Hi I used a mix of 1prt cement to 4prt builders sand and a drop (unmeasured) of plasticizer to repoint some damaged areas of pointing. However, the mortar has remained crumbly, I can rub it away with my finger.
What do you think has gone wrong? I did wet the wall (concrete blocks) with a paint brush but could the water have soaked into the wall too quickly? I was a hot day and that wall does get the sun on it in the afternoon.
Thanks Roger
Probably. Brush on 1 PVA:4 water instead of water, and wait till the sun's off it before applying the mortar.
Perhaps the cement has 'gone off', mix a bit more up on its own and see if 'sets' properly.
How long ago did you do it? It remains like this for some days anyway, taking many weeks to reach full strength.
Otherwise, agree with the other comments posted, or another possibility is you carried on working it for too long.
I know it's more difficult to work, but isn't sharp sand the recommendation?
Sounds like the cement had gone off.
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