Feed Direction

When doing any template-guided wuik. you waul the bit to pull the tojter toward the template. When you are routing around the outside edge of the workpicce. this

/\ fcnof that blemishes an otherwise excellent board can be excised and replaced with a carefully matched patch using inlay techniques. Guided by a template, rout an irregular recess that removes the defect. Using the same template, rout an insert with grain that matches the board as closely as possible. Can you sec the already-completed patch here?

/\ fcnof that blemishes an otherwise excellent board can be excised and replaced with a carefully matched patch using inlay techniques. Guided by a template, rout an irregular recess that removes the defect. Using the same template, rout an insert with grain that matches the board as closely as possible. Can you sec the already-completed patch here?

can also remove defects like knots by inlaying a patch of the same wood.

When the desire to inlay burns within you, take up your router first. The router is especially useful when the project involves multiples of the same shape. It's a template-guided operation.

With a template in the shape of your inlay and the right combination of bits and bushings (or bits and bearings), it's possible to rout bcth the insert and the recess for it. Ycu cut both with the same template. Once the template is made, you can cut the same shape again and again. Best of all, the inlay is always a perfect fit. This template technique has all sons of applications, both practical and decorative. The primary restriction is that without some handwork. the inlay can't have a radius in it smaller than that of the router bit.

The concepts used to inlay shapes may be a little trick)' to visualize at first. If Frank Rohrbach's drawings don't help, get out your router, a bit or two. and a set of guide bushings, and use them as visual aids. This technique is worth understanding.

You car use any router, plunge or fixed-base. But if you have a choice, a small router is most manageable. In most cases, inlays are fairly small, and it seems silly to cut them with a 3-horscpower plunge router. Of course, a plunge router does make it easy to begin the recessed cut, but it isn't really difficult to do with a fixed-base router. Most laminate trimmers will take guide bushings, and you may consider using one of these, if you have one.

Not all inlay work involves an enclosed shape. In some situations, you rout a shallow groove and glue a strip of material in it. You don't really need a template for this, but you can use a template rather than a fence to guide the cut. String inlay is a variation on this. Instead of a straight groove, you rout a narrow, winding groove, then carefully oend the insen strip to the contour of the groove, insen it. and trim it flush. This is a cut to guide with a template, as we'll see presented. Let's inlay a shape first.

Offset

The critical concept in this process is offset. And you have to go a little further with it than is neccssary fot simple template-guided work. There the offset is the difference between the line of the cut anc the line of the template. To calculate that offset, you just subtract the bit diameter from the bushing's outside diameter and divide the difference by 2.

Here, you work with the same offset dimension for both the recess and the insen, but you come by the measurement two different ways, depending upon whether you arc calculating the offset for the recess or for the insert.

1MLW OFFSET: HOW IT WORKS'.

LARGE-DIAHETER GUIDE BUSHING

LARGE-DIAHETER GUIDE BUSHING

SETUP FOR ROUTING RECESS

SETUP FOR ROUTING RECESS

5MALL-01AMETER GUIDE MSUING

FOR CUTHNG RECESS, I MEASURE FROM OUTSIDE JDFfSETW- OF BUSHING TO NEAR CUTTING EDGE-

5MALL-01AMETER GUIDE MSUING

SETUP FOR ROUTING INSERT

OFF in

SETUP FOR ROUTING INSERT

OFF in

FCR CUTTING INSERT. I MEASURE FROM OUT!K WISHING TO FAR CUTTING EDGE.

TEMPLATE 'EDGE

FOR CUTHNG RECESS, I MEASURE FROM OUTSIDE JDFfSETW- OF BUSHING TO NEAR CUTTING EDGE-

FCR CUTTING INSERT. I MEASURE FROM OUT!K WISHING TO FAR CUTTING EDGE.

TEMPLATE 'EDGE

Bit

Bushing

Bushing

Diameter

for Recess

for Insert

Offset

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W

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• For the recess, the offset is measured from the outside edge of the bushing to the nearest cutting edge.

• For the insert, the offset is measured from the outside edge of the bushing to the farthest cutting edge.

^BrM) RAWER

If you want to try a small inlay project without getting caught up in the math, buy an inlay kit. The lat from CMT, which is pretty much like those from other sources, includes a V»-inch spiral cutter and a special brass guide bushing with a removable collar. The bushing is two sizes in one. prefigured to give the conect offset for the bit. (See "Sources" on page 337 for information on CMT.)

