Cutting Fiber-CementContinued

The Makita 5057KB 110-volt 7 1/4-inch saw with dust collector is excellent for production fiber-cement siding work ($329 retail, replacement blade is $33 retail). It's solidly built and lightweight, and cuts any type or size of fiber-cement material available. If you had to choose just one tool, this would be the one. It will make very smooth cuts through five pieces of siding at once (Figure 6). With a cement-cutting diamond-tipped blade, it cuts smoothly and leaves the stock virtually flawless.

Figure 6. If you had to choose just one tool, the Makita 5057KB 110VAC, 7 1/4 inch circular saw with dust collector (left) would be the one. The Makita 5044KB 4-inch circular saw with dust collector (right) is a compact saw that's as solid as the larger Makita, and will cut two pieces at once quite effectively.

Another option from Makita is the 4-inch 5044KB with dust collector. This practical little saw is compact and great for tight spots. It won't cut as many pieces at a time as the larger model, but it's much more portable. I've used this one 25 feet up on a scaffold with no problem ($289 retail, replacement blade is $25 retail). The Makita 5036DWA 18-volt, 61/4-inch cordless is an excellent tool for portability or where electric power is not available (Figure 7). It's not completely dust-free, but the collector does cut down on most of the dust. Teamed up with the 24-inch manual shears, this saw will get you through the job, but I would not recommend it for large jobs. It's especially good for small, quick repairs ($379 retail, replacement blade is $26 retail).

Figure 7. The Makita 5036DWA 18-volt cordless fiber-cement saw with dust collector. (PHOTO: MAKITA)

Blades. I tried blades made by American Tool, DeWalt, Hitachi, Magna, and the stock Makita blades that came with the saw. The blades all worked about the same, which was very well. I've been using some of these blades for almost eight months and they are not even close to worn out. Typically, these blades have either four or six teeth. Those with more teeth cut smoother, but the blades with fewer teeth definitely last longer (see "").

What to Buy

I'd advise anyone who installs cement siding with any frequency to invest in at least one set of nippers and one good dust-collecting circular saw with cement-cutting diamond-tip blades. For larger or commercial projects, a 14-inch pneumatic shear is a good investment. For the contractor who only occasionally works with cement siding, or for the one-time installation, it's possible to get by with the old reliable circular saw using a diamond-tipped fiber-cement blade. Rodney Proctor is a general contractor from Cedar Park, Tex.

Fiber-Cement Blades There are several new blades designed specifically for fiber-cement. Although regular carbide blades will cut fiber-cement, they won't last long and they will make a mess. The dedicated blades are definitely an improvement: They last much longer (we don't know how much longer yet, but manufacturers' claims vary from 100 to 225 times as long as regular carbide blades), and they produce a lot less dust. American Tool Fibercut Blade. Available with four diamond teeth ($90-$100) for cutting stacks of material and a 6-tooth model with carbide teeth ($20) for cutting single sheets; American Tool, 92 Grant St., Wilmington, OH 45177; 800/866-5740; www.americantool.com. (PHOTO: AMERICAN TOOL) Hitachi Fiber-Cement Saw Blade. Developed in co-operation withJames Hardie Building Products, this 4-tooth blade uses polycrystalline diamond (PCD) tips. A layer of powdered diamond is bonded to the tungsten-carbide tips through microwave heating, $69; Hitachi Power Tools, 3950 Steve Reynolds Blvd., Norcross, GA 30093; 800/546-1666; www.hitachi.com/powertools. DeWalt Fiber-Cement Saw Blade. Six-tooth polycrystalline diamond blade with a 5-degree negative hook angle for a better finish on the cut. Suitable for single or stacked cuts, $59; DeWalt, P.O. Box 158, Hampstead, MD 21074; 800/433-9258; www.dewalt.com. Magna M87340 Fiber-Cement Blade. Four-tooth chemical-vapor deposition blade, with 10-degree positive hook angle for ease of cutting and longer blade life. From $65 to $71; Magna Industrial Tool , 101 S. 5th St., Louisville, KY 40202; 800/624-9044; www.magnatool.com.