Overarm Pivot

Tedswoodworking Plans

Ted's Woodworking Plans

Get Instant Access

One kind of pivot point that doesn't harm the table's surface is the overarm. Instead of being under the work, the pivot is on top of it.

A job-specific overarm pivot can be made using a strip of 14-inch plywood and a scrap of the working stock. Drive the pivot point through the plywood, then tack or screw the plywood to the scrap. The distance from the pivot to the scrap has to be long enough to accommodate the workpiece, of course.

The big advantage to this system is that it also provides a positive hold-down for the work. If you set one clamp well back from the work, you can usually spring the arm enough to get the work under it. Then set a closer clamp to secure the setup. The work won't jump off the pivot.

Having an adjustable overarm pivot on hand can save you some time. Phil Gehret made us a simple but effective jig that has an overarm joined to a base block in a sliding dovetail. You slide the base along the arm, setting it to suit the job. Then clamp it to the tabletop. The clamp not only holds the jig on the tabletop but also secures the arm-to-base setting. The pivot is a thumbscrew with a point ground on the end.

Mary Jane Kelly
Set the overarm jig on the tabletop, measuring from hit to pivot point to align it. Set tw o clamps on it to keep it from sniveling out of position. Then slip the workpiece under the arm, and turn the pivot down into it.

AN OVERARM PTVOT FOR ROUTER-TABLE CIRCLE WORK

karpwooo BASE

AN OVERARM PTVOT FOR ROUTER-TABLE CIRCLE WORK

karpwooo BASE

the router table and raise the bit a little more. Turn the blank again. Eventually, following this sequence,. the bit comes through.

This works well with a plunge router, because the micro-adjusting knob raises the bit straight up into the work. Moreover, it raises the bit with a mere tum of the knob; you can raise the bit with one hand while holding the work with the other.

Fixed-base routers present wo problems in this regard. One is that you need two hands to adjust the cutting depth, so you can't make the adjustment with the machine running. The other is that fixed-base routers generally have sidcplay when you loosen the clamp to raise the bit. The motor—and thus the bit— can jiggle from side to side. The bit thus can gouge the work.

Few real limits exist on the circle work you can do on the router table, though there definitely are some practical ones.

Too small a circle puts your fingers in jeopardy. All 1 can advise is that you try manipulating little disks next to a stationary bit and develop your own sense for this. Some of my colleagues wouldn't cut anything smaller than about a foot in diameter; I've done 6-inch disks without qualms. 1 do 2- to 3-inch wheels with the trimmer trammel. These are your fingers, and even with a bit guard, you can get them into the bit if you let your concentration lapse even for a moment.

Another practical limit is at the other end of the size scale. Too big a circle ranges beyond the capacity of the tabletop. Measure from the bit to the far corner of your router table. That's the maximum radius you can cut without resorting to some son of supplementary tabletop.

oval cutting

An oval (or ellipse) is a two-dimensional geometric shape, an enclosed cunt with a continuously changing radius It's a wonderfully plastic shape. A circle is always a circle; only the size changes. But an oval can be all-but-a-circlc, or it can be extremely elongate. One of my colleagues here at Rodale, Bob Moran. triers to ovals as "squashed circles."

Bob's the one who got us started making squashed circlcs. He talked about a jig he had made back in his professional woodworking days, which he used to cut oval tabletops. oval frames, and the like. The cutting tool he used was the router.

Most woodworkers know how w draw ovals using two tacks and some string. But those same woodworkers probably think that to actually cut out an elliptical form, you have to draw the ellipse, make a template, trace it out on your work-piece. band-saw the rough shape, and flush-trim to your template. With this jig you can rout a geometrically correct ellipse, directly. All you need tokno.v is its length and width.

Oval-Cutting Trammel

Moran came across this idea when he was thumbing through an old book on carpcntry. Back in the eighteenth century, Benjamin Asher was teliing carpenters how to build a jig lofdrtrsing ovals. When Bob saw it. he adapted it for the router.

That's what he says, anyway. To the res of us. the jig bears a striking recmblancc to the old "BS grinder" ordo-r.othing machine. It's got two keys that travel back and forth in perpendicular slots. They're con-

nrrrrd byan arm What's intending, and surely something you never realized when grinding a load of BS. is that the ami traccs out an oval.

The adaptation for the router is a blessing when you want to make oval tabletops or oval frames. That's not BS.

