Info

X s Vi length of minor axis YsM length of major axis ROUTER SETTING = distance from centerpoint to layout line along major axis. (NOTE: Refer to drawing to determine bit placement)

All measurements are in inches.

All measurements are in inches.

FIG. 2: MAKING THE PARTS

STEP 1: Draw parts full size on '¿-in. plywood using jig. Bandsaw templates for each mirror part

STEP 2: Lay out parts on VA-in. thicknessed stock. Mark axes as shown in red. Then cut out blanks, allowing about 'A in. around each piece for trimming.

STEP 1: Draw parts full size on '¿-in. plywood using jig. Bandsaw templates for each mirror part

Cut templates where joints will be.

mirror to scale. Then I sketched the approximate ellipses 1 wanted in the boxes.

From my sketches I scaled the major and minor axes of each ellipse and used these dimensions to determine the slide settings for the ellipse jig. Then I used the ellipse jig to draw full-sized mirror parts—the mirror frame, the stretcher, and one leg half— on '/»-in. plywood to sec what the final mirror would look like. (See Fig. 1 and 2.) This way, 1 could adjust the jig and pencil settings to produce the most pleasing appearance.

When I was satisfied with each ellipse, I noted the major and minor axis dimensions on a schedule. (See Fig. 1.) This gave me all the information I needed to set up the jig, so no formal blueprints were ncccssary.

Making the Mirror

The first step in constructing the mirror is to create tracing templates for each part, so you can lay out and cut blanks for routing. Begin by bandsaw-ing the templates from the full-size drawings you made on the '/i-in. plywood. Note that on the leg halves you have to draw the curved ends freehand and draw the straight edges where the halves will be joined. (Sec Fig. 2.) Make sure to mark the locations of the ellipse axes on the templates.

Trace each template onto lVWn. stock as shown in Fig. 2, Step 2, and transfer the axis marks from your templates to these blanks as shown in the drawing. You'll need the marks to position the blanks on the jig. Bandsaw the blanks, leaving about lA in. extra around each piecc and in. extra at the flat part of the stretcher.

Next, join the pieces to make blanks

Position eaeh part for routing by aligning it* major axis with the jig centerline and measuring from the renter point of the platform to the layout line oil the blank. A wood block elevates the ruler.

for the mirror frame and the stretcher. I used butt joinery with floating tenons, but you could also dowel the joints with '/¿-in. dowxrls or use splines. True up the mating surfaces on a disc sander or with a block plane. Dry-assemble the parts to make sure all the joints are tight, then mark out and plunge rout the mortises. Finally, glue up the blanks, using angled clamping blocks held on with hot glue to direct the clamping pressure. I used yellow (aliphatic resin) glue throughout the construction of the mirror.

To position each blank for rout-

STEP 2: Lay out parts on VA-in. thicknessed stock. Mark axes as shown in red. Then cut out blanks, allowing about 'A in. around each piece for trimming.

Cut stretcher blanks Va in. wider than template here.

mirror frame top and bottom

Draw ends of leg halves freehand.

Cut stretcher blanks Va in. wider than template here.

mirror frame top and bottom

Draw ends of leg halves freehand.

STEP 3: Join minor frame and stretcher blanks from their component parts. Use floating tenons, dowels or splines.

STEP 4: Align axis lines on blank with center-lines of platform. Attach Nank to platform with hot glue or screws.

Rout each part by plunging the router in Vic-in. increments and rotating the platform through the arc from one end of the blank to the other.

Rout each part by plunging the router in Vic-in. increments and rotating the platform through the arc from one end of the blank to the other.

ing. first refer to the ellipse schedule to determine the half-lengths ("X" and "Y") of the major and minor axes for the ellipse you're cutting. (See Fig. 1.) Now place your blank on the jig platform and measure these distances along each axis from the center point of the platform to the layout line on the blank. The axis lines of the blank should fall on the centerlines of the jig's platform. (See Fig. 2, Step 4.)

