Smoothing external render?

[AndyDavis]

I've rendered the external walls with a (2 coat) sand-cement mix. I'd like to paint it to get a smooth finish. The walls are a bit rough and not completely flat in some places. Do I need to apply a top coat (of what?) to get it flat and smooth it before painting, or would it be better to just sand it down and then paint over it with smooth masonary paint?

There are few cracks here and there, whats the best way to cover/seal them before painting?

 

[legs-akimbo]

Short of starting again you are pretty much stuck with it!
You get the render flat as its applied not as an afterthought.

 

[AndyDavis]

The render is flat in places, just that the surfaces aren't the same level in all places, but when you rub on it with your hands it doesn't feel smooth. I'm told thats how cement render feels and painting it will give a smooth finish, but I would have thought that if the surface is rough to start with it'll probably still feel a bit rough when you finish painting. Or is it really the painting that makes it smooth?

 

[legs-akimbo]

With respect if you are not a plasterer then it is unlikely you will have achieved a quality finish as rendering is an aspect of the plastering trade that is one of the most skilled. It is all about timing and being able to rule off, float and then apply a sponge finish all in the right time scale for that perfect finish. A top class finish can be seen when looking at the rendered area when the sun is shining across rather than directly onto it, this will show up all the imperfections. Painting will still show off all the bad points but will not be so obvious.... you could allways tyrolean