The particular jig shown here is one Fred made. You can rout dovetail slots in medium-density fiber-board (MDF) or particlcboard or even real wood, but Fred cut strips of chcrry for the tracks and nailed them to a plywcod base. The use of thumbscrews and T-nuts enhances the easy adjustability of the jig. The thumb screws go through holes drilled in the trammel bar so the keys can pivot freely.

Let me explain how to set it up. (I'd explain how it works if 1 could; what 1 can explain is how to set it up. I think you'll get the picture from that.)

An oval has two measurements of particular importance in setting up the jig. One is the longest dimension. more properly called the major axis, and die other is the shortest dimension called the minor axis. Draw two ccntcrlincs on the stock, one the long way and one the short way. You position the two tracks

The structure of the oval-cutting trammel is pretty clearly exposed here: the dovetail-slotted tracks formed of separate strips, the plywood base, the router mounting, the trammel bar, and the sliding keys. Note the bushing on the long thumbscrew'; it reduces wear on the wooden parts, while freeing the mechanical action of the trammel.

Routing an oval doesn't demand more of the operator than routing a circle. You turn on the router, piling«* the hii, and move the router in the right feed direction. The action of the trammel, however, is considerably different. And as the slides rnovr back and forth in their tracks, barely missing each other at the crossing, the router follows a far different path.

24" 32"

TUE OVAL-CUTTING TRAMMEL'S RANGE OF SIZES

directly over the two centeriines. Then you fasten it there. If the area to which the jig is attached is waste, you can just nail the tracks to the stock. For tabletops, you can fasten it with double-sided carpet tape.

To set up the jig, mark the ends of the major and minor axes on the appropriate centeriines. Park the router ai one end of the major axis first. Insert a sliding key in the track that's perpendicular to the major axis. Line it up at the junction of the tracks, under the trammel bar. Then run a thumbscrew through the arm into the key.

Now move the router to one end of the minor axis. Insen the second sliding key in its track, line« up at the track junction, and mm thumbscrew through the trammel bar into it. This setup establishes the proportion of the oval, which is to say. the difference between the major and minor axes. You adjust the size of the oval by moving the router on the trammel rods.

The range of the jig is determined by the size of the trammel's base, the length of the tracks and the sliding keys, and the distance between the holes in the trammel bar. It is not infinitely variable. Rather, it is a relatively modest range ol proportions, a wider range of sizes. Let me explain.

Overarm Router Jig

TUUMBSCREW5

TRANSITION BLOCK

TRAMMEL RODS

SLIDING KEY

BEVELED TRACKS

* PLYWOOD

GRIND OUT TU05L OVALS WITU TUI5 OVAL-CUTTING TRAMMEL

TRIM POINTS OFF CORNERS.

ROUTER

TRAMMEL

Circle And Ellipse Cutting Jig

2ND SLIDING

MAJOR AÏIS-I5T SLIDING

INSERT TUUMBSCREV.

STEP 3: MOVE ROUTER TO END OF MINOR AXIS. SLIDING FIRST KEY ALONG ITS TRACK. INSERT TUUMBSCREV THROUGH TRAMMEL BAR INTO SLIDING KEY IN SECOND TRACK. FINE-TUNE TUE ROUTER POSITION AS NECESSARY BY SLIDING rr ON TRAMMEL RODS.

MINOR

MAJOR AXIS

BASE UNIT

SETTING UP TUE TRAMMEL

MINOR

MAJOR AXIS

STEP POSITION TRAMMEL BASE UNIT ON WORKPIECE. TRACKS OVERLAYING THE OVAL'S AXES.

MINOR

INSERT MAJOR

SLIDING

TRAMMEL

2ND SLIDING

MAJOR AÏIS-I5T SLIDING

Z» POSITION ROUTER ON END Of MAJOR AXIS; INSERT THUMBSCREW THROUGU TRAMMEL BAR INTO SUDING KEY IN TRACK PERPENDICULAR TO MAJOR AXIS.

BASE UNIT

INSERT TUUMBSCREV.

STEP 3: MOVE ROUTER TO END OF MINOR AXIS. SLIDING FIRST KEY ALONG ITS TRACK. INSERT TUUMBSCREV THROUGH TRAMMEL BAR INTO SLIDING KEY IN SECOND TRACK. FINE-TUNE TUE ROUTER POSITION AS NECESSARY BY SLIDING rr ON TRAMMEL RODS.

The shortest minor axis you can cut is established by positioning the router as close to the base as you can get it. Depending upon the router you use. you can't get the bit closer to the base than about 3 to V/i inches away. The diagonals for the base— and thus the tracks—are roughly 17 inches long. This adds up to 23 or 24 inches as the shoncst minor axis this jig will produce.

