Raising Panels

Panel raising is a router table operation. In a nutshell, to work a rectilinear panel, you set the fence and bit. clamp a couple of featherboards in place, and rout. Outside of the nutshell, there's a little more to it.

Deal with the bit first. As far as I am concerned, the bit you use dictates which router table you use. With the horizontal bit. you use the regular router table. With the vertical bit. you use the horizontal table. These dictates have to do with the angle of attack. They allow you to keep the work flat on the tabletop.

With a small workpiece. this may not seem too critical. But consider some typical work. My kitchen has 42-inch wall cabinets with 3fr-inch-high panels in the doors. I have a pantry cabinet with a pair of 60-inch-high doors with 56-inch-high panels. Just think about holding those panels against a router table fence, even if it's a foor high. Yoiks! Panels that big arc the reason you want to keep the work flat on rhe tabletop.

To reiterate: If you have a horizontal bit. use the regular router table, and if you have a vertical bit. use the horizontal table.

If you plan to use a horizontal bit. make sure your router will accommodate it. You need high horsepower and speed control, as we've noted several times. But the router'sstnic-ture has to accommodate it, too. The mounting plate's bit oper.ing will undoubtedly have to be bored out to accept a 3!/:-inch-diameter bit. But check the router, too. All the big plunge routers except the Porter-Cables have some restriction to the bit opening. Usually it is tabs for mounting a template-guide adapter. A big panel-raiser will hit these tabs, and you don't want to be there for the collision.

Here's trouble. The opening in the base of this table-mounted router simply isn't big enough to really accommodate this large panel-raiser. You can see a portion of the guide bushing mountingjlange under the bit. This integral part of the base casting clearly intrudes into the space the hit needs. Recognize the potential for mctal-to-metal conflict here, and avoid that at all cosLs.

Here's trouble. The opening in the base of this table-mounted router simply isn't big enough to really accommodate this large panel-raiser. You can see a portion of the guide bushing mountingjlange under the bit. This integral part of the base casting clearly intrudes into the space the hit needs. Recognize the potential for mctal-to-metal conflict here, and avoid that at all cosLs.

BIT DRAWER

A panel-raising bii is serious business. It is as big a cutter as you will buy. and it represents as big a cut as the router can make. It's a big investment. It can be a dangerous investment.

Panel-raisers are available in two configurations: horizontal and vertical. The horizontal bits are more widely available than the vertical bits, and they are made in a much greater variety of sizes and profiles.

Horizontal panel-raising bits. If what you are used to is standard straight, round-over, and cove bits, the size is the first thing you notice about a horizontal panel-raiser. As bits go. it is huge. The GMT horizon ral panel-raiser shown in the photo is just under Wj inches in diameter and weighs 11 ounces. That's a lot of metal to spin.

The size of these bits is their drawback, of course. A high-horsepower router is required to drive them. A 3V:-inch bit spinning at 22,000 rpm is moving about 230 mph at the cutter tips. When you bend the path of that whizzing cutter around a 3-inch circle, you begin to develop centrifugal forces that put some pretty serious strain on the materials holding it together. Just think about a carbide tip pulling loose and you'll understand why most manufacturers recommend limiting the larger cutters to 10,000 rpm. To do this, obviously, you must use a variable-speed router (or a speed control).

In addition to urging you to operate the biggest of the horizontal panel-raisers at a reduced speed, several manufacturers. Freud and CMT among them, configure their bits to limit the size of the chip that can be taken. By restricting the bite, the designs

CMT HORIZONTAL BIT

FREUD HORIZONTAL BIT

EAGLE AMERICA UNDERCUTTER

CMT HORIZONTAL BIT

FREUD HORIZONTAL BIT

EAGLE AMERICA UNDERCUTTER

EAGLE AMERICA 3-WING SHAPER CUTTER ON A ROUTER ARBOR

EAGLE

AMERICA

VERTICAL

CASCADE SY HORIZONTAL BIT WITH UNDERCUTTER

EAGLE AMERICA 3-WING SHAPER CUTTER ON A ROUTER ARBOR

EAGLE

AMERICA

VERTICAL

CASCADE SY HORIZONTAL BIT WITH UNDERCUTTER

reduce the chance for kickback. Eagle America enhances the chip-limiting feature by making its largest cutters in a three-wing design. The extra cutting edge helps smooth the cut made when the bit is spun at 10,000 lpm.

