Painting Tips -How to Remove Paint and Varnish
Before repainting any surface, surface preparation is a very important step you must not forget. In fact approximately 90% of any repainting is surface preparation. This is because the finish is as good as the surface to which it is bonded. There are 3 ways you can approach this.
You can choose to use
• Chemicals
• Abrasives
• Heat
Let's go through these 3 ways and see how we approach each method.
1. Chemical Removal
Shellac and lacquer finishes are usually easy to remove. To remove shellac, use steel wool and dip it in denatured alcohol. Shellac is thinned with alcohol. In small areas, go over the surface of the wood, moving the steel wool pad in a circular motion. Give the alcohol plenty of time to soften the shellac. To remove lacquer, follow the same procedures as for shellac except use lacquer thinner instead of alcohol
If the thinners do not work adequately, then try paint and varnish remover, applying it with a steel wool pad in a circular motion. Remember to wear gloves as thinners for shellac and lacquer removal can be harmful to your hands.
2. Abrasives
Before we go into the details, here are some rules to follow.
• For the first abrasive cut on thick finishes, use open-coat sandpaper. Once the finish is "thin", switch to a finer, closed-coat paper.
• If the finish is clear, i.e., varnish or shellac or lacquer, use paint remover, alcohol or lacquer thinner.
• If the finish is paint or enamel, you can use abrasives.
Here you can either use an abrasive such as sandpaper, steel wool or pumice to remove paint and lacquer or you can opt to use a paint stripper. If you choose to use sandpaper, use a power sanding tool to quickly and easily remove paint without damaging your hands doing manual sandpaper labour. You must also be careful not to damage the wood while sandpapering. If by power, use only an orbital type or random orbital sander. Do not use disc or belt sanders. Emery paper can be used for metal finishing and it cannot be used for wood finishes.
3. Removing Paint with Heat
Another common device used to remove paint and varnish is a heat gun. You must be extremely careful as the heat can be really hot and scorches easily. Fire or extreme heat can scorch the wood and removing the scorched spot with abrasive or scrapers can be a big problem. Take note that heat tends to work best on painted surfaces, rather than varnish, enamel, shellac, lacquer and so forth.
You can of course use heat for these finishes but the result may not be too effective. When working with heat, always have a bucket of water handy for small fires. Heat is a good finish remover, even if slow. Team a scraper with the heat and run the scraper just as soon as the finish has softened under the heat.
I hope you've understood these 3 ways to remove paint and varnish.