Sandpaper: Here’s the nitty-gritty

Question: What is meant by the phrase “grade of abrasive paper,” and what does “raising the grain” mean?

Answer: The “grade” (or grit) of abrasive paper refers to the size of the abrasive particles in the sandpaper. Given the same number of passes and the same amount of pressure, paper with larger particles sands deeper and rougher than paper containing smaller particles. A lower number indicates that the grade of the paper is used for rough sanding, and a high number indicates the sandpaper is meant for finish sanding.

Generally speaking, 30- and 60-grit papers are used for rough sanding, 100- to 150-grit sandpaper is for medium sanding and 220-grit sandpaper is used for finish sanding. But this changes depending on the type of wood and whether the sanding is done by hand or with a machine.

The best way to determine what grit to use is to test-sand. Start with the finer grits (150 to 220) and slowly work up to the rougher grades.

Sanding a soft wood with rough sandpaper, or sanding perpendicular to the wood fibers, could tear the wood fibers -- causing the grain to rise to the surface. Another way of causing the grain to rise is to over-wet wood; it’s what painters must contend with after the first coat of paint is applied. At this point, and once the paint or varnish has dried, the first coat and the raised surface must be smoothed.

The second coat of finish usually will not raise the grain because the wood is protected from absorbing moisture by the previous coat.

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Hot tubs are not the same as spas

Question: We want to put in a spa or a hot tub. I thought that they were one and the same until we began to shop. What’s the difference?

Answer: Hot tubs are wooden, and spas are fiberglass shells covered with acrylic or other plastic materials. However, some hot tubs have acrylic liners and some spas are free-standing with wood skirts.

Tubs have a rustic and natural appearance; they blend well with decks, gardens and patios.

Spas present more design options than hot tubs and are available in a broad range of colors. Their hard, smooth surfaces make them easier to clean. Support equipment and installations are similar. In either case, most building departments will require a permit for installation. And be prepared for additional expenses.

Make sure your electrical system can handle the load. You will need at least one additional 110-volt electrical circuit (maybe 220 volt). Your electrical bill can easily jump by $50 per month or more.

Also, some communities require a fence around the area, and most will require a lock on all gates.

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For home improvement tips, go to www.onthehouse.com.