Strange external breeze block question

[angiepooos]

Hi there, I'm an artist painting a Victorian brick wall effect on an outside breeze block wall. I know what paint to use, and have completed many similar painted projects, but never needed to alter the surface. So I'd be so grateful for any advice you can give.

Bricks being smaller than blocks, I'm looking for:-

1. a putty consistency product to fill in some of the grooves between courses of the breeze blocks, suitable for an outside wall, and
2. a tool to create a groove to indicate a mortar gap.

Many thanks
Ange

 

[tomfe]

Abigale, if you are in the UK and not Nashville, then you might just be best rendering the wall and while it's still green (not set) add your texture and grooves. You can get a tool which cuts the grooves to match mortar lines or you can make one out of an knife.

Or use masonry filler