The age of an old house usually can be determined by the number of coats of paint and varnish on doors, molding, woodwork, staircases, windows, kitchen cabinets and mantels.

Everyone along the way wanted to make his or her special decorating statement. If you want to get back to the basic wood or the original finish, you're in for lots of work.

Here's a tip for you: It's easier to strip old finish if the piece you are stripping is lying down.

Some professional paint strippers use a water-lye solution in what is called a 'hot-tank' process. It's bad for wood because it loosens glue in the joints, raises and bleaches the wood, turns oak and mahogany black, destroys vital oils and leaves residue on wood that prevents it from taking paint or varnish.

A much more reliable method is using methylene chloride. You saturate the piece, throw plastic over it and let the chemical sit so that it can do its work. Then you remove the old finish.

I don't do much stripping these days, but when I do, I use semi-paste methylene chloride because the chemical doesn't evaporate as quickly, and cleanup is easier.

Blob it on. Once it is there, don't move it around. Let it do its work.

Some professionals use more than one stripping process. In a hot-dip tank method, sodium hydroxide is used instead of water and lye. Solid-pine doors, with or without hardware, and molding over 12 feet long can be stripped in the tank.

A good professional doesn't just dump the piece in the stripping plant and let it go. "The trick to a good job is keeping an eye on the piece and taking it out at the right moment. Sometimes it raises the grain, but it doesn't matter if you are going to paint."

In the other process, 80 jets spray diluted sodium hydroxide on pieces under eight feet in length. The residue is rinsed off with a pressure washer, Giamboy said.

The price is usually $50 to $70 for a front door, Giamboy said, depending on size. Interior doors cost less.

Glassmire often uses a heat gun to remove all but the final coat of paint. ''But because the heat gun can scorch bare wood, I always use the chemical stripper to remove the final coat."

A heat plate that is used to strip wider areas, such as baseboards, is also available.

To ventilate the area where they are working, Glassmire and Rayser use a two-fan system: one to bring the fumes down to the floor and the other to pull them out an open door or window.

Never use chemical stripper on hot, humid or rainy days, Glassmire said. ''Heat turns the paste to water, and it evaporates quickly. And moisture holds the smell of the chemical, since the air is heavier."

And never use stripper near an open flame, such as a gas heater in a basement, Rayser said. Even a spark from a light switch can ignite fumes.

Before he bids on an on-site job, Glassmire makes a test mark on the work. By doing that, he can determine how many layers of paint are present, the kinds of paint involved, and whether varnish is underneath the paint. Varnish prevents paint from soaking into wood, because paint can become embedded and impossible to remove.

"The trick behind a stripping job is timing. You can't be interrupted. When the paint breaks, you have to be there to take it off," Glassmire said.

Rayser does all the woodwork in a 9-by-12-foot room at one time. He soaks the woodwork along the length of the room first and strips it, then does the width. "This cuts down fumes and the amount of work," he said. Also, remove the shoe molding and strip it separately so the chemical won't ruin the floor.

The first couple of layers of paint usually "break" instantly, Rayser said. How fast the rest loosens is determined by the number of coats and the kind of paint:

"Latex and enamel come off in sheets. Lead-based is like bubble gum. You scrape it, and it sticks to the next spot. You have to get it wet and scrape it off."

Rayser uses Scotch-Brite pads to remove the residue, going with the grain.

For detail work, Glassmire and Rayser make their own tools. Glassmire uses a saber-saw blade to chip off the first hard pieces before using chemical stripper.

Rayser uses a nut pick that he fashions into a kind of spoon and scoops the residue out. He also uses a piece of oak, which won't scratch the grain of the wood, and sharpens it like a toothpick. He also cuts down a brush to make the bristles stiffer and firmly but gently remove the old finish from carvings.

Dental tools should be used when the paint is soft or they'll break, Glassmire said. Cabinetmakers' scrapers also work well.

To dispose of the residue, place it on a piece of plywood in a well ventilated area, Glassmire said. It will dry into a hard substance. Then check with local officials to see how you should get rid of it.

If you gouge the wood, use wood filler, Glassmire said. If it is just a nick, use a wax stick, he added.

When using wood filler, put masking tape around the gouge in the wood. Fill the gouge high because the filler tends to shrink, and give it time to dry. With a fine metal file or an orbital sander, sand the filler to the surface. As you sand, try to break the barrier between the filler and the tape so you blend the gouged area into the wood.

Published: September 23, 2004

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