Cement veneer - Wet grouting

[renovator]

Are there any products available that will readily remove the veneer cement left over from a patio that has been previously pointed by the wet grouting method? The slabs appear to be of a cement based flag type. Mick.

[Tony McC]

Cement remover, aka brick acid, aka etching fluid, aka patio cleaner. It's all basically hydrochloric acid at different 'strengths'.

You need to be careful, though. Not only will it eat the cement, it will eat the upper surface of the flags and may even affect the colouring. Some tips...
<ul>
<li>Test a small discreet area first.
<li>Dampen the surface with water before applying the acid wash.
<li>Dilute the acid to a max strength of 4%, preferably 3% and use two or three applications at that low strength, rather than one or two goes at 5-6%.
<li>Wash off between applications.
<li>Use a stiff brush to encourage the cement film to come away from the flags before the acid gets to the surface.
<li>
<li>Don't expect miracles!
</ul>

[renovator]

Thanks for the advice, have got some cleaner from my local builders merchants that is doing the job.