plaster disaster

[sterling]

determind to master plastering. first wall was not too bad. latest attempts have been not so good.

did a ceiling recently first coat went on great had time to smooth fill holes etc. second coat mixure was leaving holes/bubbles, think maybe the plaster was too thick? when the plaster dried i could see loads of low spots.

having trouble with the corners, seems to spend too much time trying to make them good, looks ok when wet then after ive flicked water on etc. it dryes and doesnt looks smooth with low spots. even worse where ive took my time in the corners.

im using a spare piece of kitchen worktop as my spot board, is this ok. or does this speed up the drying time?

any advice would be great.

[The3rd Earl Of Derby]

I have,but seems theres a new forum.

Refer to the *new plastering forum* thread.

[Phil L]

What for? - this group still deals with plastering does it not/ - or are we to have seperate groups for plaster, plumbing, fencing, falling-downstairs-with-a-bucket-of-paint?

[Phil L]

How long did you leave it between coats? - FWIW, on a ceiling, you don't leave any time between coats, as soon as you've got the whole thing first coated, you start to apply the second, and you don't try to smooth the first coat at all, otherwise it will be as hard as a dogs head before the second coat is applied.

1) Get it all on. 2) see number 1 3) Get second coat on (starting in the same place as you did previously, don't start from where you finished the 1st coat just because your steps/planks are there, and don't apply any skimming that has started to go off - lash it and mix some more) 4) Don't attempt to get it 'anything like' until you have completed 1-3 5) go over it with a *wet* *trowel*, but as you near the 'end', IE the last bit you put on, you may need to splash the plaster a bit if it's started drying...this stage is only to get out the worst of the lines, the final polishing comes later so don't spend too long on each section. 6) when it's all fairly flat and fairly stiffish, go over it again splashing the plaster (don't 'paint' the water on, flick it) and trowel it up to a decent finish....I could give away a trade secret here but I may get shot so I won't. :-p

It doesn't matter what you use as your spotboard so long as it's not absorbent, chipboard etc, worktop is fine if you use the shiny side :-p

[marvelus]

the bubbles are due to working the plaster too early but they usualy flatten out when you are troweling it latter. the low spot problem is probably due to you not putting consistent amounts of plaster on all over the boards and is all down to practise.

I've got a corner trowel which gives you a true 90 degrees, you use it after the plaster has started to go off. A feather edge is also usefull to make sure the corner is in one line (as it were). I work the corners by placing the trowel at an acute angle into the corner then rub it up and down a few times then sweep away. Seems to gives nice results.

no problems with that.

Apparently multi-finish gives you more time before it goes off than board-finish if thats what you've been using.

[sm_jamieson]

I've had plasterers doing work before and they have never put 2 coats of skim over plasterboard - maybe different over wet plaster though. Problem is, the first coat need not be smoothed, but if not sufficiently flat, when applying the seconds coat, you will be trying to scrape the partly set first coat, which will result in disaster ! Simon (who tried plastering and realised I needed *much* more practice)

[Matt]

Washing up liquid?

[Phil L]

No, it doesn't work on skimming and creates more problems than it solves