Making the Straightedge

Tedswoodworking Plans

16.000 Woodworking Plans by Ted McGrath

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This jig is simply a plywood straightedge or fcncc with somcl home-brewed clamping blocks attached to die bottom.

In concept, it's like a pipe clamp. Here the work of the I pipe is done by the plywood fence. At one end is a fixed I head block. A threaded rod extends through this headl block.The rod has a pressure block on one end. a knob oq the other. Turn the knob clockwise, and the pressure block moves away from the head block. Turn it the other way,and the pressure block pulls back toward the head block.

At the opposite end of the fence is a tail block. This! block is attached to the jig by a single bolt that extends! through a long adjustment slot in the fence. Loosen the I knob on that bolt, and you can slide the tail block back and! forth on the fence.

To use the jig, set it on the workpiccc, just as you would! a pipe clamp. Move the tail block against the edge of the] work and set it. Then turn the knob to apply pressure at the! head end. and pinch the workpieee tightly.

What's appealing about this jig is that the pressure-! application mechanism uses standard hardware—a carriage] bolt, stop nuts, and a threaded insert. It's stuff that's avail-l able and cheap. And the mechanism works!

1. Collect the hardware. It's always a good idea to do your shopping before you begin. You may already ha« most of the hardware in your shop. Go out now and bur what you don't have. The local hardware will have everything but the knobs. And you just may find suitable substitutes there.

Fence

Tail block

Pressure block

Head block

Fence

Tail block

Pressure block

Head block

ROUTING STRAIGHTEDGE PLAN VIEWS

TOP VIEW

EDCE VIEW

BOTTOM VIEW

2"

If you've a mind to, go ahead and make your own wooden knobs. I happen to like the big plastic knobs that are becoming more and more common in woodworking catalogs.They are durable, provide great leverage, are easy-otvthe-hands, and arc not all that expensive.

2. Make the fence. I used shop-grade birch plywood. Substitutions are okay, but I'd recommend some type of plywood because it is stable and strong.

Cut your material to the dimensions specified by the Cutting list. You can, of course, make the fence longer or Shorter. If you make it about 56 inches long, you'll be able to use the finished guide across standard-sized sheet goods. But for smaller workpieces. you may find the extra length a nuisancc. 'I"hc range of the guide shown is 6Vi inches up to 36 inches.

Rout the slot next. I did this on the router table with a Scinch straight bit. Scribe lines across the straightedge, marking the ends of the slot. On masking tape applied to the muter table fence, mark the width of the router bit. Lineup the appropriate marks, plunge the work onto the bit, rout until the end marks line up. then tip the work up off the bit. Repeat the process, making incrementally deeper cuts until the slot is completed.

3. (optional) Apply laminate to the edges. I actu ally used my straightedge for quite some time before deciding to laminate the edges—to grease the skid, so to speak. The laminate dresses up the plywood edges, too.

Simply coat the edges with contact ceraent.and apply it to the backs of the plastic Laminate strips, too. When the cement is dry, stick the laminate to the plywood, burnish it with a J-roller, then trim the edges flush with a flush-trimming bit. Do the ends first. After they've been trimmed, apply the laminate to the long cdgcs.That way, the long laminate strips will overlap the ends of the short laminate strips.

4. Cut the clamping blocks. Use hardwood, though it doesn't matter particularly what hardwood. I made the head and pressure blocks from oak. l or the tail block, I rescued a poplar offcut from the scrap bin because it was just the right thickness and length. Cut these parts to the dimensions specified by the Cutting List. Note the grain direction.

5. Form the spine on the tail block. This block has a ridge or spine that fits into the straightedge's slot to keep the jaw from twisting.

To form the spine, I cut two rabbets on the table saw. With a hacksaw, 1 trimmed the spine back on one end, leaving it just under 2 inches long. So that the spine would nestle into the rounded end of the slot, I nnindcd the front end of the spine with a file.

Improve the clamp's grip with sandpaper. The short- ] coming of the jig's compression clamping system is the lack of traction on smooth wood surfaces. To keep the jaws from slipping out of position on the straightedge, and to improve the jaws' grip on the workpiece. glue sandpaper to the the jaws, as shown.

'¿^inch-diameter pilot hole.) Position the block under the bit. then bring the fence and stop block into place and clamp them. Clamp the workpiece to the fence. Bore the pilot just deep enough for the insert.

Switch to the bit for the clearance hole. If you need to. move the workpiece;but don't touch the fence or stop block. Drill the hole through. Set the head block aside. Pop the pits sure block into place, and drill the clearance hole through it

8. Notch the blocks. Both blocks must be notched to provide clearance for parts of the pressure mechanism, as you can sec from Assembly Detail. Notch the head block for the stop nut, and the pressure block for the bolt head The notches are the same width but different depths.

I cut the notches on the table saw. Set the blade heigh to match the depth of the notch. Stand the block on edge, and guide it across the blade with the miter gauge. Make repeated cuts to clear the waste.

9. Drive the threaded insert. This is a somcwh* dicey operation, because there is but a thin wall between the pilot hole and the surface of the block. It's easy to blow out that wall while driving the insert.

For a driver, use a short bolt with two nuts on the shank. Thread the bolt, with the two nuts already on it. into the insert. Jam one nut against the insert, then the second nut against the first. Clarnp the block in a vise. Use a wrench to turn the insert and bolt, and drive it into the hole When it is fully driven, unjam the nuts so the bolt can he

7. Drill the adjustment-bolt holes in the head and pressure blocks. As shown in the drawing Assembly Detail, the bolt that provides the pressure extends through holes drilled through the middle of the blocks. The head block has a two-part hole. The first inch is bored as a pilot hole for the threaded insert, while the remaining length is bored as a clearance hole for the bolt. The hole in the pressure block is a clearance hole for the bolt.

To ensure the holes will be properly aligned, set up a fence and stop block on the drill press table to position and hold the block being drilled.

Do the head block first. Chuck the bit for the insert pilot hole in the drill press. (The size of bit to use should be specified on the insert.The vb-inch inserts I use require a

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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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