Replacing a couple of damaged patio slabs today, laid on a sand bed (I'm guessing 10-1 with cement).
I don't do a lot with mortar. I assumed a fairly dry mix would be best, helping to take the weight of the slab. Wrong!
The sand & slab seemed to suck the moisture out, so tapping the slab level & flush was almost impossible.
A fairly sloppy mix did the trick OK.
Is this what a mortar plasticiser is for? Would that have kept the moisture in the mortar? If not, what does a plasticiser do?