47 - Build Your Own Mortising Machine , страница 18

47 - Build Your Own Mortising Machine , страница 18

FEATURE

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I began by makin g the base of the mortising machine. The base provides a mounting surface for a metal track that guides the sliding tables, see drawing. In addition, it serves as a foundation for a tall, vertical tower that houses the router carriage.

FRAME. The base starts out as a simple plywood frame. The front and back (A) of this frame are identical in - size, see Fig. 1. But to allow clearance for a handle, you'll need to cut a long notch in the front piece.

The front and back are connected by four rails (B) that are notched to accept the metal track. To prevent the table from binding, it's important for these notches to line up.

An easy way to accomplish this is to first mount a dado blade in the table saw. Then butt each rail against a stop block clamped to a fence on the miter gauge, see Fig. 2. After making a single pass for each rail, reposition the stop block and make a second pass to complete the notches.

SUPPORT BLOCK. Before assembling the base, I added a plywood support block (C) to hold the end of the handle. After notching the support block to accept the handle, ifs screwed to the two inside rails to form an H-shaped assembly. Then just screw the rails to the front and back.

FEET. This is also a good time to add two feet (D) to the bottom of the

Fh WOOD-SCREW

\

\

base, see drawing above. These long strips of plywood extend past the base so you can clamp the mortising machine to your bench.

TOWER

Once the base is assembled, the next step is to add the tower. Basically, it's a tall, open box that provides rigid

#3xV/z" FRONi^ Fh wood- IB

screws ^r

support for the carriage assembly.

SIDES. The main parts of the tower are two L-shaped sides (E). To cut the long "leg" of each side, I ran a large plywood blank against the rip fence on the table saw, see Fig. 3. But because the saw blade won't make a square corner, I stopped the cut about 1" from the layout line.

back

(93/4" X 2V/2"-%" PLY.)

#& x 11/4" Fh WOOD-SCREW

METAL TRACK GUIDES SLIDING TABLES

foot

x 23"-

#3 x Fh WOOD SCREW

CAP DETAIL

w ©

11/a

hole

side

support block

(4V2" x e3A"-

PLYWOOD)

CENTER AND CUT

..........NOTCH,

'/2"-DEEP

rail

(4V2" x IV/2"-5/4" PLYWOOD)

#3 x W Fh WOODSCREW

front

(4Vz" x 24"-%" PLYWOOD)

DADO BLADE

18

ShopNotes

No. 47