You use it just the way you would use two complete bushings of different sizes. To rout the recess, you use the bushing with the removable collar pressed onto the one that's integral to the bushing. Then to cut the insert, you pull off the extra collar. One bit setting takes care of both cuts. Hie hardest part is making the template (of course)!

The guide bushing is in the Poner-Cable style and will fit any router that accepts the Porter-Cable guides.

The offset measurements must be equal. If they are equal, and you have measured each correctly, then the insert will fit perfectly in the recess. To make it a little easier for you, here's a chart (abo\'e) that lists five combinations of bushings and bits that you can use for this work. As long as you use the bit size listed with the two bushing sizes listed, you won't have to do any math. These combos will work!

The offset dimension itself isn 't important. What is important is that the recess offset be equal to the insert offset. It's also important that the cutter be of true dimension. A lot of bits arc jjuuussst slightly undersized, and that can create a misfit in inlay work. The insert offset will be less than the recess offset, so the insert will be a hair too big.

Cutting the Inlay

After creating your design and determining the offset you'll use. make the template. You use the same materials and techniques for this template as you do for any other. You only make one, arid you use it to cut both the recess and the insert.

Rout the recess first. Clamp, tack, or tape the template to the working stock. Remember that the actual recess will be smaller than the template, so position the template accordingly.

Set the depth-of-cut using a scrap of the template stock and the insert stock. Hold the two of them together on the router baseplate, right next to the bit. This will visually confirm diat the guide bushing collar is shorter than the template is thick. Then set the router on the workbench with the two pieces under it. Lower the bit until it just touches the bench top. The just-righ t setting is a trifle less than the insert thickncss. Assuming you are going to scrape or sand the inlaid surface before applying a finish, you need to have the insert just a bit proud of the surrounding surface. So back the bit up off the bench top by the thickness of a couple of sheets of paper.

There are two stages to routing the recess. The bit choices we've proposed are what you need to outline the shape. But if you want to excavate a 2-inch-square recess, a Mfr-inch bit will make it a daylong venture. So use a large-diameter bit. set to the just-right depth of cut, to clcan out the bulk of the recess. You can probably handle this freehand, meaning you don't need to use a guide bushing. If you do this work first, you have to be very careful not to cut too close to the template. Remember that there's offset between the edge of the recess and the template. It doesn't hurt to cut the outline first, then remove the rest of the waste.

Routing the recess couldn't be wore straightforward. The template is clamped to the worh, the router set up with bushing and bit. Set the depth of cut, then rout out the recess.

When you cut the outside, keep the bushing firmly against the template. You don't want any little pimples along the edge. Vacuum or blow all the chips out of the reccss, and run the router around the edge a couple of times. I:eed clockwise, remember.

Rout the insert. This is the dicey job. First, you're cutting around an internal template, but the piece you want is the internal pan. This means that the slightest drift from the template will ntin the part you want. Also, you don't want to actually cut the inscn free. If you do. it will likely shift as it comes free and be gouged by the bit.

To get stancd on this phase of the operation, change to the smaller-diameter guide bushing. If you can do this without changing the bit setting, that's good. You want to use the same depth setting if you routed the recess a little less than the insert thickness. This means that when you rout out the insen. you won't actually cut completely through the stock. The insert won't shift, and it won't get dinged. (It also means you won't rout into whatever the stock is clamped to—like your workbench.) The virtually paper-thin layer of wood holding the insen to the stock will be easy to cut through with a knife.

You do have to retract the bit to change the bushing? Don't sweat it. Just reset it. And keep it just shy of the depth necessary to cut through the insen stock.

Remove the template from the stock with the recess, and transfer it to the insert stock. Clamp everything securely. If you want, as an alternative to not completely freeing the insen with the router cut, you can bond the insert to a piece of expendable material with double-sided carpet tape. Make sure the insert area is bonded securely. Now when you cut completely through the insert stock, the insert will stay put. And the scrap will be routed instead of your bench top.

The insert can be cut from any piece of stock; it doesn't have to he thin. Rout what will be the insert in any stock of the right grain and color and size, cutting alwut'/«inch deep. At the hand saw, stand the stock on edge and cut a slice about Vs inch thick. As it clears the blade, the insert will fall into your hand.

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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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