To make measuring easier, I cut a 1-in. by 1 k-in. by 6-in. block of wood to elevate my steel ruler to the height of the blank. By placing one edge of the block along a given axis of the jig, with one end of the block on the opposing axis, I could easily position my walnut blanks according to the dimensions given in the ellipse schedule. (Sec photo, opposite page.)

Once you've positioned the band-sawn blank, trace its outline on the platform. Turn the blank over, put a few small spots of hot-melt glue on its underside, and quickly press it into position inside the traced outline.

Now you're ready to set the jig and rout the ellipses. First, align the long axis of the platform with the cali brated slide. Next, set the slide to the slide setting listed in the ellipse schedule and lock it with the suitcase latch. Firmly attach your plunge router to the router arm and place the arm on the spacer block, with the router resting on the work. Set the cutting edge of the router bit on the interaction of the axis line and the layout line on the blank. (See Fig. 2, Step 4.)

Now clamp the router arm firmly to the spacer block and bench, checking to see that the router baseplate rests flat on the work. If it doesn't, add or subtract spacers as necessary.

With the router switched off and the bit retracted, swing the platform through the arc of the ellipse to make sure the bit follows your tracing line. If it deviates slightly, you can compensate by fine-tuning the slide setting.

(NOTE: If your router arm assembly is rigidly built and clamped tightly to your bench, you should be able to rout the mirror parts without assistance. I suggest a trial run with some scrap-wood to test your setup and build some confidence with the procedure.)

To cut the legs and stretchers, begin routing at cither end of the blank. (The mirror frame itself is a closed oval and has no ends, so you can start anywhere.) Plunge the router about /16 in. into the wood, lock the plunge mechanism, and rotate the platform steadily through the curve until the router bit just exits the other end. Without raising the bit or turning off the router, rotate the platform back to the starting point and take another plunge. Then rotate the platform in the opposite direction to its original position. You'll find it much easier to turn the platform if you grip it on the side opposite the router.

Don't try to remove too much material at a pass. You'll just overwork the router or burn the bit. More importantly, the torsional forces generated by too deep a cut could overpower the clamps holding your router-arm or change the adjustment slide setting, causing the bit to wander. 1 found */Win. plunges about right for my combination of walnut, a 3-HP router, and a not-too-sharp Vi-in. carbide straight bit. At this rate, it'll take you about eight passes to cut completely through a 1'¿-in.-thick blank.

After rounding over the stretcher, use a spokeshave to contour the last several inches at each end.

When routing the mirror frame, position the glued-up blank facedown on the platform of the jig. "ITiis way, you can rout the outside and inside ellipses and the rabbet for the mirror without changing the position of the blank. Rout the rabbet at the same jig setting you used for the inside cutout, simply moving the router position % in. further away from center.

After routing the mirror frame, drill /Win.-dia. holes about 1 in. deep, on the minor axis points, for the threaded inserts you'll use to attach the mirror frame to the Icg-and-stretchcr assembly. (See Fig. 1 and 4.)

After routing all the walnut parts, make a back panel to fit in the rabbet behind the mirror. I used inexpensive Vein, plywood because I intended to cover it with fabric, but you could make a fancy veneered panel if you like. Father way, take your unfinished back panel, or a paper pattern made from it, to a local glass supplier to use as a template for cutting a piece of single-strength ('/it in.) mirror. The mirror should cost around $60.

The next step is to round over and chamfer the edges of the walnut parts as shown in Fig. 1. Don't use the jig for these cuts—ball-bearing-piloted bits do a quicker and better job.

You'll find that the ends of the stretcher are too thin to round over safely with a hand-held router. The trick is to stop the router about 6 in. from the ends and finish rounding over with a spokeshave and block plane. (See photo, above.) Then bandsaw the Va in. of waste material from the straight outside edges of the stretcher

Clamp blocks handsawn from scrap lumber direct clamping pressure to the glue line. Threaded rods (hidden) through pivot holes keep parts and blocks in alignment for clamping.

FIG. 3: SECTION THROUGH MIRROR FRAME

Round over Va in.

Attach mirror and with Lexel or

FIG. 4: SECTION THROUGH PIVOT ASSEMBLY

Tap threads in wooden knob and epoxy threaded rod in

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