How do you avoid brush marks in water based paint?

[Jan Wysocki]

I've tried using both International water based Radiator Paint and ICI's Dulux "Realife Tough Satin" in brilliant white. Both are reassuringly white and delightfully smell free, but dry before the brush marks have disappeaed.

I have no problem with brush marks in either Gloss or Satin (my preference) paint finishes. I guess that the problem with water based paints is that they dry before surface tension has enough time to force an even surface.

I guess that only painting during rainstorms or when boiling a kettle might help, but I'd be grateful for other suggestions. I realise that a foam roller would probably give a better finish on a flat surface, but radiators and other items I want to paint, are far from flat.

Will I have problems if I rub down the water based paint and recoat it with conventional Satinwood? (I'm thinking of the sort of disasters you get if you try and paint Finnegan's Hammerite over oil based paint:)

[TonyK]

You answer your own question. Use solvent based paints. And no, you shouldn't have any great prob overcoating with solvent based Satinwood. Personally I find the Dulux trade paints better than the shed stuff but that might just be a perception.

HTH

[Paper2002AD]

Try using a mini-roller

[Michael Mcneil]

I can't understand how a waterbased paint will work on a radiator. Shows what I know though.

Brushed paint or any other brushed on application leaves a very thin and uneven layer compared to roller or spray. You could try brushing in a variety of directions. Apply the paint left to right then spread out up and down and follow up with a second coat applied diagonally in one direction then brushing it out again at 90 degrees to the application stroke.

Then sand it down lightly and give it a coat of oil based finish.

[RichardS]

for a large flat surface I'd agree with you (for the best finish, I've found that laying on with a mini gloss roller followed by laying off with a good quality 2" brush works well), but for a radiator I'm not sure there's much advantage.

I'd go for a decent oil-based trade eggshell. They're delightful to paint with.

[chris French]

In message , TonyK writes

Not necessarily, according to the Dulux website their 'Trade' paints are of a slightly different composition - main difference it says is that many pro's like to thin the paint a bit so it is mad with that in mind - whereas the consumer stuff is made with being used straight.

Certainly their trade emulsion seems to take more diluting that the shed stuff - though I only dilute for doing bare plaster.

[TonyK]

Makes sense. I certainly find their trade solvent paints far more workable than shed stuff. Prob. find the VOCs are hihgher and maybe have a longer drying time (16hrs for trade Satinwood)

[Christian McArdle]

Water based paints do hold brush marks more. However, this can be reduced by painting the radiator flat on the ground. Gravity then assists with levelling. I've certainly managed to get entirely flat surfaces using water based acrylics, provided the surface is horizontal.

You may find it flows better diluted 10%. Read the instructions to see if dilution is permitted.

Christian.