Thursday, May 27, 2010

Finally Spring!

After the longest (and coldest) winter North Carolina has seen for years, I’m so glad to say that spring has sprung. The weather has been perfect lately, which has motivated my husband and I to start working on our yard. We’re newlyweds and new homeowners, with a lawn full of dry soil and weeds.

We've been trying to decide what kind of grass to plant for awhile now. We were at Lowe’s the other day, trying to figure out whether to sod or seed (or do a combination of both). Oh the dilemmas I never thought I’d have! Before we bought our house, I didn’t even think twice about grass. Now I’m reading articles like this one and nodding my head in agreement.

While we haven’t yet made a grass-related decision, we were able to agree that our bushes in the front yard were in dire need of some fresh mulch. The old mulch that was around when we bought the house was sun-bleached and completely thinned out. We also bought and spread some pine straw to add some texture. To complete the look, we picked up some new solar landscape lights as well.

Here are the before and after shots: focus on the mulch and please excuse the condition of our grass. We’re hoping to get that under control before we get a notice in the mail from our neighborhood homeowner’s association...




For more information on mulching your yard, check out this article; complete with a handy mulch calculator!


Erinn Honeycutt
Digital Content Specialist

Tuesday, May 25, 2010

Tips For Rust Management

No woodworker who takes pride in his tools wants to see them discolored or damaged by rust, but the battle against this red devil can be a never-ending one. This is especially true for anyone living in oceanfront areas or in regions with big fluctuations in humidity and temperature levels throughout the year.

Short of moving to southern Arizona, most of us have to take preventive measures occasionally to keep rust at bay. For hand tools such as chisels or plane irons, the issue is more a cosmetic one because regular honing or grinding of the cutting edge keeps the business end of the tool in good shape. The idle portion of the blades can be sprayed with lacquer or clear polyurethane, or wiped down with a light machine oil.

The cast iron surfaces of machinery present a bigger challenge because they can’t be wrapped or stored in cases or drawers. They also have much more thermal mass than a small hand tool and so can attract much more moisture condensate. More on this later.

Certain conditions, such as having your shop in a damp basement or an unheated garage, are an invitation to rust. But not all of us have options for relocating our woodworking tools, and in those situations we have to use a mix of strategies:

• If you are uncrating a new machine with cast iron tables, it may have oil-soaked paper stuck to the table, or a brown gelled grease. Use mineral spirits and acetone to dissolve the grease, and wipe repeatedly until no residue is visible. Then either place the machine in sunlight or use a heat lamp to warm up the surface; grease residue will continue to “sweat” from the surface for a short period and it must also be cleaned off with solvents.

• Next, apply a protective layer to the exposed surfaces. Paste wax is a traditional and reasonably effective option, but don’t use automotive waxes containing water or oily additives. These are really for painted surfaces, and they can transfer residue onto workpieces and cause finishing problems later. There are industrial sealants designed specifically for rust prevention on steel and cast iron surfaces. These are designed to seal the surface and dry-cure rather than leave an oil residue the way machine oil or a product like WD-40 might do. Avoid sealers that contain silicone, as they too can leave residues on wood surfaces and interfere with glues and finishes.

• If the cast iron surfaces already have some light rust or oxidation, use fine steel wool, a scrubbing pad, or a rubber abrasive block to remove it. Regular maintenance to remove light rust is critical; if left unchecked, heavy rust will cause a blistering effect on the surface as the large iron oxide molecules displace the smaller iron molecules; if this has already happened, regrinding the table is often the only way to remove the damaged portion of the surface.

• Try to control the shop climate. In basements, run a de-humidifier to remove excess moisture vapor from the air. In garages, try to keep the space heated so the cast iron tables don’t become large thermal sinks that will stay cold for days or weeks after the weather begins to warm up. Spring warming typically brings more humidity, which will condense on the cold machine surfaces and promote rust. If you can’t heat the entire garage effectively, try storing your machines together in one corner and using a small ceiling- or wall-mounted electric infrared heater to keep the tables warmer. Infrared heat warms objects, not the air, so the tables will capture and hold the heat. This is a relatively inexpensive rust-preventive measure and has the added benefit of allowing you to use your shop in colder weather.

• Finally, don’t let moisture sit on the surfaces. This means don’t place a cold drink on your table saw and let it drip condensation onto the cast iron. Also, your own sweat will accelerate rusting in spots, because of the salt content in perspiration. Wipe sweat drops up promptly, and re-apply table sealants on a monthly basis to ensure good protection.

Thursday, May 20, 2010

The Difference Between Hardwoods And Softwoods


Tree species are classified scientifically not according to the kind of lumber they yield but rather by the type of seed they produce.

Softwoods are gymnosperm (literally, naked seed) trees that characteristically have needle-like foliage they retain year round (hence the term “evergreen”). Some species in this group are also known as conifers because they produce seed cones. The seeds are usually lightweight enough to be scattered by the wind after the parent tree releases them. This category includes such species as pine, fir, spruce, hemlock, cedar, and redwood.

Hardwoods are angiosperm (covered seed) trees with flat or broad leaves that typically are shed each autumn and regrow in the spring and summer. These leaf-shedding species are also known as deciduous trees, and they include many familiar lumber varieties—red and white oak, maple, birch, poplar, walnut, and cherry. Their seeds are often enclosed inside a protective shell (think nuts and acorns) or within fruit; they are distributed by falling to the ground or are scattered by animals that use the seeds or their fruit as a food source.

