Painting shelves, undercoat or no undercoat?

Question

I have some new shelves that I want to paint. Do I have to undercoat them? The paint I'll be using is Dulux matt vinyl paint. Can I get away with not undercoating them and just giving them a second coat if they need it?

Answer 1

better safe than sorry. Put a thin coating of emulsion on then cover with gloss paint!

Answer 2

Think if you've gone to the expense of getting new shelves I'd undercoat them first,lightly sand them then paint with 2 coats of the dulux. I know it's a right faff on but the results in the end will be far better.

Answer 3

Prime, undercoat, and paint. Use roller or mohair pad to finish. get the best paint you can - Dulux is OK but not the best. In UK professionals use Leyland paint. Increasingly, oil based paints are unavailable for environmental and health reasons. So when using water based paints quality of paint and care in finishing are more important, otherwise you will be left with a right mess. Good luck.

Answer 4

why would a shelf be any different to a door, or skirting ?

You need to primer and undercoat onto a bare surface. It provides a chemical key to hold the paint onto the wood. multiple layers of top coat do not do this.

It'll flake off if you don't use a primer and undercoat.

Perhaps use a combined primer/undercoat if you want to "get away" with something

Answer 5

Depends what the shelves are made of. If they have knots in the wood, you will not only need to undercoat but you will need to shellac the knots first or else they'll come out through the paint. What are the shelves made out of?

Answer 6

Over what period of time did you do all the painting? What was the weather like? What was the undercoat? Did you let the timber dry thoroughly before you painted? Did you stir your undercoat and top coat thoroughly before applying? (You need to shake a can vigorously for a while then still stir it well for several minutes before you can say it has been done properly). Did you give the undercoat time to dry and cure properly before you applied the top coat? Did you read and follow the instructions to the letter? If you were given 3in1, which is waterbased, as your undercoat (it is suitable for priming and undercoating on all surfaces and with acrylic or enamel under or top coats), this shouldn't have happened. If you were given a "goes on pink, dries white" so you can see what you've covered, as with some ceiling whites, and you hadn't mixed or let it dry properly first, this may have caused your problem. It could be the underlying stain has reacted with the undercoat. This could mean the surface wasn't properly dry after cleaning, or you didn't apply enough undercoat. Two undercoats over old stain or dark paint is a minimum requirement. If the original stain was oil-based, and you didn't use 3in1 as the undercoat, then it will have reacted with the acrylic you applied to it. Switch to 3in1 or an oil-based undercoat and top coat. Did you thoroughly clean and dry your brushes between uses? If not, any residual paint, stain or whatever is probably being spread in the new coats. Wiggle and wash your brushes thoroughly, right up to the "hilt", under running water until the water runs completely clear. By all means soak them in water after you think you've got them clean. If the water is still not clear, repeat washing them under running water. Next, squeeze water out of the bristles, then flick-shake as much more of the water out of the brush as you can. Run the bristles over some clean paper or a towel to remove even more moisture, then wrap in a towel or old clothing to protect the bristles and allow them to dry completely in a warm airy location. This might take a day or more, depending on the weather. Alternate using two different brushes if you need to do the job more quickly than the brush-drying time allows. Do your painting early each day so the paint and your brushes can dry more quickly in the warmth of the afternoon and overnight. Read and follow any instructions on your tins of paint/undercoat. If it says let it dry for a minimum of 24 hours before re-applying, dependent on room temperature, humidity or whatever, then this is what you do. Please provide more details about what you did, for how long, in what conditions and with precisely what materials, and we may be able to provide more specific help. In summary, to fix the problem, sand back well again, clean it down with sugar soap, LET IT DRY THOROUGHLY (wait at least several days to let the timber dry out completely), then apply two coats of 3in1 as an undercoat (let it dry thoroughly in between) and then you can do one or two top coats, with proper drying time between each one. Also, you can always go back to Bunnings, take your receipt, products and the bedside table with you, and ask for their advice! They gave you the advice and provided "suitable" materials in the first place, so ask them to earn their pay... Cheers, Robbie, Victoria, Australia

Answer 7

How long do you plan on keeping them? What are the shelves made of (if particle board - YES you need to!)

Probably, it you want it to look nice and last a long time, you should undercoat them.

Answer 8

A painter friend always said "Two coats of undercoat then one top coat ensures paint will not chip"

Answer 9

Since you plan on giving them a second coat.. I don't see where you need a under coat.unless your going to have them outside in the weather for some reason.

Answer 10

i would reccommend putting an undercoat on aswell as the matt finish as it will be harder wearing and will last longer, hope this helps