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When doing a production job— like making wheels for a fleet of toy trucks—it is a time-saver to fasten the pivot to the trammel rather than to the work. That way you don't have to set down the rouier to pull the pivot and move it Also, it's easier to press the pivot into the hole in the work than it is to get the pivot into one of a dozen holes in the trammel.

layout all the circles and mark thccentcrpoints.Set up the router, including pivot installation. Make a first pass on all the circles, moving quickly from circle to circle. Set the router down to flip the work over, and make a first pass on the second side. Now reset the bit for a deeper cut. and repeat the whole sequence.

How do you get the pivot to slay m the trammel? Thread the hole in the trammel, and use a machine screw with its head cut ofias the pivot. To make it a pivot point, grind the tip to a point before sawing off the head.

TRIMMER TRAMMEL FOR SMALL CIRCLES

PITS RVOBI TILT-&ASE LAMINATE TRMME.R

TRIMMER TRAMMEL FOR SMALL CIRCLES

PITS RVOBI TILT-&ASE LAMINATE TRMME.R

* TRAMMEL TURNS YOUR ROUTER INTO A COMPAQ

)k~ PLYWOOD OR UARO&OAKO

* TRAMMEL TURNS YOUR ROUTER INTO A COMPAQ

)k~ PLYWOOD OR UARO&OAKO

What is shown in the photo above is the result of the quick but tidy approach. The task begins the same—cutting the plywood blank and laying out the head from the router baseplate. But then the trammel is cut to an elongated teardrop shape on the band saw or with a saber saw. And a series of pivot holes are drilled. After being bull-nosed, 1 x 1 braces are glued to the edges. Finally, a finish is applied

Adjustable Trammel

What you will probably discover if you use the trammel often enough is that the fixed size is sometimes a nuisance. So the next step is to make a trammel with interchangeable arms for different ranges of arc size. This way you don't have to deal with 5 feet of arm sticking out the back when you're cutting a 10-inch radius. Two-foot. 4-foot, and 6-foot arms will cover most of your needs nicely, and it's no problem to make longer ones if you need them.

But what about shorter ones? With your pivot point on a sliding block, the smallest radius you can cut is limited by the size of the base, right? Not really. Fred's trammel design demonstrates that it's a simple matter to make a pivot block that reaches a couple of inches under the router base, enough that you

With a large trammel making a wide arc, the most secure pivot is a screw driven into the work. You can use Iwth hands to operate the router without worrying that the trammel will jump off the pivot, allowing the router to forge its own route through the workpiece.

can get the pivot point within an inch of the cutter. 1 can't think of many reasons to want to trammel-cut an arc smaller than that.

This design is indeed clever. Fred's shop colleague Phil Gehret made two prototypes: one that accommodates a laminate trimmer; the other, a l'/i-horscpower Porter-Cable router. (Both the fixed base and the 6931 plunge case will fit the trammel baseplate shown.) Naturally, you can easily modify the shape of the trammel baseplates to suit other brands and models of routers.

The key to adjustability is the pivot base. It has a clamp that pinches the arm between its jaw and the pivot base. A couple of turns of the plastic knob will loosen the clamp so you can slide the pivot back and forth on the arm. Remove the two machine screws that attach the ami to the router baseplate and you can switch to a different arm.

To make the bigger trammel, yxw need a few scraps of good-quality '/♦-inch plywood, several strips of straight-grained, defect-free hardwood (Phil used oak), and a handful of hardware.

1. Cut the parts to the sizes indicated on the Cutting List. Remem* ber that the hardwood needs to be straight-grained and defect-free so it won't warp.

2. Remove the factory baseplate from your router, set it on the plywood baseplate blank, and trace around it. Mark the mounting-screw hole and the bit opening. Lay the arm in place on the edge of the plywood baseplate and mark it to ensure you leave a big enough tab fot it. Mark the locations of the two mounting' screw holes on both the baseplate and the arm. Mark off the quadrant that will be cut away.

3. Cut the baseplate on the band saw or with a saber saw. Drill and countersink the mounting-screw holes. In the arm. drill holes large enough to accommodate the T-nuts.

Setting the adjustable trammel is a matter of measuring from hit to pivot. (With a tape, it's usually more accurate to avoid using the inch with the hook.) Slide the pivot base as necessary to get the correct setting, thai tighten the lock knob.

Setting the adjustable trammel is a matter of measuring from hit to pivot. (With a tape, it's usually more accurate to avoid using the inch with the hook.) Slide the pivot base as necessary to get the correct setting, thai tighten the lock knob.

Tiif adjustable trammel's pivot can't be driven securely into the work, so it's a good idea to keep a hand on it as you rout. Use both hands to plunge the bit, then hold the pivot with one while pushing or pulling the router uif/i the other.

4. Glue the hardwood strip and the plywood clamp base to the pivot base, as shown in Adjustable Trammel.

5. Cut the clamp on the band saw, then drill the hole for the carriage bolt.

6. With a V*-inch Forstner bit, drill thecountcrborcs for the carriage bolt head and for the flange of the last T-nut. The T-nut must be flush with the bottom of the pivot base, but because the plywood is thin, you must be careful not to bore too deep. Drill the hole for the body of the T-nut and for the carriage bolt.

7. Glue the T-nut in the hole with epoxy. After the glue dries, file away the portion of the T-nut that sticks above the pivot base, and round off the comer of the pivot base to the edge of the T-nut. Before turning the thumbscrew into the T-nut. grind or

CUTTING LIST

Piece Number

Thickness

Width

Length

Material

Arm 1

Yi"

Yt"

24"

Oak

Clamp jaw 1

W

2"

3"

Oak

Pivor strip 1

Yi"

Yi"

5"

Oak

Pivot base 1

Yi"

VA"

5"

Plywood

Clamp base 1

Y."

2"

2Yi"

Plywood

Router baseplate 1

Yi"

5 Yi"

6Yi"

1 pc. Y*"-20 plastic knob, with blind hole. Available from Rcid Tool Supply-Co.. 2265 Black Creek Road. Muskegon. Ml 49444 (800-253-0421). Part #DK-59. 3 pes. 10-32 T-nuts 1 pc. 10-32 wing nut

1 pc. 10-32 X 1" thumbscrew

2 pes. 10-32 X 1" flathead machine screws file its rip to a sharp point, and grind away the ends of the thumb pad so the screw can be turned down between the wings of the wing nut. Turn the wing nut onto the thumbscrew, then turn the thumbscrew into the T-nut. Finally, drive the carriage bolt into the pivot base, set the clamp in place, and turn the knob on the bolt. Slide the arm into the channel under the clamp and cinch it down.

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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