Making the Chassis

Tedswoodworking Plans

16.000 Woodworking Plans by Ted McGrath

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With the materials and hardware in hand, get busy in the shop. Build the chassis first, then the router mounting boaid

I. Cut the parts. I recommenced high-quality plywood to you for the wooden components. Here's why:

The plywoods I specified—Baltic Birch and Apple Ply- ! have a greater number of plies than standard birch plywood J (in the '/4-inch thickness, nine versus live). And the plies are all void-free. The result is a stiffcr material. The key to I success in combining precision components such as the linear-motion pillow blocks and steel shafts with a wooden I chassis is to use a highly stable and very stiff wood product Bob built his mortiser using Baltic Birch plywood,glue-laminating four '-4-inch pieces to form the various I

CHASSIS PLAN VIEWS

SIDE VIEW A

TOP VIEW

SIDE VIEW A

FRONT VIEW B

Lateral-travel adjustment rod

Chassis side Vertical-adjustment rod B -

BOTTOM VIEW 1H"

#6xK"

panhead screw

#6xK"

panhead screw

W-16 X 19" threaded rod

Chassis back

Knurled nut

Check nut

Chassis side

FRONT VIEW B

Lateral-travel adjustment rod

Chassis side Vertical-adjustment rod B -

BOTTOM VIEW 1H"

W-16 X 19" threaded rod

Chassis back

SIDE VIEW

Knurled nut

Check nut

Chassis side

10"

5" II H"-16X6'/4" threaded rod

components. In making the poor man's version, we used ordinary birch plywood. One of the notable failings of the poor man's version was the flexibility* of the chassis and the mounting board. For our final version, shown in the various photos. I used Apple Ply and recaptured the rigidity of Bob's original mortiser.

So. from the proper plywood, cut the plies for the chassis parts to the dimensions specified by the Cutting List.

2. Glue-laminate the chassis sides and bearing plate, the bearing plate is made up of two plies; each chassis side, of three.

Before glue-laminating the chassis sides, you must slot the middle plies for the mounting holts, as shown in the drawing Chassis Side Layout. This can be done on the router table or on the band saw. The slots arc supposed to dosely accommodate ^icrinch hcx-hcad bolts: don't cut them too loose.The bolt heads should be oriented as shown in the Assembly Detail of that drawing, with flats sliding into the notches and with points projecting out of the ply on each side. When the plies are laminated, those points will dig into the outer plies, helping to lock them so the bolts won't twist. (Such twisting would be a distinct problem when you install the chassis beneath a workbench.) The shank of each bolt should project iVu, inches beyond the open end of its slot. When the completed chassis is mounted under a 1 '/¿-inch-thick bench top, the bolts will be recessed about l/s to -Vi<> inch.

Widi the slots cut. you can glue up the two chassis sides. Spread glue on the appropriate faces of the plies. Slip the mounting bolts in the slots, and sandwich the parts together. Because of the bolts, you won't be able to trim the top edges of the chassis sides, so align the three plies very carefully. You can, of course, true the other three edges after the glue sets.

Glue-laminate the two plies forming the bearing plate.

3. Drill the chassis sides. The most critical parts that you'll be making arc the chassis sides.Thcy ensure that the shafts are absolutely parallel and that the plane of the bearing plate is perpendicular to the bench top. To achieve the needed accuracy, mark the inner faces, and tape or screw the sides together, inner face to inner face. That way. you can work on them as one unit.

With the sides taped or screwed together, trim them to

CHASSIS SIDE LAYOUT

TOP VIEW

Glue up 3 plies to form each chassis side.

SIDE VIEW

yi6"X3 W hex-head bolt

10"

6"

&"-dia. hole for shaft ft"-dia. hole for adjustment rod

&"-dia. hole for shaft ft"-dia. hole for adjustment rod

10"

Slot for mounting bolt

Outer ply

Insert mounting bolt in slot in inner ply, then sandwich it between the outer plies.

ASSEMBLY DETAIL

Outer ply

Insert mounting bolt in slot in inner ply, then sandwich it between the outer plies.

