bonding float, when to scratch?

[raydar]

In the middle of bonding my first wall (going to be a late night) and so far so good after feathering off, just waiting for the bonding to set a bit before removing batton and filling.

The problem I have got is i am not sure when I should devil/scratch the bonding. I am worried that if I scratch to early (still soft) I will pull the bonding of the wall and if I leave it to late then I wont be able. When do I sctratch?

A quick reply would be great as bonding setting as I type.

 

[roughcaster]

I know it's far too late now Raydar, as you posted your question yesterday,,, but I would say that if you're going to float and set a wall, with bonding coat/multi finish, it's much better to do the whole job in one go,,,,, float/coat in the morning,,, let it set up,, then set/finish onto it, soon afterwards........
Knowing when to devil/scratch the float coat??? Put the coat on, screed/level it off, and leave it a while to steady up,,, keep you're eye on it though, especially if it's onto bricks or blocks, (suction),,,,, then try the float over it. As you get more experienced, you'll know when it's time. I would say though,, for you, if a little unsure,,, when you see the bonding beginning to get "small" dark patches in, (later in it's life), scratch it,,, or, if you feel confident enough, try it a little earlier. You dont need to scratch it too much or too deep either,,,, a "figure of eight" or a "circular"movement with the float over the area, will provide a good enough key..... If you're capable enough to coat a wall and screed it off, then I see no problem for you scratching it,,, ,,,,,, but to float a wall one day and finish it the next, can/will be a nightmare for the inexperienced......

Just to make this clear,,, it's a different story if the scratched float coat is sand and cement/render based,,, you "would" leave that until the following day,, at least,, before you put any finish on.



Roughcaster.