25 - Special Table Saw Issue, страница 31

LUMBERYARD

Specialty Plywoods

Here are three special types of plywood that have been engineered for specific uses.

Medium-Density Overlay_

■ Medium-density overlay (MDO) is a plywood product that's ideal for outdoor projects, see photo. In fact, many of the green road signs you see along Interstate Highways are made of MDO.

MDO is basically a B-grade plywood free of voids with one or both faces covered with a smooth paper overlay. This overlay is impregnated with phenolic resins to make the plywood abrasion and

water resistant (not waterproof).

A sheet of single-faced ³4"-thick MDO (G1S - good one side) can cost anywhere from 25% to 50% as much its AC grade plywood counterpart. Double-faced MDO (G2S) is about $10 more per sheet than single-faced MDO.

Note: Even though MDO is water resistant, it should be primed and painted with an exterior paint (especially the edges).

^Premium Plywoods

■ At first glance, ApplePly (see photo) and Baltic Birch appear like any other plywood. It's not until you look at the edges that you'll notice a difference. These plywoods have roughly twice the number of plies than standard plywood — which makes them extremely stable.

For jigs and fixtures, I prefer Baltic Birch (birch throughout) because it's the least expensive of

Bending Panel

the two. When it comes to furniture and cabinetry, ApplePly (alder inner plies) is a better choice because of the large selection of face veneers and grades. It machines very well and can be routed.

Because Baltic Birch is made in Europe and Russia, it only comes in metric sizes. ApplePly on the other hand is made in the U.S., and is available in standard thicknesses from an Vs" to 1".

■ The first time I saw a sheet of Bending Panel bent into a tight radius I was impressed. It's a flexible plywood product manufactured by the Danville Plywood Corporation (often sold as Curve-A-Board), see photo.

The secret to bending without freaking is the thickness of the plies and the direction they run. The panel shown has a V^'-thick center ply that holds two thicker

plies together—with the grain of the center ply running perpendicular to them.

Although not intended to be used as a structural material, Bending Panel is used decora-tively for curved panels. According to the manufacturer, it's designed to be bent to a radius of 16". And is available in Vfe", V4", and ³/§" thicknesses, with a birch, maple, or pine veneer.

Sources

• Because these are considered specialty plywoods, not all lumberyards are going to have them in stock, but many will special order them for you.

® For your nearest ApplePly dealer call: States Industries at 300-626-1931

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