Q. I've got a pine floor that I'm interested in refinishing, but I'd like to find out the pros and cons of the different types of sealants available: shellac, lacquer, varnish and polyurethanes.
A. "Basically, your choice depends on the type of surface finish you want," says Greg Rewers of Coast Woodworking in El Toro. "Sealants vary in terms of what's called their 'solids content.' Thicker sealants like polyurethane or varnish have more solids, whereas thinner ones like shellac or lacquer have fewer, making them dry a little easier. Polyurethane creates a hard, plastic finish that resists stains, but it takes about 12 to 24 hours for it to dry fully.
"Typically, furniture manufacturers use a lacquer finish because it dries very quickly and leaves a very clean finish. Lacquer will generally dry in as little as 10 minutes. You can spray it on or use a paintbrush and apply several coats, lightly sanding in between each one.
"Shellac dries fast, but it won't give you the same smooth finish as lacquer, and varnish is thick and protective, but it tends to yellow over time and crack."
Q. Our house has been wired with aluminum, and in the course of remodeling, I'd like to connect copper-wired fixtures to the aluminum. Is there any danger in that?
K.A., San Juan Capistrano
A. "First of all, aluminum wiring is not safe whether it's used with copper wiring or not," says Joel Gwartz of B.J. Plumbing & Electrical Supplies in Garden Grove. "Aluminum was used in homes when there were shortages of copper, and aluminum became a cheaper alternative.
"There is a compound called Noalox that's used when joining aluminum to copper. You work it onto the wire with an emery cloth and join the two at a wire nut. There are also switches and outlets you can use to connect copper and aluminum. One of the problems involved is that few manufacturers make the converters necessary for safe connections because aluminum is so unsafe."
Q. I'd like to put new insulation in our attic upstairs. The house is 33 years old, and the insulation, which is blown fiberglass, has become dirty and "flat." Should I remove it before putting in the new insulation?
A. "It's really not all that necessary," says Nancy Kutsch from Wells Insulation in Garden Grove. "It would be a messy job to remove, and there's really no reason to do it. The old insulation is not going to take anything away from the new insulation you put up there."
Q. I have what appears to be an antique oak dresser I bought at a garage sale. However, it's been painted so many times, it's hard to tell if it's even wood. I'd like to strip the paint off and refinish it myself, but is it a job worth doing by myself?
H.I., Fountain Valley
A. "Unfortunately, sometimes pieces of furniture are painted for a reason," says Carolyn Fallon of the Strip Shop in Anaheim. "When wood is painted, its finish is hidden, and there could be a good reason for that. Maybe it's been in a fire or it's had horrible water stains or the previous owners filled in huge gouges with putty.
"If it's been painted by the factory, the finish underneath could be very nice. That's especially true if it's old enough to have been before things like particle board were used.
"You're just going to have to check what went on under the paint to determine whether it is worth refinishing or not. If the paint was applied on a finished surface, it should come up easily. If it was painted on bare wood, you may have a problem getting it off."