Do-it-yourselfers find it hard to justify the expense of portable belt sanders, but this versatile tool is commonplace in the woodworker's shop. What they are as well as what they'll do are the subjects here, and there's a handy comparison chart.
Portable belt sanders do several important things well. While they're designed primarily to remove lots of wood quickly and make surfaces flat, you also can flip many models on their back and use them as a bench sander for smoothing small and irregularly shaped pieces, and for sharpening tools.
Compared to your food processor or a Swiss Army knife, a portable belt sander may not sound like the world's most versatile tool. But when you think about it, the need to remove stock or flatten surfaces (or sharpen tools) pops up with depressing regularity during most woodworking projects. Fact is, if you build solid-wood furniture, make glued-up cabinet doors or tabletops, or do much woodworking at all, you'll learn to appreciate a belt sander in a hurry.
How Portable Belt Sanders Work
The business end of a portable belt sander consists of a removable abrasive bel that is looped around- and held in tension between - two rollers. The tool rests on a flat metal plate over which the abrasive travels. A belt-and-gear drive system or an all- gear drive apparatus links the roller assembly to the tool's motor.
Most machines are belt-driven - system connects the sander's motor to a set of reduction gears attached to the tool's rear, or drive, roller.
All-gear portable belt sanders models eliminate the drive belt entirely, and with it, the problems of slipping belts. They can present interesting design problems, however, since the tool's motor must be placed relatively close to the drive roller. One manufacturer, Black & Decker, positions the motor inside the sanding belt on some portable belt sanders models, a smart solution that also keeps the weight of the machine centered and low.
Until the late 1800s, lumber was sold by the pound, so under that system, dry board foot was less expensive than green wood. So obviously something had to be done.
The system of measurement that evolved centers around the board foot, a measurement that covers all the dimensional variables of cabinet- grade lumber - thickness, width, and length.
Today, when you purchase this type of lumber, you buy it by the board foot. Even if the dealer has the boards already priced, he arrived at those prices by first figuring the number of board foot each contained. It's a good practice to double-check the dealer's figures. To do this and also to help you estimate your lumber needs, you should learn how to figure board feet.
A board foot, simply, is equal to 144 cubic inches of wood. Think of it as a piece I inch thick and 12 inches square. Since board footage is always calculated in quarters of an inch thickness, starting at no less than 1 inch (even if you order less than an inch, you'll pay for the i-inch thickness), a 5/4 board 6 inches wide and 72 inches long would be figured like this: 1.25 (thickness) X6 (width) X72 (length)=540. Divide 540 by 144 to determine the number of board feet in the stock. If the board foot length is stated in feet rather than inches, use the same method but divide your total by 12 instead of 144.
Elegant and distinctive, rich in color and figure, and with working properties unequaled, walnut wood is reserved for the woodworker's finest projects. What's behind this exalted position and the matching price?
Walnut Wood - Brief History
Walnut was prized by the Mediterranean civilizations, not for its wood, but for the abundance of nuts the trees produced. During the Roman conquests, it was planted in what is now England, France, and Spain for this reason.
American pioneers used native walnut to make waterwheels and charcoal for gunpowder, and its bark and nut hulls for cloth dyes. Through World War I, airplane manufacturers found walnut wood to their liking for propellers.
While walnut was used to some extent for furniture, gunstocks, and other items prior to the 1600s, it was William and Mary furniture that cast it into the perpetual limelight.
Walnut Wood - Identification
Of the 15 or so species of walnut found from China to the Black Sea, only three enjoy commercial importance in the United States. English Walnut (.Juglans regia), a light- colored, yet beautifully patterned wood, is grown primarily for its nut crop. White walnut wood (Juglans cinerea), commonly called "butternut," though not as strong as other walnut species, has an attractive grain and working characteristics that make it a favorite with wood carvers. Black walnut Juglans nigra), the most recognizable and famous, continues to hold down its place as the world's premier cabinet wood.
All walnut has very white sapwood. Partly to darken the whiter sap- wood to a uniformly dark color, kiln operators who process black walnut steam it prior to kiln- drying. This additional processing also makes the wood easier to stain, and adds to its cost.
Costly also are the veneers made from black walnut's great variety of figures-crotches, swirls, stumpwood, and burls.
Walnut Wood - Working Properties
Once kiln-dried and made into furniture, walnut wood has a very low conrraction and expansion ratio. While it is hard, strong, stiff, resists shock, and doesn't splinter, walnut surprises woodworkers by being quite suitable for steam bending. Walnut wood also works easily with both hand and power tools, and sands and finishes extremely well.
Walnut Wood - Uses in Woodworking
All commercial species of walnut have the desired properties for fine furniture, architectural woodwork, diy woodworking, turning, and carving. Since walnut is highly shock resistant, it remains the traditional choice for gunstocks. And figured walnut veneers are popular in marquetry.
