Help! - mortar!

Soni · Post: # 18072Post **Soni** Mon Apr 23, 2007 6:54 am

I finally finished my patio, and pointed the joints yesterday.

I originally started to point the joints with slightly damp mortar, the mix was just right with regards to water - as it was not runny, but instead like butter.

However, as i have 200 slabs, and as it took me around 15-20 minutes just to do one slab, i decided it was too time consuming and that i would use the brush in method instead - so i disgarded the damp mortar i mixed up and mixed up some more mortar without adding any water for the brush in mix.

Now, i have had disasterous results using this method around 6 years ago, whereby i used a wet mix to brush into sandstone slabs and ended up the following day with SEVERE staining and spent nearly 1 month afterwards using acid and cleaning materials trying to clean them but it ruined the surface.

This time however, i made sure that it was bone dry with no water added, and although it was a pain to get it all off the slabs afterwards - as i used building sand, and a 2:1 mix (as the building sand bags looked bigger than the cement bag) and it was so so powdery - i seemed to manage to get it all off in the end.

However - this is my problem, this morning i have checked, and although there is no visible staining, the cement still hasn't gone off (i finished brushing in around 18:00hrs yesterday) and i'm worried that if it rains it may all pour over the slabs and stain????

Also - i've noticed that although no cement is visible, if i touch the surface of the slab with my finger then i am left with a white powdery residue? Could this amount cause staining?

I really don't want these slabs to stain - so please can somebody help me out here and advise me what to do?

Thank you in advance..

Mon Apr 23, 2007 7:28 am

you should have used romex rompox or patio,these pavement mortars leave no satining and a nice equal finish,if you have a hose you could go round and mist all the joints to try and get set on them but really,the dry pointing method never really lasts the course
cheers tony

Soni · Post: # 18075Post **Soni** Mon Apr 23, 2007 8:53 am

lutonlagerlout wrote:you should have used romex rompox or patio,these pavement mortars leave no satining and a nice equal finish,if you have a hose you could go round and mist all the joints to try and get set on them but really,the dry pointing method never really lasts the course
cheers tony

do you reckon the powder that i mentioned that i get on my fingers when i touch them could cause staining? Even though there is nothing visible to the eye?

Also, lets say that the pointing 'does' go off eventually, if it ever comes out in the future and goes on the slabs can it still cause staining?

Stuarty · Post: # 18089Post **Stuarty** Mon Apr 23, 2007 6:49 pm

it wont stain once its gone off, but if it was bone dry it wont go off, it needs a little dampness.

TheVictorianCobbleCo · Mon Apr 23, 2007 8:31 pm

Hi - you not going to like this, but then you're not going to like your grouting after a few months either, reconsider by either taking the Romex route or dig out out the swept grout and go back to doing it properly, I know its a shlep but you'll get better as you go along, you dont have to do it all in a day. Sorry to be such a killjoy but you wont regret it.