How best to tackle new plastering that doesn't appear great?

[dave_104]

Hi

When a plastering job (on new boards) has just been done, and the finish doesn't appear great, then what's the best way of dealing with it?

Some comments I read say do NOT do anything until the mist coat is on, others of course differ. I can feel wobby undulations on my finger tips and there's obvious excess in places that need removing, plus of course any scrapes that need filling.

The room is open plan to another room which is finished. Can anyone recommend a good sander make/model I should use with good dust extraction please?

Thanks, Dave
(please don't say get a new plasterer but maybe I need to next time!)

 

[Wayners]

Bodge a orbital sander on a vacuum and hit it.£70 drywall sander is best but you can use something smaller and cheaper.

120 grade disc

 

[Harry Bloomfield]

(please don't say get a new plasterer but maybe I need to next time!)

Get a plasterer who actually know how to plaster.

 

[dave_104]

Bodge a orbital sander on a vacuum and hit it.£70 drywall sander is best but you can use something smaller and cheaper.

120 grade disc

But before mist coating or after? I don't mind hiring a decent sander as there's a lot of plastering.

 

[dave_104]

Get a plasterer who actually know how to plaster.

I certainly will next time! - everyone says their good though..... Last guy I used done a really perfect job, but he died.

 

[Harry Bloomfield]

there's a lot of plastering.

I certainly will next time! - everyone says their good though..... Last guy I used done a really perfect job, but he died.

Should of asked him to do a smaller area first, to check the finish, before asking him to do the rest.

 

[Notadecor8ter]

Why would you sand down after a mist coat? Surely it's not that bad if you are thinking about this.

I find the earlier you correct plaster hairlines and issues like yours the better it is to layer up paint.

 

[cdbe]

I've recently plastered my extension and the finish was absolutely ****e! One of the ceiling areas was over 30m² and I did it in 5 separate hits.

When I say ****e - I can get it on, I can flatten it with a big speedskim and I can go over it with a plaziflex; what I can't seem to do is the last stage where you get rid of the trowel marks and tiny holes/pits.

So I bought a big bag of toupret filler, a Vitrex pole sander and a little Makita orbital disc sander (£50 from Screwfix).

So this is how it works: in theory, to improve the finish you can sand down the high bits and fill the low bits so it all "meets in the middle".

The pole sander is a waste of time, they're designed for soft drywall compound and even with a rough 60 grit disc they barely touch multifinish (now they might be of some use if it's so bad that you're having to cover the majority of the surface with filler as it'll sand that down fine).

The little Makita thing is what you need (but it'll need bodging into your hoover as the outlet is an odd little thing). Start with 60 grit, find a rough bit and have a go. You should find that most of the imperfections just disappear, but the knack is knowing when to stop - you can sand away enough material to fit rid of all the pits but you start dipping the area and loose that flat finish, I generally give it a few passes then leave it.

Next get your filler and fill the imperfections, then resand with an 80 or 120.

With my poor job it was almost neverending, but when I thought I'd got most of it I put on a mist coat. The sanding will have damaged the smooth plaster finish (although depending on how bad the work was you probably didn't have one to start with - especially me as I can't grip that polishing stage) and the wall will literally drink the first mist coat, so put another one on and this will give you an indication of your finish - hopefully it will be looking reasonable. Sand it down with a 120 and check again. At this stage I went over mine with a pencil and highlighted the final areas needing another full and sand. This process you can repeat ad-infinitum till it's perfect or you get bored.

You must mist coat it till the surface is fully sealed.

Then apply your finish coats.

Other people have other methods but this worked for me - I'm fairly picky but now happy with the finish.

I think I was too ashamed to take many before pictures but these are during and after: