attack of the pimples

abertawejack · 5 May 2010

hi guys
Hope you can advise with my problem
I'm a novice to this muck spreading, I've recently scimmed a couple of bedrooms which came out ok.
The recent wall i scimmed had what resembled pimples in patches over the wall. I cannot recall doing anything different from the rooms I finish upstairs without problem...
I have had the multifinish plaster for about a month.. would this be going off?

On another note, when I'm flattening the second coat there always seem tobe a few blemishes left that need filling and sanding later. Where do you think I'm going wrong..having now done a number of rooms and feel by now I should be getting the finish flat flat that just needs painting. I do need to get the next room right as its the living room..

please advise!
thanks in advance

1john · 6 May 2010

the pimples are a mystery to me too but as for getting walls flat flat, you need to keep doing walls im afraid, what i do is let it set and go off completly, and if I think i can do better i will pva it twice and put a really thin coat over it to get out dips i missed, although this only happens on big walls, smaller walls i seem to have to much time on my hands and i am bored waiting for it to set

trowelmonkey1 · 6 May 2010

pimples will be air trapped when laying on, what were you skimming onto? how were the walls trapped?

only way to deal with these is to leave them well alone and let it pull right in before topping it.

regarding blemishes, it's an eye thing really, if you can see them you can fill them when flatting/troweling, if you don't you will see them after it's too late, quite wipe with some one strike filler though will sort it.

abertawejack · 6 May 2010

HI trowelmonkey1
I scimmed onto old plaster, I gave it two coats of pva, one left to dry the other tacky.
The walls I previously finished did not have these pimples / blisters, these were also old plaster walls..
sorry for my ignorance but not sure what you mean wait till it pull right in before toppinf off! is it leave it longer to go off before flattening.
I keep trowelling the pimples but it was no use they remained, I left to dry then had to sand them along with the filler i applied to the blemishes.

must say it is really frustrating, I really want to finish a wall and walk away knowing that when dry will only need paint..

jrplastering · 6 May 2010

little trick for the pimples it always always works a treat for me once you have spread both coats and done your first trowel take a double page from newspaper and with a slightly wet trowel,, preferably your skimming one trowel the sheet over the pimpled area as smoothly and flat as possible it will imediatly draw in the water. next take off the sheet and repeat always makeing sure to smooth out everytime you remove the sheet, once it looks like its getting there one last sheet on the area and trowel over it a few times and leave till your ready to do your last trowel remove the sheet and trowel up the wall, it should only take a maximum of 3 sheets but dnt really matter if you use more. its a gem of a trick and has helped me out many times.
hope it helps pal
JRP

spreadandlay · 6 May 2010

thanks jrplastering, i plaster almost every day and still learning, great tip

abertawejack · 6 May 2010

Cheers JPR
thanks for the tip, I will certainly use this technique if (i mean when) the pimple/blister problem next occurs.
Do you know the reason and what cause this in the first place?

jrplastering · 7 May 2010

it is usually on bonding, if the bondings just bin ruled off and the pores are open if you know what i mean, but really any thing can trap air when plastering if it has grit on the surface as in .......mabey grit in the glue, then you skim and air can get trapped around the grit. or skrim thats bin put on to anything that has to be glued can cause it also if you have spread the first coat hastely sometimes you get air bubbles that have already popped if you dnt catch these early enough or fill these in with fat properly then again, you can trap air. but now you know my magic so it shouldnt be a problem you can say "what pimples......what them?...... watch this....... and thier gone magic"
JRP

trowelmonkey1 · 7 May 2010

interesting trick jr, will give this one a go and see next time i get an attack.

regarding my reply jack, 'pull in' means firm up, troweling the bubbles will get you nowhere mate, all you'll do is move the air pockets around the wall, so let it firm right up, more than you normally would and then 'top it' apply second coat/application, because the first coat is firm now the top coat will cover over any pimples.

jrplastering · 7 May 2010

as i said this trick is a gem, although sometimes if you leave it on for too long the print transfers onto the plaster and only comes off once you paint over it, but doesnt show through the paint.
found that one out wen i did a female pensioners bedroom ceilin and used a sheet that happend to have the page 3 girl side applied to the ceilin once i took it off finished up i stood back and had a look and low and behold there was amanda 18 from coventry who knows an inordinate amount about politics stareing back at me, luckly the woman did not care and saw the funny side to it haha

Nige F · 8 May 2010

Exellent tip

I`ll tell my boy , who`s just starting out S/E - luckily there is a run of work to keep him going - Pretty good spread for a Left- Hander

. We`re keeping everything crossed . I`ll give him a old "telegraph" or "Times " to use . We want to get a quality image

jrplastering · 8 May 2010

im a left hooker my self makes it really handy when you have to work with anouther spread on a large ares start in the same corner and meet in the other never in eachothers way left is the way forward haha

1john · 8 May 2010

Am I weird in as much as I can do it with either hand (skimming that is)??

jrplastering · 9 May 2010

thats not weird so can i its a very helpful thing to be able to do

stevethespreader · 1 Mar 2011

jrplastering said:
little trick for the pimples it always always works a treat for me once you have spread both coats and done your first trowel take a double page from newspaper and with a slightly wet trowel,, preferably your skimming one trowel the sheet over the pimpled area as smoothly and flat as possible it will imediatly draw in the water. next take off the sheet and repeat always makeing sure to smooth out everytime you remove the sheet, once it looks like its getting there one last sheet on the area and trowel over it a few times and leave till your ready to do your last trowel remove the sheet and trowel up the wall, it should only take a maximum of 3 sheets but dnt really matter if you use more. its a gem of a trick and has helped me out many times.
hope it helps pal
JRP

ill post this here rather than the other post which refered me to it jr, looking at your other posts you have got a sponge float use this, give the affected area a rub up with a not to wet sponge float, the bubbles disapear but dont trowel up imediatley give it a couple of minutes b4 hand

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

attack of the pimples

Similar threads