Making cement

[imd123]

Yesterday I had the small job of setting a small archway in my garden so needed to mix some concrete. As it was only a small job I used sharp sand instead of soft sand and it hasn't set. can anyone tell me if it will set please or should I dig it up and remix.

Many thanks in anvance to anyone who replies.

[andrewlee]

I would have used sharp sand too. Don't think this will make any difference. Did you use the right proportions? Also, it's been quite cold, so it may take some time to go off properly.

[buildersmate]

Oh yes, it will set OK and you will have no trouble with the strength of it. In fact it will be stronger. Soft sand is used for mortar because it allows the bricks to be positioned quicker - you must have had a hell of a job squeezing the mortar out to the right thickness in the joints. If not setting, more likely the frost has got to it. Did you cover it with sacking or old rags if there is a risk of frost? If the frost gets to it (before it has hardened normally), it won't now set.

[heathfield]

One day sometimes isn't very long in terms of cement setting due to several factors. It could take several days before it starts to become really firm - but chances are it will in the end.