[Neil Mc Anulty]

What is the best applicator for a deep riven slate floor that has also been laid very poorly

[Jamie Pearson]

I would put if on by hand with a microfiber cloth or a paint brush or both one tile at a time.

Depending in the product you are using you may be able to spray it on with a fan jet and towel off the excess. Can waste product until you get the application rate right.

[Neil Mc Anulty]

Thanks Jamie

[John M Byrne]

Agreed, hands and knees with microfibre. You control it all, sore on the knees though