Mixing plaster

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realtek

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hi,

I know 25kg of multi finish covers about 10sqm.

My wall is 8sqm so given the second coat is thinner how much of a bag to I mix up for the first coat? A bit more than half or 2/3 ?

Cheers!
 
I was going to do that but it's my first time since I did a course. Will be as quick as I can but thought it was better to mix fresh after the first coat? Didn't want it to end up too stiff. I guess if it was then I could just throw it away and mix up a new load :)
 
Just be careful when using the same mix and wetting it back.
If it's started to turn and pull stiff in the bucket before you re wet it and mix use fresh as it will just go lumpy and flash set.
 
Thanks reeves,

Well after a knackering day i cover about 12sqm of the conservatory. I'm pleased with most walls. But unfortunately I did the big wall first 1.8m x 4.2. It turned out ok but was a nightmare to keep up with the drying of the drying times.

Will see when it goes lighter but I can feel a few ridges in it and it's not as good as I hoped or even did on my course.

By the time I got the first coat on the mix started to dry, managed to whack that on but my arm was killing and by the time I finished that and smoothed out some trowel marks, I think I left it a bit too long for the first wet troweling.

Will have a think but may consider re-skimming if not happy and will mix fresh after the first coat next time and from doing the other walls I think I am a bit better at my timings.

Still got a few more bits to plaster too but that's a job for next weekend!
 
Thanks reeves,

Well after a knackering day i cover about 12sqm of the conservatory. I'm pleased with most walls. But unfortunately I did the big wall first 1.8m x 4.2. It turned out ok but was a nightmare to keep up with the drying of the drying times.

Will see when it goes lighter but I can feel a few ridges in it and it's not as good as I hoped or even did on my course.

By the time I got the first coat on the mix started to dry, managed to whack that on but my arm was killing and by the time I finished that and smoothed out some trowel marks, I think I left it a bit too long for the first wet troweling.

Will have a think but may consider re-skimming if not happy and will mix fresh after the first coat next time and from doing the other walls I think I am a bit better at my timings.

Still got a few more bits to plaster too but that's a job for next weekend!
If you re skim it and the current skim has dried make sure you pva the hell out of the wall otherwise you'll struggle even more
As bare plaster acts like a big sponge and takes all the moisture straight out.
I'd be inclined to give it a good 3 coats of pva starting with a strong mix letting it dry and getting weaker
Finally skimming when the last coat is tacky

Alternatively you could give it a couple of coats of Matt paint to seal it then a good coat of pva and skim again when tacky.

Even this time of year conservatories can be tricky for a learner
 
If you re skim it and the current skim has dried make sure you pva the hell out of the wall otherwise you'll struggle even more
As bare plaster acts like a big sponge and takes all the moisture straight out.
I'd be inclined to give it a good 3 coats of pva starting with a strong mix letting it dry and getting weaker
Finally skimming when the last coat is tacky

Alternatively you could give it a couple of coats of Matt paint to seal it then a good coat of pva and skim again when tacky.

Even this time of year conservatories can be tricky for a learner
I have always done the other way round reeves, 2x weak coats to "feed" the surface, and a thicker one before skim to "stick" the skim on.......don't know if it matters as long as it is seals.......just commenting on different procedures.....
 
I have always done the other way round reeves, 2x weak coats to "feed" the surface, and a thicker one before skim to "stick" the skim on.......don't know if it matters as long as it is seals.......just commenting on different procedures.....
I'm sure either way works fine
As you say different strokes different folks.
The main objective the same seal the surface well
I do it that way as the weaker coats dry quicker
 
Do weak first so it soaks in, if you do strong first will just put a film on top off it and not control the suction as well
 
Do weak first so it soaks in, if you do strong first will just put a film on top off it and not control the suction as well
Never had a problem doing it other way
Maybe I was taught wrong. Who knows I've never had a problem with it that way so have never changed or even thought any different. Mind you it was a long time ago now!!

I've seen other people being taught things arse over tit so wouldn't be the first time
 
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