The instructions with my concrete mixer recommend adding the water first to prevent the aggregate sticking to the sides of the drum. The trouble is I have ended up with some sloppy mixes particularly small mortar mixes and although I have added more aggregate to get the mix right I have ended up with more mix than I needed. I have not been able to find any info on the proportions of water, I know it can vary due to how wet the sand is already but a ball park figure would help?

Richard