Walnut Wood - Cost and Availability
White walnut (butternut) and black walnut are commonly available through hardwood dealers, though black walnut wood normally comes in narrower and shorter lengths than other domestic lumber. Black walnut wood falls in the high-priced category due to demand, relative scarcity, and processing. At publication time, kiln-dried black walnut wood ranges between $3.50 and $5 per board foot for 4/4 stock (depending upon where you live), while butternut is $1 less per board foot.
Walnut Wood - Source of Supply
The best black walnut comes from Illinois, Indiana, Iowa, Kentucky, Missouri, Ohio, and Tennessee. Butternut grows from Wisconsin and Illinois eastward into the New England states. English walnut wood follows the same range, but the largest groves are in California, where nuts are commercially harvested.
All cabinet-grade lumber begins as a "green" board (hat's been mill-sawed from a freshly felled tree - the moisture content of a green board will be 28 percent or greater, making it unsuitable for diy woodworking, since all wood shrinks, warps, and splits as it dries.
To remove moisture from green boards, most manufacturers air-dry and kiln-dry them. Air drying reduces the moisture content naturally - workers stack the slabs in such a way that air circulates between the separated layers of boards. Air-drying lowers the moisture content level to between 12 and 17 percent. (This is acceptable for outdoor construction, but don't make any interior projects using air- dried material.)
Kiln-drying takes over where air-drying leaves off. Large ovenlike kilns with carefully controlled temperatures reduce the moisture content to between 6 and 9 percent, the ideal range for interior projects.
With few exceptions, such as dense woods like ebony, which usually are air-dried, retail hardwood dealers sell only kiln-dried lumber. It's stored, and sold, indoors under roof where the elements won't affect it.
When you purchase kiln-dried cabinet quality lumber, store it indoors lying flat on dry sticks of scrap or hardboard. Never lay it directly on concrete because it will absorb excessive moisture. If left exposed to the elements outdoors, kiln-dried lumber can become useless for fine cabinetry. In most cases, though, moisture content absorbed will be of the surface type.
Made of plywood, hardboard, and scrap hardwood, and custom-cut to fit your portable belt sander model, the jigs and fixtures to a workshop are the best choices to allow square edge sanding.
Start with a piece of V plywood large enough to fit your sander, allowing space for clamping at the bottom and the sides. Lay your sander on its side on the plywood and trace its profile, then cut along the line drawn.
Next, place the cutout plywood on a piece of V hardboard the same size and mark the cutout outline. Be sure to leave a ledge to support one side of the sander. After cutting the hardboard to fit, glue it to the plywood and allow the jigs and fixtures assembly to dry.
Lay the sander on the jig so that you can measure the sizes of the two clamping blocks - one for the body and one for the handle. Cut and assemble the hardwood clamps using wing nuts on bolts inserted through the base. To aid in sanding short pieces of material, make the stop fence. It attaches to the jig with V dowels.
How to use the Jig for nice jigs and fixtures
For square-edge sanding of plywood or edge-joined pieces, clamp the jig and sander to your workbench top. Make sure that you don't restrict the motor cooling cutouts, and that you don't turn down the sander clamps so tighl they'll distort the hardboard backing. When sanding edges, lay a piece of hardboard or other material under the stock in order to raise it slightly above the bottom edge of the sanding belt.
Short pieces become easier to sand, too, when you clamp the jig so the belt sander rides in its upside-down position. The stop fence keeps the material that's being sanded from running off the belt. Now you can try jigs and fixtures for your own purpose - enjoy!
Long-time woodworkers have learned through experience the importance of choosing their cabinet quality lumber carefully. They know which species perform well in certain situations, which thicknesse are needed for various projects, and dozens of other important things about choosing and using this most intriguing material.
The series of articles "Choosing and buying cabinet quality lumber" started today attempts to share some of that hard won knowledge with you.
The first thing to realize about cabinet quality lumber is that the rules you probably know about ordering dimension lumber (the type you use for carpentry work) don't apply. Sizing, grading, ordering - they're all different.
Also keep in mind that except for a few white pines, such as Sugar and Idaho, redwood, and aromatic cedar, most of the time you'll be working with hardwoods (see Wood for Woodworking section).
Estimating Your Needs
Before you purchase any cabinet quality lumber for a project, draw a cutting diagram, and figure the board footage needed. And, if at all possible, buy from a dealer who will allow you to hand-select your boards.
Hand-selecting gives you two distinct advantages. First, you can choose the grain, color, and texture you'd like to have for your cabinet quality lumber. Second, you'll be able to select your cabinet quality lumber in sizes that accommodate your cutting list and thus reduce waste.
If you cannot choose your own cabinet quality lumber, allow about 20 percent for waste and add it to your needed board footage.