Given that minor axis measurement. the shoncst major axis you can get is 30 inches long. The determining factor? The length of the sliding keys. If you position their pivots closer together than 3 inches, they collide at the crossing. Trimming the keys from a 3-inch length to a 2-inch length would get you a closer setting. The disparity in radii doubles, obviously, when you talk about diameters (in this case axes), so the major axis ends up being 6 inches longer than the minor one.

Let's not leave that last factor unexplored. When you shift the pivots, you must move in 1-inch increments. The holes in the trammel bar are spaced that far apan. The 1-inch increment doubles when viewed in terms of axis length. The adjustability of the jig is therefore in 2-inch increments.

Given that 6 inches is the smallest difference between axes you can achieve, what's the greatest? Sixteen inches. The track length sets this figure. If you position the keys more than 8 inches apan. one will be out of its track.

Speaking in terms of oval proportions. then, this jig will range in 2-inch increments from 24 inches by 30 inches up to 34 inches by 48 inches.

You can rout larger ovals with the jig. The router can be moved out the trammel rods far enough to cut an oval with a maximum axis of 86 inches. The trammel rods are about 22 inches long, providing enough room to shift the bit position about 18 inches, so at any proportion setting, you have a 36-inch range in axis length. If you wanted to rout an oval frame, you would set the proportion and size to rout the outside edge, then slide the router in on the rods to cut the inner edge.

To make the trammel:

1. Cut the 14-inch square base from thin plywood.

2. Make the tracks and sliding keys. Use a hardwood, like maple orcherry, beginning with straight-grained, defect-free stock about Y* inch thick and V/2 inches wide. Mark the top surface of the stock. Set the table saw to cut a 7-degrec bevel, then rip a Winch-wide strip from the working stock. Turn the stock around, keeping the top up. and repeat the cut. The strips cut are the tracks; the "waste" will yield the two sliding keys. Joint the cut edges lightly to remove any saw marks.

3. Assemble the tracks and the base. Clamp a single strip of the waste to the base, positioning it diagonally. Miter the tracks as necessary to fonn the joints at the base's center. With a single sheet of paper between the waste and the rails to crcatc sliding clearance, butt the rails to the waste and nail them in place. When the first set of tracks is set, reposition the waste across the other diagonal and repeat the process to install the second set of tracks. Cut off the comers of the base assembly, as shown in Oval-Cutting Trammel.

4. Cut two keys, each about 3 inches long. Drill a hole for a thumbscrew through each, equidistant from the ends. Drive aT-nut into the bottom of the hole.

5. Make the transition block. Start by determining how big it needs to be. Fit the trammel rods into the holes for them in the router base, then measure the distance between them (labeled "D" on the drawing). Cut the trammel block 2 inches longer than your distance D.

The trammel rods slide through holes in the transition block that are kerfed, so the rods can be "clamped" in place. Drill holes for the rods and for the screws, then counterbore the latter holes for T-nuts. Kerf the ends of the bar. To do this on the table saw, crank up the blade to make a cut at least lYs inches deep. (The kerf should extend at least '/? inch beyond the hole for the pinch to be secure.) Set the Icnce so the cut will pass through the center of the hole. Stand the trammel block on end to make the cut. and use a scrap block to back it up.

6. Cut the trammel bar and drill 13 holes. 1 inch apart, for the thumbscrews to pass through. Glue and screw the trammel bar to the transition block.

Ellis 'n' Fred's Oval-Cutting Rig

Bigger, more flexible, and even more mysterious is this oval-cutting rig developed by Fred Matlack and Ellis Walentine. You know Fred. Ellis is an editor of American Woodworker, a custom cabinetmaker and furniture maker. Inspired by the basic oval-cutting trammel. Ellis and Fred worked to overcome its shortcomings and particularly to expand its range.

What they came up with will cut the largest oval possible from a sheet of plywood, as well as one smaller than the minimum size the previous trammel would. What a range! Unlike that trammel, which produced 1-inch-sized steps in proportion. this rig is infinitely variable. It allows you to rout ovals in a rnrv tinuous range of sizes and shapes, from Vi inch by 41/? inches to at leas 48 inches by % inches.

The most overt change is thai with this rig. the route: is fixed and the work moves. Simply adjust the jig for the shape of the ellipse, place your stock on the platform, set up the router, and rotate the platform. The stationary router creates the ellipse on the moving stock. You can cut an oval, rabbe: it for glass, even rout elliptical inlay grooves,all as easily as routing a circle.

