Kamis, 07 April 2016

          Depending on how you look at it, there’s either no difference between a shaper and a router table or a theres great deal of difference. They are the same in that they both work by projecting a cutter or bit up through a hole in the table. The work piece is then run along a fence and through the cutter, producing a profile on the work piece matching that of the cutter.


          In, many other ways, however, they are quite different. The first question you might want to consider is: “Considering the type of woodworking I do (or I am likely to do) in the future, do I need a shaper or will a simple router table do the trick?” What will determine the answer to the question is the size of the profiles you want to create. You do not need to own both a shaper and a router table since many shapers can also spin router bits. However, you cannot spin shaper cutters on a router.


          If you are used to working with routers and router tables, one of the first things you will notice the first time you turn on a shaper is how much quieter it is. The high-pitched whine of the router has been replaced by the quieter whirr that is characteristic of the shaper. The reason for this is two-fold: First, most shapers turn at slower RPMs (7000, to 10,000) than routers which scream along at 20 to 25 thousand RPM. And yet, when you consider the tip speed of the larger shaper cutter as opposed to the router bit, there may not be that much difference in speed at the actual point of cutting. Second, routers are direct drive while shapers use the quieter belt-drive system of rotation.


          Because shaper cutters are so much larger than router bits, they are attached to the shaper differently than router bits are attached to a router. Shapers use heavy metal spindles that are firmly attached into the shaper at the bottom of the spindle. Spindles usually come in 4 sizes: 1/2", 3/4", 1”, and 1 1/4" diameters. Some machines only include one spindle but others supply two or more. There are two types of spindles: “solid” and “interchangeable.” An interchangeable spindle has a hole in the top end which allows you to mount smaller diameter spindles and even router bit collets. An interchangeable spindle can also hold shaper cutters.


          Solid spindles are used only for shaper cutters. Cutters, spacers, rub collars and/or ball bearings are dropped onto the spindle shaft from above and then secured with a large, provided nut. The capacity of a shaper spindle is expressed in available space “under the nut.” The greater the capacity, the more cutters and spacers can be accommodated. Another important figure to look at when shopping for a shaper is the amount of “spindle travel.” This figure relates to how high or low the spindle can be with relationship to the table top. This relates to the maximum thickness of work piece that can be shaped with a profile. Multiple cutters can be put together to create different profiles.


          Generally speaking, the largest shaper cutters work better at lower RPMs. Most shapers will offer you two different speeds. The more expensive shapers may offer you as many as five. Changing speeds is done by moving the drive belt into another pulley position as on a drill press. And, like the drill press, belt tension must be slackened before this can be done. On most shapers, this is accomplished by simply moving a lever that releases the belt tension, then, moving the belt into another pulley position and finally, by moving the lever back to its original “tight” position.


          Most shapers come with grooves for a miter gauge in both the table and the fence. This is to allow small pieces to be shaped safely and effectively. Another piece of equipment relating to safety is the “starter pin”. This is a metal pin, threaded on one end that screws into a threaded hole in the table near the location of the cutter. It gives you a place to rest the work piece against when beginning a freehand cut.


          In a router table, there are two types of router bits you may use: (1) with or (2) without a ball bearing guide. If there is no ball bearing guide on the router bit, you MUST use the router table fence. Same with the shaper. The shaper may use a “rub collar” or a ball bearing on the spindle shaft to prevent the work piece from being drawn into the cutter deeper than the profile. If you are using a cutter without a rub collar or ball bearing, then you will need to use the fence that is installed on the table. The infeed portion of the fence is set further away from the operator than the outfeed fence. This difference determines the depth of cut. Most shapers allow you to “micro-adjust” the fence settings for perfect results.


          When shaping irregular (not square) work pieces, you will have to work freehand which is inherently more dangerous than using the fence. To do this, you will probably need to remove the fence or, at least, set it back, out of the way, toward the rear of the table. You will need to construct an alternate kind of safety guard and this can be made from a round piece of 3/16” or thicker Plexiglas with a hole drilled through it at the center point. This guard must be a bit wider than the swing of the cutter. It should be mounted at the top of the cutter or cutters on the spindle and then fastened down with the spindle nut. Keep your fingers as far away from the cutter as possible while maintaining a firm grip on the work piece at all times. With the rub collar or ball bearing installed, you can press the work piece into the cutter without worrying about going too far.


          A shaper can be an extremely dangerous machine if not used properly. Anything I say in this piece or anywhere else should NOT be construed as giving advice that could lead one to do anything dangerous, harmful, injurious or fatal. In, fact, I would say that if you are ignorant of the dangers present in woodworking or are not willing to take the necessary safety precautions, then you should immediately give up woodworking and never go near a woodworking machine again. Here are some precautions you MUST take when using a shaper in the interest of your safety and that of others in your shop:


          1) ALWAYS use some sort of guard or, even better, a power feeder. A power feeder will completely cover the cutter danger area and will push the work piece against the fence as it pushes it through the cutter. Buy a power feeder and use it whenever you can. When the operation precludes the use of a power feeder, at least use an effective guard. Most shaper fences come with guards. Use the guard!


          2) Most shapers can be run forward or reverse. This is because some cutters or cutter configurations require that the shaper be run in reverse. Before you start any cut DETERMINE THE PROPER DIRECTION OF ROTATION for the cutter or cutters on the spindle. Then check and double-check that the machine is set to the proper cutting direction. If you feed a work piece into a shaper WITH the direction of rotation instead of AGAINST it, the shaper can easily pull the work piece out of your grip and send it flying like a missile through your shop with possible FATAL results.


          3) NEVER shape small or thin pieces. Instead, shape a larger piece of wood than you need and then rip off what you need on the table saw. Small pieces can also easily become missiles. Further, they will cause your fingers to be way too close to the cutter and if they slip, they may cause your fingers to go into the cutter.


          4) USE A STARTER PIN when doing free hand work with irregular work pieces. It will give you much greater control and may prevent kick-back.


          5) USE A MITER GAUGE WITH A HOLD_DOWN CLAMP whenever shaping the ends of narrow pieces like table or chair legs. To attempt this without a miter gauge and clamp is asking for a trip to the emergency room.


          6) USE JIGS WHENEVER POSSIBLE. A jig is a shop-made or other device designed to guide cuts for consistent and safe results.


          7) USE EYE AND EAR PROTECTION and wear a DUST MASK. The reasons should be obvious.


          One more piece of advice, although this doesn’t relate to safety as much as it does to work piece conservation. Always shape (or rout) the end grain of a square or rectangular work piece first and then rout along the sides. This way, you have a good chance of shaping or routing away the chip-out at the end of the end grain as you clean up the sides. Also, if you are shaping end grain, try to clamp a back-up board to the work piece so that it passes through the cutter immediately after the work piece, thus preventing chip-out. If you can afford it or think you might be doing a lot of end grain cuts, consider a machine with a sliding table. In a mass production setting, it can pay for itself quickly in time saved and repeated accuracy.




Bob Gillespie
Woodworker

For similar articles and tool reviews see:

http://www.perfectwoodworking.com/





© 2010 Robert M. Gillespie, Jr.

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