INNER PLY LAYOUT

BEARING PLATE LAYOUT

FRONT VIEW

The precision of the chassis sides is critical to the accuracy of this fixture. To ensure that the holes for the shafts and the lateral-travel adjustment rod align perfectly, tape the sides together and bore these holes in both pieces at the same time. And do the boring on a drill press.

length and width, then lay out the holes shown in Chassis Side Layout.

Before boring the holes, cheek to ensure that your drill press table is perpendicular to the drill, and use a fence when boring the shaft holes to keep them the same distance from the edge.The shafts should fit snugly in their holes.

Then separate the sides.

4. Install the inserts in the bearing plate. The router mounting plate is attached to the fixture with three studded knobs dial turn into threaded inserts in the bearing plate. Trim the bearing plate to its final size, squaring it in the process. Then drill and install the inserts.

See the drawing Rearing Plate Ixtyout for the specific locations of the inserts. Lay out and bore the pilot holes, using the diameter of bit specified for the inserts you arc using (a Vi 6-inch insert usually requires a '/¿-inch-diameter pilot hole). You can bore the holes completely through the plate.

Install the inserts next. A special wrench can be purchased to drive inserts, but a cheap solution is use a hex-head boll of the appropriate size chucked in a drill press. See the photo on page 127 for details.

Before setting the bearing plate aside, drill the hole for the vertical-travel adjustment rod. Lay out the hole as shown in Rearing Plate Layout, then drill it with a Vinch bit.

5- Assemble the shafts, pillow blocks, and chassis sides. LJnpack the shafts and the pillow blocks. As you do so, bear in mind that the pillow blocks arc sensitive to dust and dirt.They have excellent dust seals, which will keep out dirt once they arc mounted on the shafts. But you have to keep them clean before they are mounted on the shafts. So clean up your work area before you open the packages. And as soon as you unwrap a pillow block, slip it onto a shaft. It's as simple as that.

5/i6M-20 brass threaded inserts

BEARING PLATE LAYOUT

FRONT VIEW

5/i6M-20 brass threaded inserts

BOTTOM VIEW

Glue up two Vim plies to form the plate.

H"-dia. X 11«"-deep hole for adjustment rod

Glue up two Vim plies to form the plate.

Stand the chassis sides on their back edges.

Install the lower shaft first. Slide the shaft into the lower hole in one of the sides. Fit a pillow block onto the shaft, then slide the shaft into the lower hole in the other side Move the two sides as necessary to position the sluft flush with their outer faces.

Poke a ^-Inch-long *6 panhcad screw into the scam between the wood and the steel shaft. Drive the screw between the wood and steel; it will bind the two parti together. In the same fashion, drive a screw to lock the other chassis side on this first shaft.

The second shaft is installed in exactly the same war, except that this shaft—the upper one—has two pillow blocks on it.

Once a screw has been driven at each end of both shafts.you'll find that the chassis ends stay in position at the outer ends of the shafts.

6. Mount the pillow blocks on the bearing plate. Set the bearing plate face down on the workbendj (the face has the inserts in it).

Set the chassis assembly over the plate. Align the pilloi blocks on die plate, as shown in the Section Views. The upper pillow blocks should be spread apart and positioned all fx* at the edges of the plate. The lower pillow block should ht centered. There should be an equal amount of space abo* the upper blocks and below the lower block. Most import* of all, the plate should be square to the axes of the shafts.

SECTION VIEWS

SECTION A-A

Bearing plate

SECTION B-B

Thomson #SPB 12 linear-bearing pillow blocks

MOUNTING BLOCK DETAIL Bearing plate

Thomson #QS Va" L 12 steel shaft

Lateral-travel adjustment rod

Mounting block

locking the shaft in the chassis side is accomplished with a screw driven into the seam between the parts, as shown. The screw takes up enough space to jam the shaft in the hole, but it can't in any way mar the hardened steel of the shaft.

Mounting the pillow blocks is a straightforward screw-driving process. With the bearing plate on a flat surface, set the chassis assembly in place, line up the pillow blocks, drill pilot holes, and drive the screws.

Because the bearing plate is proud of the chassis sides, the front edges of these pans should be balanced about Ha inch off the bench top.

