Popular Woodworking 2003-04 № 133, страница 41
The typical router table setup works for dadoing parts like drawer sides. A push block - just a square scrap - stabilizes the work and backs up the cut, preventing tearout as the bit emerges from the cut.
Dado large workpieces on a router table with a cutoff-box-like sled.A stop clamped to the sled's fence locates the cut and immobilizes the work. Slides on the underside reference the edges of the tabletop to guide the sled.
sizing: Want a 1/2"-wide dado? Use a 1/l" bit. Want a dado for 3/4" plywood, which is typically under thickness? Use a 23/32" bit. Changing bits is quick and easy.
The tool also offers options on approach. If you have your router hung in a table, dadoing with it is much like table saw dadoing. But the router gives you the option of moving the tool on a stationary workpiece, and in many situations, this turns out to be the better approach.
On the Router Table
For a long time, my mantra has been that you can rout grooves on a router table more easily than you can dados. Consider the typical router-table setup. It's small in comparison to the typical table-saw setup, with its expansive infeed and outfeed tables. So I'd say, limit yourself to dadoing small parts only, things such as drawer sides.
Guided by the fence alone, you can easily rout grooves. The grain runs along a work-piece's long dimension, so a groove is easy to locate and cut guided by the fence.
But try guiding the workpiece's short dimension edge along the fence. Or locating a dado 16" from that edge. Or 24" or 30". Maneuvering a 6'-long bookcase side or a 24" by 36" base cabinet side on a router table top is a Keystone Kops routine. But a drawer side - where the piece is small and the dado (for the drawer back) is close to the end - can be routed pretty easily. You use a square-ended push block to keep the work square to the fence as you feed it and to back
up the cut. Large case parts are best done on the table saw or with a hand-held router.
Recently, however, I made a cutoff boxlike accessory for my big router table. I don't like miter gauges (or the slots they require) on a router table, so the dadoing box I made is guided by the tabletop's edges (see the drawing below). I've dadoed some pretty large workpieces with it. The setup was sim
Stop bar -
shift position right or left to locate cut, clamp to front fence
ple, the operation downright easy and the results were clean and precise.
This accessory is changing my attitude, I must say. It offers all the advantages of the table saw-cutoff box setup, but eliminates the trial-and-error with the stack set.
Back fence -11/2" x 11/2" x 30" hardwood
Slot for router bit -position varies from
table to table
Front fence -11/2" x 3" x 30" hardwood
1/4" plywood or MDF
7/8" x 1V4" x 30" hardwood Dado jig
42 Popular Woodworking April 2003