Failed 5:1 Mist coat

[cortina]

Having applied a mist coat of 5:1 matt emulsion:water to newly plastered walls (done 8 months ago) I decided to test whether it had stuck prior to a light sand. Using sellotape there were some areas where the entire mist coat came off and others where it was firmly stuck. Is this a true failure to adhere to the plaster and if so is the best measure to re-mist with a diluter mix?

 

[Brutal]

I think you'll find if you stick sellotape onto any mis coated walls in parts it will come off!

 

[Zampa]

It cuols be down to so many factors..method of applying, the plaster itself having a slurry over it, the brand of paint, whether the plaster had been polished up first.

 

[confidentincompetent]

My version of a 'mist coat mix' is 5 paint and 2 water @least.. sometimes 1/2 x1/2 depending on how 'hot' the plaster is. Wonder if your mix was too thick.

 

[spice]

My version of a 'mist coat mix' is 5 paint and 2 water @least.. sometimes 1/2 x1/2 depending on how 'hot' the plaster is. Wonder if your mix was too thick.

Hmmm, my thoughts too, 5-1 is far too thick for a miscoat, and why would want to put cellotape on the new paint anyway

When I have hung Xmas decorations on the walls, on existing paint thats been there for a good year - 18 months it has taken the paint off, so I would never use cellotape again.

 

[joe-90]

A ratio of 5:1 is the same as diluting 20% - which is what most manufacturers recommend.

 

[Zampa]

Yeh I picked up on that too Joe..personally I think its way off though

Those of you who remember brolac superflat...you could go 50/50 with that and it was fine...super matt is about the same.

Dont be hard on yourself Cortina...you probably didnt do anything wrong...but as the other said stick selotape on it and pulling it off would do that anyway.

 

[cortina]

Thankyou for all the replies.

Mist coat definately less well stuck at shoulder height where plaster more polished compared to corners of wall etc. Think this and only a 20% dilute mist coat contributed.

Sellotape really just an idea to see if you could tell how strongly stuck the mist coat was before next couple of coats go on. With xmas decs going up in the next few weeks will use nails!

 

[spice]

Noooo, dont use nails cortina lol, use bluetak, and if you have trouble getting the bluetack off, then dab it with a bit of white spirit, no tear marks, no peeling of paint either.

 

[Growler]

cortina:

You're probably better off using plaster sealer in the future.

Mist coats aren't for you.