There are two good reasons to acquire the skill of making moldings on the router table. One is that it enables you to reproduce profiles for repairing furniture or architectural millwork. The other is that it allows you to incorporate elegant moldings into new work without being limited by stock shapes.

Quite often, commercially available moldings appear different from historic profiles because much of their detail has been lost. A molding that has been fed through a sticker machine has not only lost its crispness, but also the play between light and shadow — not so when molding is made with a router.

Begin by arranging the complete profiles of more than one cutter together. Depending on the scale, this can either be a single piece of wood or several pieces built up to produce the required size.

Figure 1

For example, the profile shown in Figure 1 was a common late-19th-century door panel mold composed of an astragal and reverse ogee. It
is one of the easier moldings to reproduce, and illustrates the importance of the cutting order of the individual pieces. In this case, the astragal is milled first, allowing the ogee bit to cut to the required depth. Be sure to take several passes to complete heavy cuts and that the stock is supported, and keep your fingers clear of the running bit by using a push stick. To complete the molding, the bearing must be removed from the ogee cutter to ensure that the top curve is as full as possible. Without doing this, the S-curve becomes half-hearted. Sometimes the pilot bearing gets in the way, and so plunge bits (like a core box) tend to be more versatile than guided cutters (such as a cove).

Figure 2

Figure 2 shows a built-up molding of a chair rail. Since this one requires a bit more planning, it's helpful to draw each section in order to visualize the final result. To determine the cutting sequence and whether the moldings are all run from the same end, take a piece of stock of the required size and put the router bits up against it.

Another technique is to blend different shapes together smoothly in the same piece of material. Sometimes the entire surface of a bit is needed, whereas other situations might call for only certain portions to be used. This requires a careful set-up for the height of the cutter and the location of the fence since the awkward junction of two shapes leaves a line that draws the eye.

Figure 3

The profile shown in Figure 3 is a large reverse ogee and cove as would be found on a brick mold. The best approach is to cut the concave curve of the ogee first, using a core box bit. This will also leave a nice even surface below it. Use a plunge round over to complete the ogee. This is actually a two-step process that involves cutting a rabbet with a straight cutter to remove the waste and then gluing wooden support pieces to the fence in order to support the workpiece and keep it from tipping. Cutting the cove on the edge is easy enough, but again, support pieces are needed on the fence.

Once in a while a situation comes along that seems to defy even the most creative lateral thinking. Usually, it involves an element that either curves back over another or cannot be reached by a conventional router bit guided by a fence. Before having a cutter custom made, consider whether the problem can be solved by running the piece at an angle. For some situations, simply ripping a bevel of the required angle on the table saw and using that face down on the table is enough, but for others a carriage must be built.

Figure 4

The fence in Figure 4 holds the stock at the correct angle and supports it as it passes the bit. Like the other more complex techniques for making molding, using it means a bit of planning in terms of cutting order and having the needed tooling on hand, but the end results will be well worth the extra effort. A.S.

 

 

 

 
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