Help with repointing york stone flags - Repointing york stone flags

[joydivision]

I am having problems repointing an existing york stone patio.
I have raked all the existing mortar out to around 40mm depth and repointed using a 4:1 sand and cement mortar mix.

Problem is the mortor is drying too quick causing the top surface of the pointing to flake away. I think the york stone being a natural stone is absorbing the moisture too quickly.
Before i applied the new pointing i washed the joints out and soaked the stone. The joints vary from 15mm to 40mm wide.

Will using a grano mix prevent this happening?

Any ideas are most appreciated

Cheers

Allan

[mickg]

get a cheap plant spray bottle and lightly spray the joints before applying the sand a cement mortar mix, may need to spray again very lightly an hour or so later to keep it moist

another way is to use one of the gun injecting systems like easipoint, very clean and very fast

Gun Injection pointing systems

[DNgroundworks]

I second the use of easi point, just bought loads of the stuff for jobs i have lined up.

Are you using a plasticiser in the mix?

[joydivision]

Thanks for the replies.

I will take a look at easi point, not used that before, and yes, a constant spray to keep the stone moist has got to help!

Yes used the optamix plasticiser. Do you think that could be a problem?

Cheers


Allan