How To Paint Doors Without Brush Marks.

How To Paint Doors Without Brush Marks.

Brush marks, whether on oil or water based paints or varnish are caused when the paint did not flow out properly as it was being applied. Reasons for that range from paint too thick, conditions too warm etc causing the coating to dry too quickly or before it flowed out fully.
A good analogy to explain this phenomenon is imagine a boat gliding along on the surface of the water, it leaves a ‘groove’ in the water as it goes along. The ‘groove’ will ‘heal up’ in a minute or so when the water surface settles down again. When painting, the hairs on the brush leave corresponding ‘grooves’ on the paint surface.

Getting Rid Of Brush Marks On Doors

If you have a doors that has brush marks from previous painting jobs, assuming you are ‘handy’, unsightly brush marks can be eliminated and a lovely repaint job done.

To do that you will require an electric sander, a random orbital type is the best for this job, and you will need a selection of different grit sanding discs, 100 Grit for initial sanding, 120 or 140 grit to smooth and 150 or 180 grit to finish. You will also need a dust mask and a pair of clear safety goggles is recommended. You will also need a 2 or 3” brush or a 4” mini roller with a short nap. The mini roller is great for big areas fast.

If at all possible, detach the door and lay it flat on a steady surface. It is easier to sand and paint if the door is laying flat and it is also easier to paint afterwards. If removing the door is too difficult, carry on with sanding the door in situ.

Next, with the roughest sanding discs (100 grit) sand the flat door panels until you have sanded out all of the ugly brush strokes and old paint. (no need to sand the grooves, any roughness in same can be done by hand if need be. Brush marks are usually obvious only on the panels in any event.) Next stage is using the medium sanding discs, sand out roughness caused by the initial sanding.

Finally, using the 150 grit sanding discs, sand the panels to a smooth final finish. Ready for paint.

How To Paint Doors Without Brush Marks

Whether you have the above scenario of sanding out previous brush marks or if you are planning to paint a new, previously unpainted surface, here is how to paint it without brush marks.

Which Paint or Varnish?

You usually have two options, oil based paint which traditionally has been the most common, or in recent times, water based paint, is becoming more common as the paint technology improves.
Varnish for the most part is polyurethane or oil based.

Painting With Water Based Paint.

Water based paints can sometimes be a bit ‘stiff’ and lack flow depending on room temperature etc. This is what can end up as brush marks later.
How to avoid brush marks. Add some Floetrol, an emulsion paint conditioner (made by Owatrol) into your water based primer/undercoat paint and top coat and it will make the emulsion flow out beautifully and with no brush marks. The old way was to add water to loosen the paint but that weakens the paint and its hiding power. Lightly sand between coats with a smooth sponge block.

Usually you only need between 5 & 15% Floetrol added to the paint. Another benefit of the Floetrol is that it boosts the hiding power of weaker colours such as reds and yellows or where you are trying to bridge a wide colour gap. You can expect to save a few coats meaning less work and a quicker finish to the job.

Painting With Oil Based Paint Or Varnish.

If you plan to use an oil based paint or varnish, to avoid brush marks, add some Owatrol Oil into your oil based paint or varnish. The Owatrol makes your paint flow out lovely and smooth and you won’t have any brush marks. Other big benefits of Owatrol Oil are it boosts hiding power, adhesion (resists peeling) and enables the paint or varnish keep its lovely shine many times longer than it otherwise would. A good trick is to add extra Owatrol Oil into your first coat – to the point of being ‘runny’ as that will boost adhesion and ensure no peeling later. Lightly sand between coats with a smooth sponge block. Top professional painter decorators use this secret method to ensure a perfect long lasting job. Incidentally, do not use white spirit in your oil based paint or varnish when you use Owatrol.

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