The reason these bits arc so big is, of course, the demand for a wide reveal. If you want a IVi-inch-wide reveal—it's pretty standard in the cabinet industry, where shapers are used to raise panels— you need a bit that's just about 3'/j inches in diameter. A smaller bit will suffice if you are willing to accept a narrower reveal—1M® inch, for example, or 1 inch, or inch.

The widest assortment of profiles is Fagle America's, with 20 variations of ogee, bevel, and cove profiles in three different reveal widths. Most other manufacturers list three to six profiles in a couple of sizes. The point here is that you need not feel limited to a beveled reveal; you can have an ogee, a cove, or any of these shapes with a bead around rhe panel's field.

Vertical panel-raising bits.

You don't need a high-horsepower, variable-speed router to raise panels. With a venical panel-raiser, a lVj-horsepower, fixed-speed router is all you need.

That's because the venical panel-raiser, while still pretty massive, is small in comparison to an equivalent horizontal one. Although, at a cutter height of 1 Vi inches, it's taller than the horizontal bit, it's usually no more than 1 Yi inches in diameter. And that reduced diameter is the whole point. Driven at 22.000 rpm, the tip speed of the venical bit is just under 100 mph (compared to 230 mph for the horizontal bit).

The bit shares the operating concept of rhose architectural molding cutters. The cut's "width" is dictated by the bit height rather

CLASSIC 0«Et

RAISED PANEL PROFILES

CLASSIC 0«Et

RAISED PANEL PROFILES

than by its diameter. The bit designer is simply changing the angle of attack. The vertical panel-raisers currently on the market will cut a standard 1 Vz-inch reveal (but nothing less). Available patterns include ogees, coves, and standard bevels.

The typical vertical bit has two flutes. Because it has no pilot, it has to be used in conjunction with a fence, and it cannot be used to raise the edges of curved panels.

At this writing, only Byrom and CMT have vertical bits in their catalogs.

An interesting twist on the vertical concept is offered by Eagle America. It is a "3 in 1 Moulding Cutter Kit" that comes with three different bearings. The bit will produce 18-degree chamfers, as well as forming chamfered moldings and raised panels. The pilot would seem to be pointless for panel raising, however, since it s about 1 Yi inches above rhe tabletop.

Undercutters. A subset of the horizontal panel-raisers arc those with undercutters. The undercutter is a bit that produces a recess much like a rabbet on the back of the panel. This allows you to use W-inch-thick stock for panels without having to cut excessively deep with the panel-raising cutter. The undercut panel ends up licing flush with both the face and back of the frame.

A few bit vendors—Cascade, for one—mate an undercutter with a horizontal panel-raiser, putting both cutters on the same shank. Some woodworkers believe this bit's configuration, which places the work between two cutters, is hazardous. Fred figures that with the proper hold-downs, you shouldn't have problems. It's wonh noting that with this bit, you creep up on the final cut depth not by adjusting the bit height but by shifting the fence position. (As an alternative. Fred suggests removing the undercutter for the firsr two or three passes. Reinstall it for the final pass only.)

An undercutter can be purchased as a separate bit from Eagle America. You use it after raising the panels to the degree that suits your aesthetics, and relieve that panel back as necessary to size the tongue.

This doesn't mean you can't use these routers for the job. It does mean that the mounting plate's thickness is a big part of your margin of bit-height adjustment. Even with the bit set as low as you can get it, you may still be cutting the full 1/2-inch width of the reveal on the first pass. So making a shallow pass may require you to overcenter the fence on the bit, so you're addressing less than the full reveal width. For the second pass, move the fence back, and for the third, begin raising the bit.

Not all router bases have these obstructions, of course. The base of the big Porter-Cable production router we use in our main router table would accommodate an even bigger bit (if someone were foolhardy enough to make it and we were foolhardy enough to use it).

Set the bit to a height appropriate for the first pass. Depending upon the router, set the bit either as low

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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