Finishing plaster going off in the bucket

[johnc86]

I'm plastering my porch at the moment after boarding it out. I bought a speed skim which I got the first coat on with. I put the plaster on the wall with a roller (yes..YouTube ), it did the job. I found it was hard to get the plaster into the corners with this method. I also found the speedskim as a tendency to catch on the next wall when trying to flatten out near corners.

Had a go with a trowel and hawk today and getting the hang of it and happy with the finush. Problem is, I'm so slow that even a small mix ( say 1L of water with finishing plaster added in) is going hard in the bucket before I've used it.
Is it possible to mix up a larger batch and store it in smaller amounts in sealed tubs to use throughout the day?

Cheers

 

[robinbanks]

No; cement/lime/gypsum substances do not go hard because they dry out, they go hard because they cure - it's a crystallisation reaction where the presence of water causes crystals to grow in the material, locking the aggregate together

Clean tools, clean water, clean bucket, in-date plaster, don't mix it to death and keep it cool. Curing is a chemical reaction; contaminants and heat make it go faster

 

[johnc86]

It's been quite warm last couple of days which probably doesn't help. Everything is spotlessly clean, I've bought a couple of brand new flexible buckets for the job specifically.

Thinking about ready mixed stuff. It's such a ball ache mixing it up just for it to go hard and the have to get it all out of the bucket again.

Wish id just tape and jointed it now

 

[johnc86]

I may be mixing it too much... I was told to aim for the consistency of yogurt. So I've been aiming for that

 

[Wayners]

cream of tartar or buy the proper stuff like extra time if you want to slow the setting times.

Go watch on the trowel on YouTube for help

 

[cdbe]

I use extratime, mix enough for one coat on one wall - 20-30 minutes then bin it, clean bucket and tools, mix a bit less for second coat. Slap it on with a trowel, rough as you like, keep trying with the speed skim, just a matter of practice, and get a plaziflex to finish. You'll have plenty of wastage when you first start.

Take no notice of anything a professional plasterer tells you, unless it's to hire a professional plasterer, or that they'll come and do it for you at the weekend! - in my opinion it's the only trade still in common use that requires talent and skill - what you need are cheats and tips from DIYers who get acceptable results without 20 years of practice. Don't be afraid of filling and sanding, think of the personal satisfaction and the money you've saved!

 

[Notch7]

I may be mixing it too much... I was told to aim for the consistency of yogurt. So I've been aiming for that

British gypsum say 11.5 litres per 25kg bag
however plasterers say more like 12.5 litres per 25kg bag

you should spend no more than about 3-4mins mixing, have a look at Kirk

use extra time to give you an additional 30 mins

note: if you are going onto fresh plasterboard, that should be fine, but beware that some backgrounds are high suction and will dry very very fast

also if you lay it on too thin, you might get similar problem

 

[Wayners]

PVA plasterboard will slow it down.

Tbh you got 45 mins to get it on before it starts setting