[karygate]

been doing driveways now for about 18 months and never had to use any chemicals up to yet. anyway did a block paved drive at weekend and it all cleaned great except an area some idiot had been mixing concrete. it came off the black bricks but not the yellow ones as good. what can i use to get rid of the rest any help. the custy was still impressed but i would like to give a 100% result if possible.

[drive surgeon]

brick acid and a chisel and hammer to break the big chunks off.  maybe hot water will help too??

[BDCS]

Wet the blocks then apply the acid, leave to dwell then use the turbo. I use a copper hammer if its thick