When refinishing old furniture, the preparation of the wood is critical, regardless of whether you are going to paint or revarnish.. Old furniture is mostly finished with varnishes, lacquer and shellac. Most of these are oil based and therefore, present a problem when applying water based paint. The first step I take when painting an older piece of furniture is determining what type of paint is already on the piece. Is it oil-based or is it water-based?
Determining if it’s a water-based or oil product is important.
|Old table refinished in white and yellow|
Oil can be painted over water paint BUT water can’t be painted over oil. If you try to apply acrylic paint over oil paint, the paint will not adhere properly and yellow marks may show through on the surface!
Once you have determined the type of paint, it helps you to decide on the proper paint and primer that you will need for the project.
Here’s a quick and fast way to find out if your piece of furniture is painted in acrylic or oil. This technique will also work on walls, doors, cabinets, baseboards or any other painted surface!
1. Add some rubbing alcohol or nail polish remover to a cotton swab or a clean rag.
2. In a discreet area, wipe the surface back and forth with the rubbing alcohol.
3. If the paint starts to rub off and you see white or faded streaks, you know this has been painted with a water-based product.
4. If no paint comes off, then you know it has been painted with oil based products.
As a general rule the following steps should be followed when painting old furniture:
Step 1 – Clean and sand'
Mix sugar soap with warm water and wash down the work piece. When dry start to remove old finish. Test with 150 grit sand paper to see if the finish can be removed easily. If not, you might have to use a chemical paint stripper to do the job. Where the old finish is still in a good condition, it is not necessary to remove all the finish. Just remove the gloss and then use a finer sand paper such as 220 grit to smooth down the surface. Wipe the wood with a damp cloth to remove the dust.
Step 2 – Fill cracks and holes
Use wood filler to fill holes and cracks. Bigger holes could be filled with wood epoxy to provide a stronger patch. Sand it to a smooth finish. This step might be repeated when the under coat is applied because small scratches and dents will then be more visible.
Step 3 – Seal and prime
When painting with water based paint, it is important to first seal the wood to avoid yellow stains seeping through when you apply the paint. Use water based clear sealer. When dry, sand with a 220 grit sand paper and then apply a multi-purpose undercoat. The work piece should now be ready to apply the first top coat. Remember to sand the undercoat with 220 grit sand paper.
Step 5– Apply top coats (at least 2)
Water based enamel paint is ideal to use as a furniture paint. Some brands are thicker and are non-drip. Whatever the case, the paint should be thinned with water (10%) to make it easier to apply. Do not try and cover the wood in one thick coat. Rather put on 2 or 3 thinner coats and you will get a much smoother finish. Also remember to sand with 220 grit sand paper between coats.
If you are thinking of refinishing old furniture as a home business, you should have a look at "Refinishing Old Furniture - start a home business" .