Whichever paint and varnish remover you choose, the techniques employed in using it are fundamentally the same. The basic steps are simple: After preparing the furniture, apply the remover, let it work, and then take off both remover and old finish.
Preparing the Furniture
Before you start to apply paint and varnish remover, remove all hardware from the piece of furniture -- knobs, handles, hinges, decorative locks, escutcheons, and so forth. Make a sketch of the furniture, and key the hardware to it so you'll be able to replace it correctly. If the piece of furniture has doors or drawers, remove them and work on them separately if you can -- but don't force anything; if a part sticks, leave it alone.
If the hardware is clean, set it aside. Otherwise, polish it as appropriate. If it's blemished with paint or finish, drop it into a shallow plastic pan or bucket filled with paint remover, and let it soak while you work on the furniture. A couple of hours in the solution won't hurt it. Store hardware together in a zip-close bag.
Some pieces of furniture may have gilded edges, special finishes in fluting, insets, and so on that you can't remove. If the special finish on your furniture will stand up to it, you can protect these areas with painter's tape. Make sure the edges are pressed firmly against the wood so the remover can't seep under them.
Some finishes can be damaged by the adhesive on tape. For instance, the tape can pull off delicate gilding. If the finish is too delicate for masking tape, simply stay a couple of inches away from the area when you apply the remover. For further protection, tear a strip of cloth and apply the strip to the area with a tape-like bandage to help protect the finish. Regardless of how careful you are, finishing residue always seems to find its way onto the parts you want to protect. The cloth will provide a little added insurance.
If the piece of furniture is upholstered, it probably needs new upholstery. Remove the old fabric before you refinish, and make any necessary webbing or support repairs. Replace the upholstery after refinishing. If you want to keep the old upholstery, it's best to remove the fabric before you work on the finish -- but only if you're sure you can put it back on again. If the piece is large, have a professional upholsterer remove and replace the fabric.
There are two unbreakable rules for using paint and varnish remover: Use plenty of remover, and give it plenty of time to work. Don't skimp on materials or on time.
Applying paint remover is a slow, sloppy, smelly job, so it's important to protect your workshop. Cover your worktable and the floor around it with a thick layer of kraft paper or with a plastic dropcloth. Be careful with dropcloths, though, because the plastic is slick. Make sure you have plenty of ventilation, keep the remover away from any open flame, and cover up your skin to prevent irritation.
All removers -- paste or liquid, wash-away or scrape-away -- are applied in the same manner. Considering the quick evaporation of chemicals, it's best to work in small sections, say 3X3-foot areas. It's always easiest to work on a flat surface to keep the remover from dripping off. You may want to turn the furniture piece from time to time while you work.
Apply the paint remover with a wide brush, or just pour it on and distribute it with a brush. The quality or condition of the brush doesn't matter. Lay the remover onto the surface with the flat of the brush, and don't spread out the mixture as you would paint. Use what you think is plenty, and then add some more, coating the surface thickly with the remover.
Use the brush only to distribute the remover; brushing causes the remover to lose a lot of its removal power. The chemicals evaporate very quickly; they evaporate even more rapidly when you brush the solution.
After applying a thick coating of remover, cover the surface with aluminum foil to help slow evaporation. Aluminum foil is especially important for removers that don't contain wax, although it helps slow the evaporation of waxed removers, too. If you're applying remover to a vertical surface that can't be laid flat, use a semi-paste remover and try to cover it with the foil.
Wait about 30 minutes or so before testing the results of the remover -- not 5 or 10 or 20 minutes, but 25 to 30 minutes or even more. Experimentation will show you the optimum time, but taking time at the outset will save you time in the long haul.
While you're waiting, apply the remover to another section of the furniture. Don't remove any old finish from areas that won't show when the piece has been restored. Once you start working on these surfaces, you're stuck with finishing them. The obvious areas are work enough; leave table bottoms and the insides of drawers alone.
After 30 minutes, remove the foil and do some testing. The treated area should by now look bubbly and cracked. Rub your rubber-gloved finger into a small part of the bubbly area. If you can easily work your way to the bare wood, the remover -- and the old finish -- are ready to be removed.
If you can't easily reach bare wood, wait another ten minutes and try again. Paint remover stops working, for all practical purposes, after 40 minutes. If you can't easily reach bare wood after this time and if you're using a non-wash-away remover, scrape away all the old finish with a wide-bladed putty knife. If you're using a wash-away, rinse off the old remover and as much finish as you can with water. Apply another thick coat of the remover and wait again. Try the finger test again. If it still doesn't work, scrape or wash off all the old gunk you can and apply more remover. Keep doing this until you've reached the bare wood. Be sure to give the remover time to work.
Once the finish is ready for final removal, the technique you use should depend on what kind of product you have chosen. Learn more about final finish removal in the next section.