Popular Woodworking 2007-08 № 163, страница 43

Anti-kickback Pawls

Anti-kickback pawls are placed on both sides of the splitter on U.S. saws as a purported safety feature. The addition of the pawls is an attempt to address wood ejection problems. However, the only time wood can be ejected straight back is when you are cutting narrow strips less than 2" and the strips are not pushed beyond the back of the blade. Otherwise the pawls do not serve their intended purpose and, in fact, are a reason some people remove the entire guard system since the anti-kickback pawls actually get in the way of making narrow cuts.

There are no anti-kickback pawls on European table saws. In eliminating the requirement for anti-kickback pawls, European design reflects that the minor benefit that may accrue from the addition of pawls is not a good tradeoff for the awkwardness of their use.

The new regulations will still require anti-kickback pawls and the regulations will also require that the pawls be able to be removed or reattached in less then 20 seconds without the use of a tool.

Dust Control

There are currently no dust-control regulations for U.S. table saw, and they typically have minimal dust collection. We are now increasingly aware of the health hazards of dust to woodworkers. Classified as a carcinogen , wood dust is responsible for a significant increase in respiratory diseases and nasal cancers as compared to the general population.

U.S.-style cabinet saws, at best, have what I call chip containment and inefficient dust collection . On both cabinet saws and contractor's

Anti-kickback pawls. These toothed, spring-loaded devices are supposed to stop work from flying back at the operator. However, most woodworkers remove them.

saws the maj ority of dust and chips are thrown below the table by the front teeth of the saw blade. There is no efficient way on either type of U.S. saw to direct the dust and chips to a dust collector. Some newer U.S. table saws and most portable table saws do have a better system for collecting sawdust. Like the European table saw, the portion of the blade below the table is shrouded and then ported to an external connection port. The throwing force of the blade directs the sawdust toward the port, which is not only efficient but requires less suction.

European table saws also have a dust port above the table on the blade cover. No U.S .-style saws offer dust collection on the blade guard. Some after-market table saw blade covers offer this option although it does little good unless you have good dust collection below the table first. For effective protection from dust particles, a table saw needs dust ports above and below the saw.

Table Saw Rip Fences

By now you may not be surprised that there are also regulations in Europe that pertain to the rip fence. The regulations say the rip fence must offer two positions and be adjustable in length. There is a high position (50-90mm)

Another sucker. In addition to dust ports in the cabinet, European saws also have a dust port on the blade cover to catch debris flung from the blade.

and a low position (5-15mm). Ifyou have seen a Delta UniFence you have seen a European-style rip fence. The high fence position, the one that U.S. table saws typically use, is for tall or wide work. The low position is for narrow work, allowing room for you to push the work through and still use the blade cover. European table saws have primarily right-tilting blades and the fence in the low position allows the blade to be tilted toward the fence without coming into contact with it. With an adjustable-length fence, the fence can be made shorter, which is especially handy for ripping short pieces.

The Biesemeyer-style fence has become the standard for table saws in the United States. European fences generally seem less rigid when compared to the Biesemeyer-style fence. An extremely rigid fence is advantageous when cutting large panels. However because European table saws have depended more on the sliding table, not the fence, for accuracy when cutting sheet goods and large panels, the rigidity of the fence is not an issue.

Crosscutting

U.S. table saws use a miter gauge for crosscut-ting. The miter gauge is limited in its capacity and accuracy. We have had to resort to shop-made and aftermarket solutions and additional machinery to make up for the shortcomings of the miter gauge. Nearly all professional woodworkers I know who have a U.S. table saw have had to add a crosscut sled for cutting wide and heavy panels. In addition, I have found that aftermarket sliding tables are typically not sufficiently accurate and take up a lot of space. The addition of a miter saw in the woodshop has replaced the less accurate radial arm saw,

Pop the hood. You change the blade by sliding the table back, giving you lots of room to work. At the bottom right of the blade is an adjustable shroud that attaches to the dust-collection system.

52 ■ Popular Woodworking August 2007