Drive a couple of screws into each pillow block to told their positions.Then slide the chassis back and forth. Make sure the inner faces of the chassis sides are parallel to the edges of the bearing plate. If they aren't, if the chassis is slightly cocked on the plate, withdraw the screws and realign things.Then redrive the screws—run them into different holes on this second try—and check the alignment again.

When the alignment is tested and proven correct, tighten down the screws holding the blocks. Drive and tighten the rest of the screws.

SECTION VIEWS

SECTION A-A

SECTION B-B

Thomson #SPB 12 linear-bearing pillow blocks

MOUNTING BLOCK DETAIL Bearing plate

Bearing plate

Thomson #QS Va" L 12 steel shaft

Lateral-travel adjustment rod

Mounting block

Custom-fit the adjustment-rod mounting blocks to the mortiser as it takes shape. With the rod roughly centered in the chassis-side holes, slide the bottom half of the block under the rod. as shown. If it won't fit, shave the bottom with a block plane. When it fits, set the top half in place and screw the block to the bearing plate.

7. Install the lateral-travel adjustment rod.

Without moving the chassis assembly, slide the threaded rod that will serve as the lateral-travel adjustment rod through the holes in the chassis sidcs.Thc same length of rod should extend beyond the plate on each side, of course. This rod is fastened to the bearing plate with mounting blocks.

Cut the mounting blocks to rough shape, and drill the pilot holes for the mounting screws. But don't drill the holes for the adjustment rod or halve the blocks just yet.

Instead, wedge the adjustment rod so it is roughly centered in the holes in the chassis sides. The idea is that the rod should move back and forth in those holes without restriction when the mortiser is in use. Measure from the plate to the center of the rod (it should be in the neighborhood of -/it. inch). Lay out the centerpoint on the mounting blocks, and drill a -'«-inch hole through each.Then with a hacksaw, saw each block in two, halving this hole.

Slip the bottom parts of die blocks under the rod, locating them at the outer edges of the plate, as shown in die Section Views. Set the mounting block tops in place, and drive the screws, securing them and the rod to the bearing plate.

8. Make and install the back. Like the rest of the wooden parts, the back is glue-laminated from two pieces of '/¿-inch plywood. For the best fit. it's best to wait until this point in the project to cut the two plies.

Measure the chassis. One ply fits between the chassis sides, while the second ply overlays them, fitting flush with their outer faces. Cut the pans to the correct sizes, then glue diem face to face. A half-doz.cn small nails driven through the plies will hold them in alignment while the glue sets, and permit you to complete the assembly right away.

Set the back in place and scrcw it fast. Using just screws—no glue—allows you to remove the back at a later date, should it become necessary.

9. Epoxy the vertical-adjustment rod into the bearing plate. This is the last chassis part to be inMalled Cut the threaded rod to the specified length, and epoxy it in its stud hole in the bottom edge of the bearing plate. I If your epoxy is the thin, runny kind, paint the inside of the drill holes thoroughly, and leave at least 1: inch of epoxy in the bottom of each hole. Faint the rod end with epoxy. and insert it gently into the hole: don't push it

ROUTER MOUNTING BOARD LAYOUT

FRONT VIEW

Rout '/¿"-deep recess for router base.

5/i6"-wide slots

10 va"

BOTTOM VIEW

ROUTER MOUNTING BOARD LAYOUT

FRONT VIEW

Rout '/¿"-deep recess for router base.

5/i6"-wide slots

10 va"

BOTTOM VIEW

W-dia. hole for mounting screw

ADJUSTMENT PLATE DETAIL

ADJUSTMENT PLATE DETAIL

W-dia. hole for mounting screw

thick aluminum down fast, which would force air into the hole and squirt out cpoxy.

If your cpoxy is the thick, pasty kind, drill a small vent hole into the bottom of the stud hole, and smear both the inside of the stud holes and the rod end with the paste, and then push it in. Wipe up the excess.

Let the epoxy cure at least 24 hours before disturbing the assembly. Epoxy doesn't require any kind of clamping, but it really does take many hours to cure.

After the epoxy cures, turn the pairs of special nuts on the adjustment rods, horizontal as well as vertical. Turn the knurled nut on the rod first, then the check nut. In use, you make the adjustment with the knurled nut, then jam the check nut against it to hold the precise setting.

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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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