The contraption consists of a base, a platfonn. and a separate fixture to hold the router over the platform. When you turn the platform. hardwood tracks attached to its underside slide back and forth on two dovetail keys screwed to the base. The platform therefore moves in an elliptical path. By changing the spacing of the dovetail keys, you can change the sJuj/>c of the ellipse. The size of rhe ellipse is de:ermincd by where you place the router.

To make it easier to change the shape of the oval. Fred and Ellis attached one of the dovetail keys to a strip that slides in and out of the base in a sliding dovetail. (The second key is fixed.) Pull the adjustment slide outward, and you move the first key farther from the second, thus changing the length of the oval's major axis in pmponion to the minor axis.

And to capture any setting, they installed a lock strip, which is so

Remember your old hi-fi's turntable with its tone arm? The o\aleutling rig is an eccentric turntable, with the router set up as ¡ketonearm. The workpiece is set on the platform, and the router is set on the workpiece. With the router switched on and the bit plunged into the work, the operator turns the platform, and thus the work. Instead of revolving on a steady axis, however, the rig's platform revolves on a shifting axis. Instead of a circle, it makes ano\al. Instead of following a groove, the router's lone arm makes a groove.

The tracks are attached to the bottom of the platform with drywall screws. To get all the pieces forming one slot parallel, and to ensure thai the slot is the proper width, use a strip of the slide stock, as shown here.

Remember your old hi-fi's turntable with its tone arm? The o\aleutling rig is an eccentric turntable, with the router set up as ¡ketonearm. The workpiece is set on the platform, and the router is set on the workpiece. With the router switched on and the bit plunged into the work, the operator turns the platform, and thus the work. Instead of revolving on a steady axis, however, the rig's platform revolves on a shifting axis. Instead of a circle, it makes ano\al. Instead of following a groove, the router's lone arm makes a groove.

simple that I'll have to explain how it works in detail a little later.

Two prototypes were built. The first has T-slot tracks, a fir plywood platform, and a plastic-laminatc-covered base. The second has dovetail tracks, a birch plywood platform, and a mclaminc-covcred panicle-board base. The following construction sequence (and Cutting List on page 176) represents a melding of the two versions, as does l:llis 'n' Fred's Oval-Cutting Rig. The photos show the T-slotted version.

To make the rig: I. Make the platform first, using >'*-inch plywood. Cut your platform to an exact 36-inch by 48-inch rectangle, and carefully lay out perpendicular centcrlines on one face. You'll center your tracks on these lines later. Continue your center-lines up the edges and across the top face of the platform.

2. Make the tracks next. Fred and Ellis used oak for the first-generation prototype, cherry for the second-generation rendition. Any strong, straight-grained, defect-free hardwood will do. It's imponant for the tracks to be perfectly straight, so rip them slightly oversized, then joint them and rip them to their finished dimensions.

Before routing the dovetail grooves in the tracks, remove as much waste as possible by cutting a Vfc-inch-wide by Mo-inch-deep dado down the center of each blank. Then rout the required slots with a 1-inch dovetail bit in a table-mounted router. If you don't have a 1-inch bit. you can make two passes with a '/2-inch bit, referencing from the same edge to keep the width of the groove constant. The rake of the dovetail isn't critical as long as you cut the sliding dovetail keys to a matching angle.

3. Make the dovetail keys next. These should slide in the tracks with no sidcplay. Taper the leading edges slightly with a file so they won't catch as they slide back and fonh across the intersection of the assembled two tracks. (To help you align the tracks during their installation, you may want to rout an extra—and extra-long—strip of the key stock now.)

4. The tracks are screwed to the bottom of the base next. Miter one end of each track. These points formed by the miters should be exactly 90 degrees and centered perfectly on the dovetail grooves so opposite tracks will line up. After cutting the miters, fine-tune them on a stationary disc sander.

Attach the tracks with l'/Vinch drywall screws, making ccnain the dovetail grooves are exactly perpendicular and centered on the platform's centcrlines. That extra strip of dovetail slide stock can help you line up the tracks, but Fred likes the eyeball method.

The tracks are attached to the bottom of the platform with drywall screws. To get all the pieces forming one slot parallel, and to ensure thai the slot is the proper width, use a strip of the slide stock, as shown here.

