Popular Woodworking 2007-12 № 166, страница 32

Fixed guards provide a permanent barrier on a part of a machine. Usually fixed guards are used to cover pulleys and belts, cutterheads on a planer and protect the on/off switch from being accidentally activated. These types of guards require little to no maintenance and provide maximum protection.

Adjustable guards provide a barrier that may be adjusted to facilitate a variety of operations. These guards are set by the operator before the cut is made and they maintain that setting throughout the cut. There are a few downsides to adjustable guards in that they don't stop your hands from entering the danger zone and that they can also limit visibility.

Self-adjusting guards provide a barrier that moves according to the size of the stock entering the point of operation. A self-adjusting guard stays in place when the machine is at rest then adjusts for the wood while the cut is being made. These are the types of guards found on most all woodworking tools such as table saws, jointers and power miter boxes. These guards can require frequent maintenance and they can limit visibility.

Remember: An important part of woodshop safety is that you must guarantee safety for two — you and the machine. It is therefore important to understand the choices you have in deciding which guards will work best. There are three options. The first is to use the standard guards that come with the machine without any alteration. However, there are times when those guards can be cumbersome, difficult to work around or just plain in the way.

The second way to safeguard a machine is to purchase one of the great aftermarket guard systems such as the Biesemeyer, Excalibur or the Brett-guard. (I have always used the Biese-meyer table-saw guard with both the splitter and overhead shield, and have been very happy with its effectiveness on my table saws.)

The third way is to make your own guard or shield. Yes it's perfectly legal to make your own safety guard in your shop. Remember: OSHA does not regulate the individual homeowner's shop. With any homemade guard, it must be well engineered, securely fixed

Hooks and protects. The hook at the end of this push stick protects your thumbs from a common injury on the jointer; plus, it changes the vector of the forces applied to the board to give you more control during the cut.

in position and allow safe operation of the equipment. If you have employees using this equipment, then OSHA rules apply and they require that guards be designed and installed by technically competent and qualified persons. OSHA might also require that the manufacturer of the equipment review the proposed guard design to ensure that the guard will adequately protect your employees.

Making Guards

I recommend that guards and shields be made out of the best material you have available. That might include solid wood, such as the spring-type guard and hold-down, or the wooden block to protect the user from the blades after the cut has been made that are shown on page 44. Baltic birch, MDF and particleboard are all good guarding materials except they can restrict your vision. I recommend you drill a few holes to allow a little peek into what's happening at the point of contact.

The last and probably the best material to use whenever possible is Lexan, a polycarbonate plastic made by General Electric. It is said to be 200 times stronger than Plexiglas. It is worked easily by the band saw, table saw and drill press. It is a bit expensive so I recommend that you buy it as scrap or off-fall from your local plastic dealer. Because Lexan is a polycarbonate material, it can be glued together, but I suggest that you ask your plastic dealer which adhesives

he recommends. It's possible to order a two-part adhesive specially formulated for polycarbonates that is made by IPS Corp. The product is a high-strength clear polyurethane glue called Weld-On 55.

Push Sticks and Other Safety Devices

Push sticks are the ultimate sacrificial tool. If you have one that doesn't have at least one nick or cut in it, then you aren't using it enough. They are used on table saws, band saws, jointers, router tables and shapers to push short or narrow lengths of material through the cut. Some push from behind the work, some hold and push from the center of the work, some are very thin, some are made of plastic and some will be forfeited to make a very specific cut. They are always replaceable. Push sticks are valuable tools regardless of their shapes and sizes. However, there are specific ways to use them and some push sticks are better for certain cuts than others.

It is important to understand when to and when not to use a push stick. As long as you have your hands on a board when making a cut, you will always have a great degree of control. As soon as you use a push stick, you lose a great degree of that control. I would always recommend that you choose to use your hands for pushing your work when you have more than a 3" clearance from the guard — you simply have more control.

However if your hands will be within 3" of the guard then a push stick

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