Mortar consistency: hand mixing vs rotating drum mixer
I need a few outside observers on something I’ve noticed over a short period.
I’m laying a small amount of brick, and sometimes I just mix sand / masonry cement in a wheelbarrow, by hand, vs getting out my mixer, mixing, and having to clean that up as well.
When I mix mortar by hand, I mix everything dry first, and then use a mattock to mix in the water until it’s creamy and smooth, using as little water as it takes to get there. It’s nice, spread on toast nice. It holds to the trowel well, stays on the block / brick well, etc.
When I mix it in my concrete mixer, it comes out OK too – it’s workable, and overall satisfactory, but it’s somehow not as creamy smooth as the hand mixed.
My theory is that it takes just a little more water to mix well in the drum mixer, else it sticks to the inside, and doesn’t turn over on itself. I haven’t used a paddle mixer before, so maybe it better replicates the hand mixing action. Maybe it increases the air content, making it more fluid?
Just looking for a few fun theories! Anyone have a similar experience?
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Replies
I'd say that mixing by hand gives you the ability to more accurately achieve the exact mortar consistency you need for laying bricks, and it better "blends" the mortar which otherwise just gets tumbled in a concrete mixer. When I was laying stone and bricks we'd always "finish" the mortar by hand mixing in the mortar pan before use when bulk mixing in a concrete mixer. If you use a powered mortar mixer you'll likely get the results you're after, but there's no better substitute for experience with getting the right consistency than hand mixing.
Daniel