A raised panel floats in the grooves along the stiles and rails. The purpose of this construction is to allow for expansion and contraction across the width of the panel without splitting the door or affecting its size, which is fixed by the stiles and rails. The key is to have the edge of the panel be a snug sliding fit in the groove so that it can float, but not rattle.
Horizontal vs. vertical panel-raising setups
To make raised panels on the router table you will need a panel-raising cutter. Two types-horizontal and vertical-are available, and each has its advantages and disadvantages. With horizontal panel-raising bits, the panel is run horizontally, with the face down on the table and the edge against the fence. They generally require less setup than vertical bits, and most have a pilot bearing for running arched panels. If you have a correctly made panel to use as a model, all you have to do is put the edge against the pilot bearing and raise the bit until it just touches the rise. Now place the fence well forward of the bearing and take the first pass. Move the fence back successively until on the last pass the panel edge touches the bearing. If you are guiding off the pilot bearing you will have to start with the cutter low and raise it on successive passes. This will require care on the final pass not to make the edge too thin, which would yield a panel that would rattle in its frame.
The concept of the vertical panel-raising bit has been around for a long time and comes to the router table from shapers. It is so called because the panel is held vertically during milling, with the face against the fence and the edge on the table. The advantage of the vertical panel raising bit is that it can be of much less diameter so that less power is needed and higher speed can be used. Vertical panel-raising bits have some disadvantages, too. They generally require an additional light pass for a good finish. If heavy cuts are taken, the bits will chatter, especially the 1-inch. dia. bits. Vertical bits require a little more setup, such as a special high fence and feather boards positioned to press above the terminus of the rise. If the bit has a bearing, the fence is adjusted to it with a steel rule. If there is no bearing, adjustment is by trial and error. Finally, vertical panel-raising bits can only be used on rectangular panels. Arched panels must be done with a horizontal bit.
All panel bits, vertical or horizontal, require three to five passes, and the fence or bit height must be reset each time. A light final pass will make for a superior finish, especially on the cuts across the grain. Light cuts are especially important when working off of pilot bearings. Heavy cuts make pilot bearing work uncontrollable.
In conclusion, the choice whether to use a vertical or a horizontal bit will be dictated by the shape of the panel and the horsepower of your router more than anything else. The photo-essays that follow show an arched panel door milled with a horizontal bit and a rectangular panel milled with a vertical bit.
Raising an arched panel with a horizontal cutter:
- Cope the ends of the panel first, guiding it along with the pilot bearing with the aid of a fixture attached to the panel with double-sided tape. A shop-made guard with dust-collection pickup shields the horizontal panel-raising bit. The last step is to finish the cut.
Raising a rectangular panel with a vertical cutter:
- Raise the ends of the panel, using a piece of scrap the same thickness as the panel as a backing block and pushstick. A featherboard clamped to a riser block presses the panel square against the fence above the terminus of the rise.
- Raise the sides of the panel, again using a backing block/pushstick
- Finish raised panel.
An arched frame-and-panel door
Arched panel doors can add a custom decorative touch on kitchen cabinets, as a center door in the cubbyhole of a desk and elsewhere in your house, and you can make them in whatever wood and size you want. They make an interesting break from straight lines. As shown in the Six-step photo-essay that begins below, the frame for an arched panel door can be made quickly on the router table by first shaping the rough bandsawn arch with a pattern and a flush-trim bit, then sticking the inside edge with a sticking cutter and finally coping the ends of the rails. When an arched panel is inserted in the frame, the door is done.
Making an arched frame
- With a vacuum fixture atop the roughly bandsawn blank, rout the edge of the arched top rail with a flush-trim bit.
- Stick the groove and profile on the inside edge of the arched top rail. The stiles and the bottom rail have been stuck in a normal fashion, using a fence.
- Stick a backing block to facilitate the coping of the end of the arch. This backing block was bandsawn to the same radius as the panel. It will both hold the arch end square and back up the end of the cut. During sticking, the block is being held by the RTG Handle
- Install the backing block in the arched rail to facilitate coping.
- Cope the end of the arch with a backing block in place, using a quick and dirty miter gauge to push the arched rail past the bit.
- The finished frame, partially disassembled to show the joinery. The piece in the middle is the backing block, which can be used to cope another arched rail.
Source: The Router Table Book