Cement dust on Indian Sandstone HELP!

[chalklands]

Hi,
I'm repointing my indian sandstone patio with a dry mix (4:1). Tried a test area first, but when I brush the mix into the joints the dust is staining the sandstone. Is this OK?? I've brushed off as much dust as I can. The stone hasn't been sealed.

Any advice would be welcome!

Pete

 

[Spud]

Have you got any pictures ? Don't do any more for now until you get the correct advice on cleaning up what you have done

 

[chalklands]

Have you got any pictures ? Don't do any more for now until you get the correct advice on cleaning up what you have done

Hi,
Thanks for the reply. As it was only a small test area I managed to remove the cement dust with water and elbow grease! Certainly wouldn't want to do that for the whole patio!!

Should indian sandstone be sealed?

Pete

 

[Lithofin BOB]

Have you contaminated the whole stone or a banding effect around the stones?

Photos would be good as Gary suggested ,

Do not use brick clean or hydocloric as this can bring on iron oxide blooms in the stone but also damage ( lighten ) the surface. It depend on the geological make on this type of stone.

If you have just filled the surface capillaries with dust and it has hardened , you should be able to use a suitable ( specifically for this type of stone) mortar / grout/ efflorescence product. Some will be hyd combination acids.

Ensure you do a test on an unlaid stone to determine suitability of product on the stone as well as then testing on one stone laid for dilution of product to remove the issue.

If you were to seal this , you would use an impregnator for external (once fully dry). Be aware that the product will only line the capillary of this type of stone finish not fill it , so you could have the same problem and still need to be careful even if you do seal. I know a lot of the external fitters now gun in the mortar with these textured finishes of stone. Sure the guys on here may have some tips for you

Hope this may help a bit,again photo may tell us more

 

[chalklands]

I'll rethink how I repoint I think.

Talking about sealers, has anybody used this product:
Is it any good? 'The World Of Stone Sealer'. They advertise on this site.[h=2][/h]

 

[TJ Smiler]

Never used it mate....... Lithofin all day long for me (or Fila)

 

[Spud]

fila w68 is a great product for sandstone