Table Saw Bowl

The Amazing The Amazing Tablesaw Tablesaw

BowlBowlIts just like sawing

a cove molding, but now the

wood is round.

by Richard Tendick

YOURE KIDDING ME! Th ats everybodys fi rst reaction when I tell them that Ive fi gured out a way to make a bowl on the tablesaw.

Th en they ask, Isnt it dan-gerous? Believe me, if it were, I wouldnt be writing about it. As long as you use my jigs and follow the simple instructions below to the letter, youll be perfectly fi ne.

Now to the harder question: Why do it? If you dont have a lathe, the answer is obvious. You really dont have to buy one if all you want to do is make a bowl. But if you do have a lathe, Ill think youll be intrigued enough by this process to give it a try. Its really amazing!

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Make the blankI designed these jigs for 8" x 8" turning blanks that are 3" thick (see Source, page 60). Blanks of this size are widely available and come in a variety of species. (Th e bowl shown here is made from padauk). I prefer to use wood that is thor-oughly drywet wood can clog up the jigs and might rust your saw. Many blanks arent dry enough; I recommend set-ting them aside until they are as dry as kiln-dried wood.

Caution: Dont use cracked or knotty wood for making this bowl. It could break apart during the sawing operations. In any case, wear safety glasses, goggles or a face shield.

Flatten both sides of the blank with a belt sander, electric plane or hand plane, or by using a thickness planer. If you use a planer, temporarily fasten 3/4" x 3" x 16" boards to both sides of the blank, to eff ectively lengthen the piece. On most planers, its not safe to mill pieces that are less than 12" long.

Cut the blank into a 7-5/8" dia. circle (Photo 1). When using the bowl-making jigs, youll get the best results if the blank is perfectly round. Cutting the blank freehand will work OK if youre careful and go slow, but making a perfect circle is a cinch if you use a circle-cutting jig. You can

buy one or make one yourself (see Source and Adjustable Circle-Cutting Jig, AW#158, February/March 2012).

Note that the blank is 1/8" smaller in diameter than the holes in the jigs youll be using.

Using the hollowing jigFirst, put an 8" dia. blade in your tablesaw. Any blade will do, but Ive found that an outer blade from an 8" stacked dado set leaves the smoothest surface.

Install the hollowing jig (Photo 2 and Fig. A, page 61). Align the front of the jig with the front edge of your saw, then tighten the knobs of the locking miter bars. Adjust the height of the saws blade so the top of the blade is just a bit below the surface of the table.

Place the blank in the jig. Press down lightly on the blank with one hand, turn on the saw and raise the blade 1/16" (on my saw, thats about 1/4 turn of the blade-elevation hand-wheel). Rotate the blank, clockwise, one complete revolution (Photo 3). (You might want to make a mark on the blank, so you can tell when youve turned the blank full circle.)

Keeping one hand on the blank, crank up the blade another 1/16" and repeat the procedure. Keep raising the

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1 2Saw the bowl blank as round as possible. I use a circle-cutting jig, where the blank rotates on a pin like a record on a turntable. The result is a near-perfect circle.

Install a jig on your tablesaw for hollowing the interior of the bowl. Tighten two knobs to lock the jig in the miter slot, so it cant move. Raise the blade so its even with the top of the saw table.

Place the blank in the jig and raise the blade 1/16". Rotate the blank one revolution. The result will be a dish-shaped, concave cut. Raise the blade another 1/16" and repeat the procedure.

Remove the blank after a few passes and check your progress. Keep raising the blade 1/16" at a time until the cut measures 6-1/2" across.

7-5/8" dia. blank

7-3/4" dia. hole

Circle-cutting jig

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blade until the cut measures 6-1/2" across (Photo 4 and Fig. B).

Repeat the same process on the opposite side of the bowl. Stop when the cut measures 2-1/2" across. Th is puts a fi nished look on the bottom of the bowl.

Using the coping jigFor this jig, put a 10" blade in your saw. Again, any blade will do. A rip blade will make the smoothest surface because its teeth have fl at tops. Adjust the blades height so the top of the blade is just below the tables surface.

Install the coping jig (Fig. C, p. 62). Be sure to hook it up to a vacwithout suction, sawdust will clog up the jig. Align the jig with the front edge of your saw and tighten the knobs of the locking miter bars. Turn on the saw and raise the blade until it cuts all the way through the jig, then lower the blade so the top of the blade sits just below the bases platform (C).

Place the bowl in the jig. Press down on the bowl, lightly, with one hand. Turn on the saw and raise the blade 1/16". Sound familiar? Rotate the bowl one complete revo-lution (Photo 5). Keeping one hand on the bowl, raise the

blade another 1/16" and rotate the bowl again. Repeat the procedure until the bowls rim is 1/2" thick (Photo 6). Aft er the last cut, leave the blade at that exact height.

