STEP ASIDE Ben Franklin, you're not the only Pennsylvania inventor to hit the big time. At one time Louis Maslow of Wilkes-Barre, Pa., had more than 50 patents under his belt.He's been dead now for seven years, but during his time he invented such items (and the machinery with which to make them) as the caster wheel, a wire dishrack for dishwashers, a wire whip for cooking and the Erecta Shelf.

He was president of his own food-equipment company, Metropolitan Wire Corporation (which celebrates it 50th birthday this year), and a continuous "tinkerer." One of his simpler, but clever, inventions is the Erecta Shelf -- a shelf composed of a series of horizontal chrome-plated bars with three vertical cross bars, to which you can attach additional shelves.

"he originally designed the shelf for restaurants and catering services," says his son, Richard Maslow, now president of the firm. "Before Erecta was around, all industrial shelving was made of sheet metal. My father saw that a better shelf for food could be made of wire -- it's more sanitary since no dust collects and the space between the wires provides better air circulation, very important in food storage.

"I'm sure he never expected to see the shelves used in the home as they are today. The trend of selling commercial equipment for the home market has really skyrocketed."

Saleswoman Janet Gerber of Jarvis Kitchenware, 1990 K St., agrees. "The interest in 'high tech' has made the shelves extremely popular with homeowners."

In "High Tech: The Industrial Style and Source Book for the Home," Joan Kron and Suzanne Slesin devote one section to Maslow's "Metro System," in which they describe some of the newer uses for the wire shelves in and out of the kitchen: for recipe books and over-the-counter shelves, wall systems, wine racks, planters, coffee tables, rolling carts, closet storage shelves -- even a canopy bed.

According to the book, published in 1978, "Metro sells $30 million worth of its Erecta and Super Erecta shelving and accessories per year." Business must be booming because Maslow says that in 1979 Metro Wire's total sales were $50 million.

The Erecta and a newer, fancier version, the Super Erecta Shelf, require no nuts and bolts. The Erecta Shelf has more of an industrial look, (for which it was originally intended) than does the Super Erecta. It's also less less expensive. It comes in only a chrome color, though its imitators usually come in brown and white as well.

To build an upright Erecta shelf unit, start by buying two uprights for the sides at whatever height you need. Buy the number of shelves you want. The shelves lock into the uprights at five-inch intervals.

To assemble the Super Erectra, buy four poles and the number of shelves you need -- each shelf comes with four plastic split sleeves. The sleeves snap together around each post. The tapered opening in the shelf corners slide over the tapered sleeves strengthening the clasp. The Super Erecta shelves also contain a ridged bar that runs on the underside of each shelf, from which utensils can be hung. Judging by area prices, the price for a four shelf Erecta unit starts at $94, while Super Erecta starts at $135.

Since the success of Maslow's Erecta Shelf (Metro Wire claims to control about 75 percent of the market) a number of companies have marketed similar products, including William Hodge and Co. of Philadelphia with their "Postmaster System." Woodward & Lothrop uses the Hodge's four-shelf etagere units to display their kitchenware -- unfortunately these are not for sale.

In addition to not being dust collectors, says Jarvis' Gerber, "the shelves make good use of cubic space. The complaint we hear most often is that the homeowner's kitchen is too small. By suspending pots and pans from a wire shelf, they can make better use of even the tiniest kitchen."

Wire shelving can also help Washingtonians fight Enemy No. 1, the cockroach. Says Frank A. Ludwig of Peter J. Wilson & Associates in Rockville (a Metro Wire distributor), "Because the shelves allow light to penetrate and because the chrome-plated bars are so narrow, there's really no place for a roach to hide."

Another nice feature about wire shelving is that you can add onto it now or years from now. And in a community as transient as Washington, the shelves provide a built-in look that can be easily dismantled for that move overseas.

And if what you're after is more chopping space, some area stores will sell you a butcher-block shelf to go with your unit. At Jarvis Kitchenware, a multipurpose unit is on display, featuring an eight-foot-high unit with only two shelves -- one a chopping board located midway down the unit and one beneath for storage.

Several area stores also carry wire grids that can be hung flush against the wall. The hanging kitchen utensils provide a pretty kitchen design, are easy to reach and save space. Kitchen Bazaar charges $17 for a 15-by-30-inch plastic coated wire grid, made by Copco (includes four hooks and screw-in wall plugs). Kitchen Bazaar carries a wall grid (12-by-30 inches), made by Art Wire, which include two shelves and a dozen hooks -- all for $22.95. The grid alone, which comes in red, yellow, green, chocolate and white, costs $10.

At Jarvis, the grids come in four sizes: the smallest, 12-by-51 inches, costs $22; the largest, at 18-by-60 inches, is $28.

