slate staining

[batiling]

Hi all,need some help.I fitted some black slate 600x300 a short while back.
I sealed twice with ltp sealer before grouting with white mapei.After cleaning off and leaving till the next day then cleaning them again i sealed them.The problem is they have a white shadowing on them.I have tried everything to get it off inc ltp grimex,brick acid etc.just wondered if anyone else has had tis prob or has any solutions

 

[DHTiling]

Hi..Some pics would help...

 

[merlecollins]

Sounds to me like the slate wasn't cleaned properly before the initial sealing - you can get this 'blooming' effect if there is any surface dust on the tiles before sealing them....

or

You didn't wash the white grout off sufficiently before the final seal.

Either way the best solution would be to completely strip it back to the existing finish with a product such as HG Remover and start again.

 

[DHTiling]

Blooming is water effecting the sealer..most typicaly topical sealers...this then turns white....

This can happen if the stone was still damp before sealing...

 

[wetdec]

As said sealer has blown slate wasn't dry a good note for anyone thinking of sealing slate outside water ingress through the sides of the tiles will cause clouding as here.


..

 

[Floor_Restorer]

sounds like damp slate when sealed........ I agree with Dave and wetdec. Sounds Blooming aweful........

I would use LTP Power stripper (not a paint stripper) in a strong mix with water and leave for a 20 minutes. Agitate it and scrub the surface with a hard sponge or soft emulsifying pad. Wet-vac it up and rinse. Then LTP Grimex (or Aquamix Heavy duty) do the same and rinse thoroughly. Allow to dry 24 hours....... Then apply LTP Colour intensifier for a deep matt finish or neat LTP Floorshine for a slight sheen.

Hope this helps,

Tom

 

[DHTiling]

sounds like damp slate when sealed........ I agree with Dave and wetdec. Sounds Blooming aweful........

I would use LTP Power stripper (not a paint stripper) in a strong mix with water and leave for a 20 minutes. Agitate it and scrub the surface with a hard sponge or soft emulsifying pad. Wet-vac it up and rinse. Then LTP Grimex (or Aquamix Heavy duty) do the same and rinse thoroughly. Allow to dry 24 hours....... Then apply LTP Colour intensifier for a deep matt finish or neat LTP Floorshine for a slight sheen.

Hope this helps,

Tom

Another LTP user....i used to use lithofin but have switched to LTP mostly this year..

nice sealers.

 

[batiling]

Thanks for the replies,i will give them a go as need this sorting asap ill keep you posted