[issie]

hi please can anyone advise with the following dilemma,
Had major cracks in kitchen ceiling the plasterer suggested filling them in with isopon and sanding down which he did . Reason he used isopon ( i know its mainly used for motors) was the flexibility for expanding and contracting etc , it seemed to go well until I came to painting it which now has its fourth coat of white matt emulsion and I can still see the tracks coming through loud and clear . Tried a clear sealer on it also and to no joy........ so if there is any solution that someone can tell me about I would be most grateful Issie

 

[Gymschu]

I have never heard of Isopon. Usually with cracks we fill with joint compound after applying some fiberglass mesh tape. Then we PRIME the joint compound after applying 2 to 3 coats. A light sanding preceeds the application of primer. In your case you may have to go to your local paint store to see what type of primer is compatible with the Isopon. You may have to sand the paint off of the patched areas and then prime with the appropriate primer and repaint the whole ceiling.

 

[manandvan]

I only uses BM ceiling white. I like the coverage, the cost and the look of it.

 

[ccarlisle]

Not sure if I can help but here this: "Isopon" seems to be a cellulosic crack filler similar to what we have here called 'Polyfilla'. It is neither an epoxy nor a polyester, 2-component system....so it is paintable etc...

Are you seeing two tracks i.e the both sides of the original crack? Is there any way you can feel these two tracks because if so it's a sanding issue.

But it may be a coverage issue; we have here a paint product that we use to cover water-damage stain marks on ceilings and knots in wood; it is shellac-based and seals and covers at the same time. Called "BIN".

It lays down a proper surface for painting over stains etc by sealing the surface; you paint over it.

Now it may also be an absorption issue; if the paint or primer is being absorbed at a different rate than the rest of the ceiling, then you'll see areas that look different.

Since I'm not sure what you have, that's the best I can offer.

 

[jsheridan]

Carlisle, sounds like he's getting shiners from the absorption rates. the same thing happens when you caulk exterior cracks in flat stucco ceilings. I would suggest upping the sheen to an eggshell, if they sell that in the UK, and try to match the sheen of the surrounding area to the "tracks".