Читать книгу Practical Weekend Projects for Woodworkers - Phillip Gardner - Страница 25

To release the cutter the collet must be pulled out of the central shaft by the collet nut. This means that the collet nut effectively has to be loosened twice. Initial loosening releases the pressure on the lower shoulder of the collet, and the nut may be turned by hand. The collet remains held in the shaft, so the cutter cannot be removed. As the nut is loosened, it begins to get stiff again as it contacts the upper shoulder of the collet. A spanner is now needed: this time the nut will pull the collet from the tapered shaft, and it will then release its grip on the bit.

Get the Speed Right

Make sure that you move the tool at the optimum speed. If you move too slowly, the bit will overheat and there will be burn marks on the workpiece; too fast and the motor will strain and the cutting process will be difficult. With practice, you will soon get a feel for it. When you reach the end of the cut, release the plunge lock and let the cutter rise out of the workpiece. Turn off the motor and, once it has stopped, put the router aside.

Rules of Routing

Routing may look a little complicated, but that isn’t the case as long as you follow these simple rules:

• Protect yourself—use a dust extractor and wear safety glasses, earmuffs, and a dust mask.

• Make sure the workpiece is securely clamped to the bench before you start. Position any clamps so that they will not interfere with the router’s movement.

• Look after the cutters and keep them sharp. Always unplug the router before changing cutters.

• Never tighten the collet nut without a cutter fitted. This can cause serious damage to the collet, and may even break it, so always leave the nut loose.

• Plan your work carefully. Have a “dry run,” with the router switched off, to ensure that no problems arise.

• Use the variable speed function to suit the cutter and feed rate. Large cutters need slower speeds. Always set the cutter to the appropriate full speed before beginning your cut.

• Check all settings, and make sure that everything is tightened before starting work.

• Make several shallow cuts rather than one deep one. Never make a cut deeper than the diameter of the cutter you are using in one pass. For example, to make a groove ⁵/₁₆ in. (8 mm) deep, make two passes each ⅛ in. (3 mm) deep, followed by a ¹/₁₆ in. (2 mm) pass. This puts less strain on the machine.