by Lb
Hello
Just re skimmed a ceiling had to use bit of bonding on low area first then skimmed over binding was still damp but hard.. When applying second coat the plaster just fell away over small section of bonding and strim.tape can't work it out? May have to re skim to.fix
Answer
I've not come across this problem before - all I can assume is that either the 1st coat was not properly pushed into the bonding coat - in which case lots of firm pressure when applying the plaster. Or it may be that the bonding coat was so smooth - in which case ensure it is roughed up a bit.
If you have enough of a key i.e a really rough surface, then plaster will stick to anything, so that is the sure way to ensure you don't get any more problems - if you've used your float ensure you have some nails protruding through the surface by about 1mm - this will scratch the surface to provide a key. Also ensure that 1st coat is pushed in nice and tight and all should be well.