Woodward and Lothrop's carries a grid called "Wall All" by Copco. The grid includes five wire baskets in two sizes, and costs $99.99. Woodies also sells "Grid Works" by Heller. These plastic coated wire grids come in three sizes: 12-by-24 inches for $8; 18-by-24 inches for $10; and 36-by-24 inches for $13.

The Design Store also sells a Copco grid (16-by-30 inches) for $13.95.

The China Closet in Chevy Chase carries the grid systems made by Heller. Their prices are slightly cheaper than Woodies starting at $7.19 for the smallest size. Like Woodies, all sizes come in white, black, yellow, red or green.

Some of the local spots we found to buy wire shelving and accessories:

Jarvis Kitchenware, 1990 K St. NW, carries probably the largest selection of Erecta Shelving in the area, as well as the many accessories that go with it -- ranging from collapsible hook-on baskets to shelf dividers and wine racks.

A single Erecta Shelf (36-by-18-by-13 inches) that screws onto the wall is $29.80; a two-tier shelf (36-by-18-by-22 inches) is $57.40. An upright (89-by-30-by-12 inches) Erecta Shelf unit, with five shelves is $107.00. A coffee table (14 1/2-by-48-by-24 inches) costs $59.20. A Super Erecta etagere with four shelves is $137.60. Wheels are $12 to $15 each, depending whether they're braking casters or not. Shelves ordered at Jarvis can be delivered to store or to customer.

Kitchen Bazaar, 4455 Connecticut Ave. NW, also carries Erecta Shelving. By the piece: a 12-by-48-inch shelf is $19.80, each 63 1/2-inch upright (post) is $16.50. So a four-shelf unit in this size costs $145.20.

In addition to Erecta, Kitchen Bazaar has a number of wire products by the Copco Co. They include the aforementioned wall grid at $17, a hook-on spice rack (3-by-3-by-15 inches) for $11, a hook-on utensil rack for $16, a hook-on bin (large basket) for $20, and a bookshelf and paper-towel rack for $15. All of the Copco products come in chrome or white.

Rovel Co.'s slide-in wire basket/-drawer is carried by Kitchen Bazaar. The top rims slide onto a shelf and the basket hangs below -- $7.

Conran's, off lower Wisconsin Avenue in Georgetown, seems to have adopted the wire-grid motif as its decor theme. Everywhere you look, from the fabric on the tables to the wall coverings -- even the floors -- you see the grid design. In the Erecta line, Conran's charges $24.95 per 18-by-26-inch shelf and $25.95 per 73 1/2-inch upright. Assembled, the four-shelf unit goes for $151.70.

Conran's selection, like the Kitchen Bazaar's, is not limited to Erecta Shelves. They carry British Beylerian products, including red or white wire shelves that screw into the wall ($12.50); Closet Maid's vinyl-coated steel-rod storage rack ($12.95); Wire-ware's spice rack ($17); Shelf-Tech's "Add-On System," which is wire shelving that comes in three sizes, ranging from 2- to 4-feet long ($10 to $15 each), in chocolate or white.

E.B. Adams, 1612 U St. NW, which sells kitchen supplies primarily to restaurants, hotels and the embassies, carries both Erecta and Super Erecta shelves. They will sell Hodge's Postmaster shelves by special order. For the Super Erecta, E.B. Adams charges $6.95 for a 54-inch upright post and $16.70 for a 18-by-24-inch shelf. For Hodge's shelves, a 54-inch upright is $5.14; a 18-by-24-inch shelf is $17.80. E.B. Adams will sell the shelving to homeowners either directly from the factory (the least expensive) or from the store.

Woodward & Lothrop, F Street NW, has a limited selection, but does carry one-style of Hodge's Postmaster shelves. The four-shelf chrome unit includes one butcher-block shelf and a hanging shelf. Cost: $299.99. Woodies also sells a high-tech-looking room divider made of three chrome grid panels, each about 3-by-6 feet; cost: $149.99. In addition, Woodies carries Carefree Living camel-colored wire shelf units. They come in two sizes and can be used separately or combined ($19 for the 29-by-13-by-12-inc h unit, $29.99 for the 30-by-22-by-18-inch unit); Copco's five-jar, hook-on utensil rack ($14) to go with their "Wall-All" (see above); Beylerian's plastic 12 1/2-by-16 1/2-inch grid for $10 in a variety of colors.

Hecht's new Living Quarters Dept. at the F Street NW store sells Wireware's single and double shelves ($11.99 and $19.99) as well as their single and double spice rack ($9.99 and $14.50) and their paper-towel rack and shelf ($14.50). Colors: red, white, yellow and chrome.

The Design Store, 1258 Wisconsin Ave., NW., carries Metrowire's Erecta shelving -- a six-foot high unit with five shelves costs $179. They also sell two sizes of Hodges wall shelves: the single shelf is $17.55; the double shelf, $29.95. In addition they carry the Wireware line of shelves and spice racks.