sanded grout because of 1/16 grout on the larger field tiles. The only place I have noticed the sep. is on the mosaic area that has 1/8" grout. The mosaic runs between the larger tiles.
My guess is that the grout didnt shrink, but was washed out too much during clean wiping. I am leary of unsanded anywhere except tight joint stuff like granite or DAL 4X4. I would have used sanded on those 1/16" too.
P A H : you could mix more NS grout, moisten the sunken grout and try to add more. It may bite in it may not. you could trim out the sunken areas with a utility knife and re-grout them deeper.
mix non sanded by hand. It should be the consistancy of room temp. adams creamy peanut butter.
Also you said you have more tiling to do. If you have a 1/16 to 1/8 in joint sometimes you can mix the sanded and non-sanded grouts to make sure there is no shrinkage effect. This may change the color slightly but its works great.
A lover of tile and the art of tile setting,