Overarm Router Plunge Router

WORKPIECE

PLATFORM

iitiom block

DOVETAIL KEY5-S>

yrplywooo arm

SPACER BLOCKS

W PLYWOOD BASE

DOWEL SLIOt HANDLE MAY BE TAPPED IN 0« OUT FOR FINE ADJUSTMENT OF SUDE. \

ADJUSTABLE \ DOVETAIL KEY FIXED DOVETAU. KEY

DOVETAIL LOCK STRIP

ClOSINC LATCU PULLS \

STRIP, JAMMING ADJUSTMENT \ SLIOE. \

\ ADJUSTMENT

PLATFORM

adjustment slide.

/ TUMI). /hlXEO DOVtTAIL KEY —" FLATHEAD WOOO SCREW DRIVEN^ INTO EPOXY-FILLED HOLE

LATCU IN i PULLS LOCK STRIP.

LATCU ATTACUED TO LOCK STRIP

OOVETAIL LOCK / STRIP Vt-*r*ift'

SECTION

TRACK

IT'S BIG! IT'S FLEXIBLE! IT'S ELUS'N'FRED'S OVAL-CUTTING RIG

5. To make the base, use a rectangular piece of plywood or other y*-inch-thick sheet stock. The first-generation rig has a plastic-laminatc-covered plywood base, while Ellis's second-generation unit has a mclamine-coated particleboard (MCP) base. Both provide a low-friction surface for smooth operation. Cut the base to size, and apply the plastic laminate to one side and backer to the other. (See the chapter "Router Table Design" for more about backer.)

6. Mark the locations of the fixed dovetail block and the dovetail grooves for the adjustment slide and the lock strip, as shown in Ellis V Fred's Oval-Cutting Rig. The adjust-

Vplywo*d platform

CUTTING LIST

Piece

Number

Thickness

Width

Length

Material

Platform

1

¥<"

36"

48"

Plywood

Base

1

W

30"

42"

Plywood

Tracks

4

2"

24"

Hardwood

Dovetail keys

2

w

1"

2 Yi"

Hardwood

Adjustment slide

1

wM

1"

40"

Hardwood

Slide handle

1

r-dia.

8"

Dowel

Lock strip

1

Vi"

1"

18"

I pc. 30" X 42" plastic laminate

1 pc. 30" X 42" laminate backer 32 pes. lH" drywall screws

2 pes. #8 x 1W flathead wood screws 1 suitcase latch epoxy

SECURE BASE TO BENCH •WITH SCREWS OR VISE

WUUJI

hej&ut as required ment slide's dovetail groove is on the base centerlinc, and it is cut into the top surface. The lock strip's dovetail groove is cut into the underside, about 3 inches from the edge; it intersects the adjustment slide groove and extends about 3 inches beyond it.

Rout the groove for the lock strip first, cutting it Vi inch deep by 1 inch wide. Make a hardwood slide for the groove—the lock strip. It should be flush with the bottom surface of the base. Slide this lock strip all the way into the groove, and clamp it.

Now turn the base faceup, and rout the groove for the slide bar, cutting it Vi inch deep by 1 inch wide. too. You'll cut through the lock strip when you do. Make the adjustment slide several inches longer than this groove. The length isn't critical, but the slide's fit should be just barely snug, not too tight.

7. Install a lock-strip latch. Here's how the strip works. When you insert the adjustment slide, it passes through the lock strip. If you could pull on the end of the lock strip, it would pull the adjustment slide to one side, tight against the wall of its groove. Then the slide would be immobilized. Locked in place!

The way you "pull on the end of the lock strip" is with a suitcase latch, which you should be able to pick up for a buck at the local hardware store. The catch ponion spans the lock strip itself and is screwed to the base. The latch is screwed to the strip. Be sure the cam action of the latch clamps the lock strip firmly against the slide bar and prevents it from moving. Any slippage in use will spoil your ellipse.

8. To attach the dovetail keys to the base and slide bar. first drill and countersink the keys for #8 by l'A-inch flathcad wood screws. To keep the screws from working loose, Fred seated their threads in epoxy. The epoxy "glues" them into the plywood base, yet the bond can be broken if you end up needing to remove the screws.

Before drilling pilots for the screws, push the adjustment slide all the way in; then mark the hole locations, one in the base and one in the slide, exactly 2 inches apan. Any-closer and the blocks will not clear each other when they rotate. Drill the pilots, then dribble a gob of epoxy into each. Rub all surfaces of the dovetail blocks with paraffin, then screw them down, snug to the base and slide.

9. The final step in preparing the base is to calibrate the adjustment slide. With the slide pushed all the way in. you should have exactly 2 inches between the centers of the fixed and adjustable blocks. Disc sand the nose of the slide bar if you need to reduce the spacing, or pull out the slide bar slightly to increase it to 2 inches.

