Weldbond, when mixed with the water very well and then added to the flashcrete will help prevent the mosaic stone from cracking due to temperature fluctuations. Lots of mosaic artists use it to enhance the composition of flashcrete. But whatever works for one may not work for another.
De
That makes sense because Weldbond DOES stay flexible. I've never used Flashcrete, either, so I didn't mean to sound like I doubted the method, I just wasn't sure 'zackly what you meant.
Rebecca