Constructing a Wainscot Door
The Quadraset is an adjustable slot cutter with four stacking cutters. It works like a mini dado set for the router. The four cutters, 1/8”, 5/32”, 3/16”, and 1/4", can be used individually or stacked to create cuts from 1/8” to 23/32” in 1/32” increments.
First, the bit is set for cutting a 3/8” tongue-and-groove on the frame members. Then the bit is setup for cutting a 1/8” tongue-and-groove on the wainscot strips. The final step before assembly is to shape a bead on one edge of each of the wainscot strips with the corner bead bit. Let’s get started.
Mill the Stock
Your best door begins with stock that is flat, true, and square. In other words, if the stock is warped or twisted the completed door will never fit the opening properly. This is why I avoid surfaced two sides (S2S) stock. Instead, I use rough stock and mill it myself; this way I can flatten the stock on my jointer before planing it to thickness. When making a stile-and-rail framework for a door I always mill a couple of test pieces out of inexpensive stock such as poplar. The test pieces serve as samples when setting up the router table.
When selecting stock for doors, I choose straight-grained material that is free of knots or dramatic figure. I’ve found that straight-grained stock works best because it resists warping. After flattening the stock on the jointer and planing it to thickness, I joint one edge and rip it to width. The final step in milling is to cut the stock to length. When milling stock for doors, I always make the stiles about an inch longer than the height of the door. The extra length provides “ears” which allows for easy disassembly of the framework after dry fitting; it’s also easier to trim the excess length of the stiles flush with the rails after assembly rather than aligning the corners during glue-up.
The length of the rails is critical because it determines the width of the door. I calculate the rail length as follows: Door width minus 2x stile width plus 2x depth of panel groove.
Cut the Frame Joints
Before cutting the joints on the door frame you’ll need to set up the Quadraset to cut a 3/8” slot. First lock the bit shank into the router collet. Follow the instructions with the bit to stack the necessary cutters followed by the guide bearing. Remember to position the cutters to face counter-clockwise when viewing the bit from the end with the spindle nut. With the cutters, spacers and guide bearing in place secure the assembly with the spindle nut.
Next, adjust the height of the bit to cut the slot in the center of the stock thickness and cut a slot in a sample piece. You’ll use the sample piece to test the fit of the tenons when routing the ends of the rails. Next, adjust the bit height to cut the tenon so that it fits snug within the sample groove. Using the miter gauge to support the workpiece, make a cut from each face of the stock and test the fit of the tenon in the panel groove. If necessary, adjust the height of the bit to add or subtract thickness from the tenon and check the fit a second time. Once the fit is precise cut the tenons on both ends of each of the rails.
The next step is to shape the wainscot strips for the door panel. The strips measure 3/8” thick by 2” wide. To determine the length of the strips I assemble the door frame and measure to the bottom of the groves in the rails. When milling the strips to thickness I use the panel groove as a guide to ensure a snug fit; the wainscot strips should not be loose in the completed door.
After milling the strips I use the 1/8” cutter on the Quadraset to cut a tongue-and-groove joint on the edges of the strips. Afterwards I shape the bead on one edge adjacent to the tongue.
Before assembly I smooth the surfaces of the wainscot strips; they will not be easily accessible after assembly. Also, it’s best to apply the finish to the wainscot before assembly. Otherwise an unfinished surface will be exposed the first time the panel strips contract during the dry winter months.
During glue-up I’m careful to clamp the door on a flat surface in order to avoid gluing a twist into the door. Also, I apply the glue sparingly and carefully to avoid excess glue reaching the wainscot and gluing it in place. Once the glue has dried I trim the stiles flush to the edges of the rails.
Tools used for this technique.Quadraset Router Bit #53600
Corner Bead Router Bit #54163