Popular Woodworking 2007-11 № 165, страница 50

the wood forces the wood down to the control of the table. The point of operation on a power miter box is at the bed and the fence. Because the wood is held stationary during the cutting process, it makes control easy to manage, unlike a table saw. Another great way to describe control is by examining the cut that takes place on a band saw. As the blade rotates downward toward the table, all the force behind the blade is pushing the wood directly on the table. As long as the wood is flatly supported on the band saw table, at the point of contact, there will be no kicking or grabbing because the control is the table at the point of the cut.

Control can also be added to machines by the guarding, hold-down devices, fences, fingerboards, push sticks and other devices. Machine control and ways to create additional control will be discussed with each individual machine throughout this series. But remember this: No cut should ever be made without the use of the control surfaces.

Limit Your Exposure

I like to give two meanings to the word "exposure." The first is obvious: How much cutter are you presenting at the point of contact? For example: How high should the blade be above the thickness of a board when using a table saw? I've lectured at trade shows for nearly 20 years and still shudder at how irresponsible "pitch men" selling blades and saw accessories can be. No guards, no splitter, blades as high as they go.

Face it, we live in a world where "guards removed for clarity" is an acceptable way to work in the shop. That's just wrong. There is no advantage to seeing the actual cut take place when it causes the user to be at risk. We know what wood looks like when it's cut. When it comes to how much blade should be exposed, the rule is to minimize not maximize. Like the late Roger Cliffe use to say: "How high the blade should be above your work is a definition of terms, the difference between amputation and laceration."

The second type of exposure is in terms of repetitiveness. Each time you make multiple cuts or passes you put yourself at more risk. For example there is no sense in making several passes over

a table saw blade to make a wide cut when you could have done it in one pass with a dado blade. As you expose yourself to extra passes or multiple moves, you expose yourself to more risk. Exposure, however, can cut both ways. I believe it is better to make two passes at Vl6" on a jointer to remove 1/8" of stock rather than to make one pass with an V8" -deep cut. There will be less blade exposed, less kicking force and if the grain tears out on the first pass, it is easy to correct it on the second pass. This second point of exposure merely causes you to think about the safest way to approach each cut on any given machine.

Three Types of Limitations

There are three types of limitations to consider. The first two are common-

sense: your physical limitations and the limitations of your shop space. Everyone has difficulties handling a sheet of plywood, jointing the edge of an 8'-long board or band sawing the corners off a large tabletop. There is nothing wrong with asking for or waiting for help to arrive. Just make sure that you and your helper work together as a team and if necessary do a dry run of the motions along with body and hand positions before the cut is performed.

Always dedicate one person to guide or direct the work while the other obeys commands — it's hard to have two people steer a car at the same time.

The second common-sense limitation is determined by the space in your shop. Small shops will require a lot of pre-planning and strategies for large or heavy wood.

Don't overexpose yourself. It's riskier to take five small cuts with a standard-kerf saw blade when one cut with a dado stack will do the job. Unnecessary repetitive cuts expose you to more danger.

The 3" rule. When a cut will take your hands within 3" of the machine's guard, you should use strategies (such as push sticks) that will keep your stock under control and your hands at least 3" away from the guard.

48 ■ Popular Woodworking November 2007