In article ,
mikesmith writes:

With deep holes to fill do people fill with several applications and
let the previous one dry out totally - or one "big" overfill and sand
down when thoroughly dry.

I tend to use one big underfill to within a 1-2mm of the surface
which may well crack as it sets but that doesn't matter, and then
a thin coat polished off with a wet trowel or scraper to match
the surrounding surface. No sanding required.

Also - I have a box I have had for at least three years - does it go
off (in the past its use by date sense) - I have noticed hairline
cracks in some of the filling I have done.

I tend to use plaster rather than polyfilla. I always use plaster
which has gone well past it's use-by date for filling, because it
sets quickly. I do recall using what must have been very old
polyfilla in the past, and don't recall any resulting issues.

--
Andrew Gabriel
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