As you might expect, there are a few exceptions to these generalities, and not all woods fall neatly into one category or the other. Boxwood and holly, for example, are small hardwood trees that don’t shed their leaves annually. Balsa, the extremely soft and lightweight wood used widely for craft and modelmaking projects, is technically a hardwood. Conversely, some softwood species such as longleaf heart pine or old-growth Douglas fir are denser and heavier than some hardwoods such as aspen.

In general, these designations are mostly accurate, which is why they have become the popular terminology. Hardwood tree species tend to produce dense and hard lumber, while the lumber from softwood species tends to be less dense and lighter in weight. The scientific classifications, however, are based on seed type and foliage characteristics.

Wednesday, May 12, 2010

Maintaining Saw Blades

With use, all saw blades get dull and dirty and require sharpening and cleaning. Some, such as scroll and band saw blades, can be cleaned, but because they have so many teeth, replacing them is more cost effective than sharpening them. Table and miter saw blades, on the other hand, easily can be cleaned and sharpened, although carbide-tipped blades require less frequent sharpening than high-speed steel blades. Both types will cut truer and last longer if kept clean and stored properly.

Cleaning blades

Saw blades pick up pitch and gum from the wood they cut. If you cut a lot of softwood, the blades can pick up resin as well. Any buildup on your blades will decrease cutting efficiency and sometimes cause burning and ragged cuts. Consider making a blade-cleaning kit that includes a shallow pan large enough for the blade, a toothbrush, rubber gloves, a can of pitch and gum remover, and a cloth. Keep some contractor’s paper or old newspapers on hand, as well, to protect surrounding work surfaces.

To clean a blade, put on rubber gloves, and place the blade in a pan. Spray on one coat of pitch and gum remover, and wait the recommended time. After it has set, scrub the teeth of the blade with a toothbrush to remove stubborn deposits. Use a cloth to wipe off excess residue; then flip the blade and clean the other side. When you’re finished, wipe both sides clean one more time.

Sharpening Carbide-Tipped Blades

It’s best to have this done by a professional who has experience working with carbide. If you don’t know of a local sharpener, consult a local woodworking club or saw-blade manufacturer. Make sure to use a sharpening service recommended by a woodworker.

Sharpening High-Speed Steel Blades

As with any other high-speed steel blade in your workshop, such as a plane or handsaw blade, a high-speed steel saw blade could be sharpened. You should have this done professionally, because if you don’t sharpen every tooth identically and set, or bend, each alternative tooth perfectly, the blade will not run true. The blade can pull to one side if one or more teeth protrude; even worse, these teeth will do all the cutting and dull quickly leaving a jagged cut. Touch-up sharpening can be done by pressing a slim taper file against the tooth so it aligns with the bevel. Then take one or two passes with the file to create a fresh edge.

Proper storage

Finally, you can increase the life of any saw blade by storing it properly. This includes replacing a blade in its original packaging or setting it in a simple storage rack. Both of these methods keep the teeth from coming in contact with metal. When teeth touch, high-speed steel versions will dull, and carbide-tipped blades will fracture or chip.

Wednesday, May 5, 2010

Planning For Shelving Spans

Like most structural or engineering issues related to wood, shelving spans are subject more to general guidelines rather than precise formulas. Why? Because wood originates as a natural living tissue of trees rather than a uniform manufactured material tailored to the whims or needs of woodworkers. Engineered wood products such as plywood are more consistent, but many variables still affect the outcome.

Short of calculating a formula with a slide rule (does anyone remember slide rules?) or a computer, most woodworkers have to “ballpark” their dimensions, and there’s nothing wrong with that. If you want a simple rule-of-thumb that’s easy to remember, think of the common scale used in architectural drawings: ¼ inch equals 1 foot. Borrowed for this purpose, this ratio means a solid hardwood shelf loaded with books can, under the right conditions, span 1 foot of horizontal distance for every ¼ inch of its thickness. For example, a ¾-inch thick oak board typically can span up to 3 feet without significant deflection.

Are there exceptions? Of course, but this guideline provides a reasonable margin of safety. Just keep two key principles in mind: First, wood consists of longitudinal fibers and is strongest in the direction parallel to those fibers (“with the grain”). Second, cutting or breaking those original fiber bonds and reconstituting them with adhesive (such as when producing particleboard) alters and often diminishes the strength of the material.

With these caveats in mind, we can deal with the variables. For instance, dense hardwoods such as oak or maple will support more weight than will a softwood such as pine. Plywood has a cross-grain construction with fibers running in two directions, so its rigidity is compromised slightly. Composites such as particleboard or medium-density fiberboard (MDF) have random fiber orientation, making them more susceptible to bowing and bending.

That said, there are several simple techniques for reinforcing shelves to make them stronger. The most common is to attach a strip of wider solid wood (say 1½-inch) to the front edge of a ¾-inch thick shelf. This creates a rib to stiffen the shelf. If you don’t mind having a lip on both faces, centering the strip on the shelf edge will allow you to flip adjustable shelves over occasionally to compensate for any bowing.

If your bookshelf project has a back panel, as most do, you can drive screws through that panel into the rear edges of the shelves to anchor them at the correct height. This works best on shallow depth shelves (less than 9 inches), because if they are too wide the front edge may sag even while the rear edge is fastened tight. You can also attach metal support brackets to the front face of the back panel and to the underside of the shelf without interfering with the placement of books.