Now, use a try square to scribe a line across the face of the slide bar at the exact point the slide bar leaves the base, and label it "4." Mark off 16-inch increments from this mark toward the dovetail block. Since the space between the two dovetail blocks equals half the difference between the major and minor axes of a given ellipse, each mark corresponds to a 1-inch difference.

10. Assemble the platform and base. With the adjustment slide removed, carefully line up one track opening at the nose of the fixed dovetail key. Slide the platform onto the key, stopping when the platform is centered on the base. Complete the assembly by insening the slide in its groove and pushing the adjustable dovetail key into the other track.

11. The last pan to make is the router fixture. The simple fixture Fred and Ellis came up with holds your router above the workpiece. The double-rod system, a common mounting for edge guides, lets you lock the router in position quickly.

To make the head, epoxy two rods (of a size that fits your router) into a lVi-inch by 2-inch by 5-inch block, then screw the block to a Winch by 3-inch by 60-inch plywood arm.

Markings on the adjustment slide make it easy to reset the proportion of the ellipse. Since each half inch movement of the slide translates into a fidl inch of difference between the oval's axes,you must mark the slide accord-ingty. Make marks at Vz-inch intervals on the slide, and write the appropriate numbers on the slide.

Set up the rig by first dogging the base to the workbench. Then install the platform. Do this by positioning the track at the nose of the fixed dovetail key (left) and pushing (or pulling) the platform so the key slides in the track. Next, align the cross-track with the slot for the adjustment slide. Start the slide into the slot, get its dovetail key nosed into the cross-track, and push the slide into place (right).

Set up the rig by first dogging the base to the workbench. Then install the platform. Do this by positioning the track at the nose of the fixed dovetail key (left) and pushing (or pulling) the platform so the key slides in the track. Next, align the cross-track with the slot for the adjustment slide. Start the slide into the slot, get its dovetail key nosed into the cross-track, and push the slide into place (right).

A 5-inch-high spacer block elevates the router fixture above the jig, so the platform—with workpicce in place—can rotate freely under the fixture. For routing thick stock, you simply add spacers to raise the fixture as nccessary.

To use the rig, you first must dog (or screw) the base of the assembled jig to the workbench, making sure the lock-strip latch remains accessible.

Lightly scribe a centerlinc on your workpicce. which will coincide with the major axis. Position the work on the platform, aligning its centerlinc with that on the platform. Attach the work with screws, double-sided carpct tape, or hot-melt glue. Set the adjustment slide for the desired difference between the major and minor axes. To avoid undue strain on the dovetail keys, always center the long axis of the platform above the slide before making adjustments. Then unlatch the lock strip, move the adjustment slide to the desired difference on the scale, and relatch the lock strip.

Before shifting die platform—the major axis should still be aligned with the slide—mark one end of the desired oval's major axis on the workpiece. Line up your router bit on the waste side of that mark.

Here's an example: If you want to rout an oval that's 18 inches by 24 inches, set the adjustment slide at 6 inches (the difference between the major and minor axes), and mark a point 12 inches from the center on the major axis.

Be sure you clamp the router fixture firmly to the bench. Stan the router, plunge the bit about V* inch into the work, and rotate the platform slowly and evenly in a clockwise direction. To prolong the life of

your platform, don't plunge too much beyond the thickncss of the work. It's a good idea to cut a little outside your line and follow up with a final trim pass oncc you've plunged all the way through.

For cutting out ellipses, a fr or '/i-inch straight bit will work fine. If you'd like to chamfer or round-over the edge of your ellipse, use a handheld router and a piloted bit after you've cut out the elliptical shape.

If the ovals don't turn out quite as tidy as you had hoped, troubleshooting is straightforward. If the groove doesn't pass through the Stan-

The centctline of the platform must be centered over the adjustment slide when positioning the bit at the end of the ellipse's major axis. Otherwise the oval will be skewed. The routei fixture can be positioned at any angle. Remember that the proportion of the oval is adjusted with the slide. The size of the oval is adjusted by repositioning the router, as shown here.

Was this article helpful?

0 0
How To Sell Furniture

How To Sell Furniture

Types Of Furniture To Sell. There are many types of products you can sell. You just need to determine who your target market is and what specific item they want. Or you could sell a couple different ones in a package deal.

Get My Free Ebook


Responses

  • BOBBI
    How to build an ovalcutting trammel?
    5 years ago

Post a comment