Paint cracking on caulk

[cocoots100]

Hi there

After I line a room I always run a bead of caulk where the paper meets the skirtings, door frame and especially in the corners.
I use this dow corning product from Brewers http://www.geocel.co.uk/product.aspx?id=137&pt=adhesives which is an acrylic filler. The problem arises when I then paint over the caulked areas, when the paint has cured it almost always cracks (tiny hairline cracks over the caulk where the paint is unable to adhere to the caulk). The paints are dulux trade vinyl matt's (slightly thinned by about 10%). I have changed the brand of caulk (to polycell) but still get the same issues. Just wondering if anyone has experienced the same problems and is there a workaround to avoid this happening again?
Cheers
Tony

 

[spice]

You should really wait till the paper is fully dry before you caulk it, its best the next day.
Even though some caulk says 'overpaint in an hour', I never do, I leave it for as long as possible.

One way to get round this to avoid the cracking/crazing on the caulk, it to caulk as normal, wait a couple of hours, then go over it with oilbased undercoat.
leave to dry, then paint as normal.

 

[Zampa]

You might be putting the caulk on too thick...as it dries it shrinks but the paint doesnt shrink with it..

You really only want thinnest of beads of caulk if your going to do it like that

 

[cocoots100]

thanks for the replies. I guess I do get over zealous with the caulk at times. When these cracks appear, is it just a case of a light rub down and apply further coats until the cracks are no longer?

 

[confidentincompetent]

thanks for the replies. I guess I do get over zealous with the caulk at times. When these cracks appear, is it just a case of a light rub down and apply further coats until the cracks are no longer?

I do the same as spice .... use oil based u/c.. Think it's like 'Mud Cracking' and if you carry on with waterbased it will just crack more...Happens mostly with MATT.. but notice it dont so much with silk/soft sheen emulsions, q/d eggshell or satinwood.