On 14/05/2019 17:54, Jim K.. wrote:
Andrew Wrote in message:
On 12/05/2019 11:48, wrote:
On Saturday, 11 May 2019 20:43:32 UTC+1, Andrew wrote:
On 09/05/2019 19:34, alan_m wrote:
On 09/05/2019 17:51, TMH wrote:
On 08/05/2019 18:10, Andrew wrote:

Keep a bag of out-of-date Wickes fine surface plaster and use
that. It sets within minutes and unlike gypsum plaster it can
be scraped flat (with a steel ruler) and also sanded.

I'll check that out. Does it have to be out of date?


I presume it's like very out of date gyssum plaster that sets hard
within 5 to 10 minutes of mixing. When renovating my house 30+ years ago
I used some out of date plaster as a grip fix adhesive for installing
electrical back boxes in rather irregular holes in the walls. Being
quick set a few blobs of old plaster would hold the boxes firmly in
position with 5 minutes with enough time to make sure that they were
horizontal and flush with the rest of the wall. Fresh plaster was used
for making good afterwards. I used cheap disposable plastic cups to mix
enough for one back box at a time.


Out-of-date gypsum plaster goes off and sets too hard to allow any
remedial work, short of messay power tools. The Wickes fine surface
filler does allow some 'shaping' with a decent scraper like a steel
ruler after it has set but before dry (unless they have changed the
formulation since I last did so, a few years ago).

Don't fill so badly that you need to remedy it. Why do people do that?


NT


Because the whole point of using some 'old' plaster/fller is because
it will set quite quickly (sometimes a necessity), but on occasions
sets a bit too quickly while trying to get a nice flat smooth
finish.

If time was not an issue then use fresh stuff.


Hang on, you sound like someone who's actually done it? Or are you
another "## merchant" to keep an eye on?
;-)


DIY, I used it a lot a few year back as I decorated each room in turn.
Back in 2009 it came in 5 kg packs, in tough plastic bags, which
is fairly convenient, less wastage.

My 1976 house has very crumbly sand/cement basecoat plaster with a wafer
thin skim of grey gypsum, needing a lot of patching.

Drilling holes would typically result in a hole about an inch across
as the plaster just disintegrated !. I soon noticed that particular type
of filler tended to set fairly quickly once it was 'old' so handy for
fixing these holes or for example, like when changing a single socket to
a double, needing a small amount of filler that set quickly but could
(if necessary) still be mechanically smoothed.