Cleaning mortar off Indian sandstone patio

[Can-do]

Hi All, Just had a coupe of contractors finish off a "Raj Green" random sandstone patio for me. I asked them to match in with the mortar gun applied pointing that I'd used up to that point. I'm pleased with the speed and quality of the laying of the slabs and border brick edge -- but the mortar pointing "bleed" and general cleaning of the surfaces is a mess!!

They've scuffed sand and grit along the joints and tried quick applications of dilute brick acid, but it is still crap.

The brick acid doesn't seem to turn this particular sandstone "orange" as I've heard can happen with indian sandstone?

Any suggestions on the best approach? Has anyone used a "sand blasting" attachment to a pressure washer -- how is the sand sucked into these attachments? Is it fed as slurry from a tank or something or does it go in dry? Would this be likely to work or erode the pointing too quickly?

Any other suggestions or is this going to be a hands and knees job slowly cleaning a joint at a time.

 

[JerryM]

i do feel your agony. having tried very careful pointing myself i'm amazed how difficult it is and now only use kiln dried sand or a dry mix poured/brushed in.

i would have said try brick acid. given this has been tried then a 2nd go does not hold much promise. i'd probably say leave it for a while and see if you can live with it (generally after a few months the weathering generally lessons the impact). also don't forget u know it's their and most people won't even notice it. also there is a good chance of making things worse - i know it's probably hard at this moment to believe this.

if your still intent then have a look where i've learnt all i know on paving etc - the site is absolutely brill. you will probably need to email to get advice on this particular situation though.

http://http://www.pavingexpert.com/home.htm