I'm going to be placing coping stone over a small wall in my garden.
From what I've seen in videos, you should add a primer/slurry (sbr and cement) to the back of the coping stone before placing it onto the mortar bed on the wall. This is to stop the coping coming loose in the future.
I've purchased a 5L bottle of Everbuild 503 SBR Bond. However I'm not sure what mix ratio to use, I've seen various answers online, some people even suggest adding water in.
What ratio of sbr and cement should I use for putting onto the underside of coping stone?
The following video has what I'm looking for, but the builder doesn't mention how he made the mix (30 secs into video shows it).