To saw the decorative kerfs around the bowl, remove the bowl and draw 36 equally-spaced lines around its rim. (Th e lines will be about 5/8" apart; step them off with a compass.) Draw an index mark on the jig, then position the bowl so one line is opposite the mark. Raise the blade 1/8", lower it to the same position from where you started, rotate the bowl to the next line and make another cut (Photo 7 ).

Refi ne the bowls rim with a rabbet (Photo 8). Put a rabbeting bit in your router table and adjust its height to cut even with the bottom of the saw kerfs. You wont be able to use the bits bearing as a guide; instead, ride the bowl on the two inside edges of the fence. Adjust the space between the fences to make a cut thats 1/8" deep.

S O U R C ERockler, rockler.com, 800-279-4441, 8" x 8" x 3" Turning Blanks, avail-able in many species; Miter Slot Hardware Kit, #26993, $7.39 ea.; AccuRight Circle Jig for Bandsaws, #33981, $69.95.

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5 6Switch to a second jig to shape the outside of the bowl. Like the previous jig, this one is fixed in place with bars that lock in the miter slots. Rotate the blank to cut the wood.

Heres what the outside of the bowl will look like as you cut it. Raise the blade 1/16" at a time until the rim is 1/2" thick.

Saw decorative kerfs. Here, you hold the bowl stationary and raise and lower the blade 1/8" to make each kerf. Equally-spaced lines on the rim show you where to position the bowl for each cut.

Rout the bowls rim with a rabbeting bit. Rotate the bowl counterclockwise, against the rotation of the bit.

Rim

Index mark

Saw kerf

Spacing lines

Start of new cut

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Fig. B Cross Section of the Bowl in the Hollowing Jig

CENTER OF BLADE

FLUSH WITH THEFRONT EDGE OF

THE SAW

CENTER OF BLADES KERF

CENTER OF MITER SLOT

MITER SLOT LOCKING BAR

A

7-3/4" DIA. HOLE

HOLLOWINGJIG

BOWLBLANK

8" BLADE

2-1/2"

6-1/2"

7-5/8"

Fig. A Hollowing Jig

Making the Hollowing JigCut the base (A) from a flat piece of plywood or MDF. Draw a line down the middle of the base (Fig. A). Measure the distance from the center of your saw blade to the center of the right-hand miter slot. Draw a second line down the base. Measure the distance from the front edge of the saws table to the center of the saws arbor. Draw this line across the base.

Draw a 7-3/4" dia. circle from the intersection of the saw blade lines. Carefully cut out this circle with a jigsaw, then drill holes for the miter slot locking bars (see Source, page 60) and install the hardware. Youre good to go.

Part Name Qty. Th x W x LA Base 1 1 3/4" x 16" x 27"

Cutting List for Hollowing Jig

A tablesaw bowl? Watch the video at AmericanWoodworker.com/WebExtras



10" BLADE

1/2" THICK RIM

DUST

PORT

Part Name Qty. Th x W x LB Base 2 1 3/4" x 18" x 27"C Platform 1 3/4" x 12" x 11-1/2" (a)D Guide 5 3/4" x 12" x 11-1/2" (b)E Support 4 3/4" x 6" x 6"F Dustport 1 1/4" x 4" x 6"

Cutting List for Coping Jig

Notes: a) Miter one end. b) Miter the ends of all pieces, then crosscut to length as shown in Fig. D.

B

C D

E

F

CENTERLINEOF HOLE

CENTER OFSAW KERF

CENTER OF SAW BLADE

MITER SLOT LOCKING BARCENTER OF

MITER SLOT

2 x 3 DUST COLLECTION

OPENING

DUSTPORT

POCKETSCREW

5"

1-1/4" #8 F.H.SCREW (TYP.)

BLUNTCORNERS

8"

6"

12"

45 MITER7-3/4" DIA.

11-1/2"

Fig. C Coping Jig

Fig. E Cross Section of the Bowl in the Coping Jig

Fig. D Top and Side Views of Coping Jig

Making the Coping JigStart with the base (B). Draw the same three lines as you did for the coping jig. In addition, draw one line 5" in front of the center of saw blade line (Fig. C).

To make the platform (C) and guide pieces (D), start by sawing six pieces 12" wide by 11-1/2" long. Saw a 45 bevel on one end of each piece (Fig. D). Set aside one of these pieces for the platform. Stack the rest, so the bevels line up, and crosscut each piece individually, so the square ends also line up. Glue the stack together. Mark the center of the hole that will hold the bowl blank. Saw the hole on the bandsaw, either freehand or using a circle-cutting jig. Saw off the sharp corners of the hole. Finally, cut out a 2" wide by 3" long slot in the end of the platform for dust extraction, then glue the stack to the platform. Glue and screw the platform and stack to the base.

Make the supports (E) and fasten them to the base. Make the dustport (F) and screw it to the supports.


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Table Saw Bowl

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